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Sample records for radiative kaon decays

  1. RARE KAON DECAYS.

    Energy Technology Data Exchange (ETDEWEB)

    LITTENBERG, L.

    2005-07-19

    Lepton flavor violation (LFV) experiments have probed sensitivities corresponding to mass scales of well over 100 TeV, making life difficult for models predicting accessible LFV in kaon decay and discouraging new dedicated experiments of this type.

  2. Observation of the radiative kaon decay K- --> mu-pi0gammanu

    CERN Document Server

    Chikilev, O G; Britvich, G I; Datsko, K V; Filin, A; Inyakin, A V; Khmelnikov, V A; Konstantinov, S; Korolkov, I Ya; Leontiev, V M; Novikov, V; Obraztsov, V F; Polyakov, V; Romanovsky, V I; Shelikhov, V; Uvarov, V; Yushchenko, O P; Bolotov, V; Laptev, S; Duk, V; Polyarush, A Yu

    2005-01-01

    Using data collected with the ISTRA+ spectrometer during the 2001 run of the U-70 proton synchrotron in Protvino, we report the first observation of the radiative kaon decay K- -->mu-pi0gammanu. We find Br(Kmu3g)/Br(Kmu3) for two regions 5

  3. Overview of kaon decay physics

    CERN Document Server

    Peccei, Roberto D

    1995-01-01

    After a brief history of the insights gained from Kaon physics, the potential of Kaon decays for probing lepton number violation is discussed. Present tests of CTP and of Quantum Mechanics in the neutral Kaon sector are then reviewed and the potential of the Frascati \\Phi factory for doing incisive tests in this area is emphasized. The rest of this overview focuses on CP violating effects in the Kaon system. Although present observations of CP violation are perfectly consistent with the CKM model, we emphasize the theoretical and experimental difficulties which must be faced to establish this conclusively. In so doing, theoretical predictions and experimental prospects for detecting \\Delta S=1 CP violation through measurements of \\epsilon^\\prime/\\epsilon and of rare K decays are reviewed. The importance of looking for evidence for non-CKM CP-violating phases, through a search for a non-vanishing transverse muon polarization in K_{\\mu 3} decays, is also stressed.

  4. CP violation in kaon decays

    CERN Document Server

    D'Ambrosio, G

    1996-01-01

    We review the Standard Model predictions of CP violation in kaon decays. We present an elementary introduction to Chiral Perturbation Theory, four--quark effective hamiltonians and the relation among them. Particular attention is devoted to $K\\to 3\\pi$, $K\\to 2\\pi \\gamma$ and $K\\to \\pi \\bar{f} f$ decays.

  5. Observation of the destructive interference in the radiative kaon decay K- --> mu-nugamma

    CERN Document Server

    Tchikilev, O; Britvich, G; Filin, A; Konstantinov, A; Korolkov, I; Leontiev, V; Obraztsov, V; Polyakov, V; Romanonovsky, V; Semenov, V; Uvarov, V; Yushchenko, O; Bolotov, V; Duk, V; Makarov, A; Khudiakov, A; Polyarush, V Novikov A

    2010-01-01

    Using data collected with the ISTRA+ spectrometer at U70 proton synchrotron of IHEP, we report the first measurement of the destructive interference in the radiative kaon cecay K- -->mu-nugamma. We find the difference of the vector and axial form factors Fv-Fa=0.126+/-0.027+/-0.043. The measured value is two standard deviations above the O(p**4) ChPT prediction equal to 0.055. Inclusion of exotic tensor interaction gives Fv-Fa=0.144+/-0.044+/-0.035 and Ft=-0.0079+/-0.0113+/-0.0073, i.e. -0.03

  6. Kaons in flavour tagged B decays

    Science.gov (United States)

    Albrecht, H.; Ehrlichmann, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Nau, A.; Nowak, S.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Hast, C.; Kolanoski, H.; Kosche, A.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Wegener, D.; Bittner, M.; Eckstein, P.; Paulini, M. G.; Reim, K.; Wegener, H.; Mundt, R.; Oest, T.; Reiner, R.; Schmidt-Parzefall, W.; Funk, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hofmann, W.; Hüpper, A.; Khan, S.; Knöpfle, K. T.; Seeger, M.; Spengler, J.; Britton, D. I.; Charlesworth, C. E. K.; Edwards, K. W.; Hyatt, E. R. F.; Kapitza, H.; Krieger, P.; Macfarlane, D. B.; Patel, P. M.; Prentice, J. D.; Saull, P. R. B.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Reßing, D.; Schmidtler, M.; Schneider, M.; Schubert, K. R.; Strahl, K.; Waldi, R.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Cronström, H. I.; Jönsson, L.; Balagura, V.; Belyaev, I.; Chechelnitsky, S.; Danilov, M.; Droutskoy, A.; Gershtein, Yu.; Golutvin, A.; Kostina, G.; Litvintsev, D.; Lubimov, V.; Pakhlov, P.; Ratnikov, F.; Semenov, S.; Snizhko, A.; Soloshenko, V.; Tichomirov, I.; Zaitsev, Yu.

    1994-09-01

    Using the ARGUS detector at the e + e - storage ring DORIS II, flavour-dependent kaon production in B meson decays has been studied. Using the leptons as flavour tags, it has been possible to separately measure the multiplicities of K +, K - and K {/s 0} in inclusive B decays and in semileptonic B decays. The kaon production in semileptonic B decays was further used to estimate the ratio of charmed decays over all decays, and thus also the fraction of charmless B decays.

  7. One-prong $\\tau$ decays with kaons

    CERN Document Server

    Barate, R.; Ghez, Philippe; Goy, C.; Lees, J.P.; Merle, E.; Minard, M.N.; Pietrzyk, B.; Alemany, R.; Casado, M.P.; Chmeissani, M.; Crespo, J.M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Grauges, E.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L.M.; Pacheco, A.; Park, I.C.; Riu, I.; Colaleo, A.; Creanza, D.; De Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Becker, U.; Boix, G.; Cattaneo, M.; Ciulli, V.; Dissertori, G.; Drevermann, H.; Forty, R.W.; Frank, M.; Halley, A.W.; Hansen, J.B.; Harvey, John; Janot, P.; Jost, B.; Lehraus, I.; Leroy, O.; Mato, P.; Minten, A.; Moutoussi, A.; Ranjard, F.; Rolandi, Gigi; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I.R.; Tournefier, E.; Wright, A.E.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.C.; Pallin, D.; Perret, P.; Podlyski, F.; Hansen, J.D.; Hansen, J.R.; Hansen, P.H.; Nilsson, B.S.; Rensch, B.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J.C.; Rouge, A.; Rumpf, M.; Swynghedauw, M.; Verderi, M.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Lynch, J.G.; Negus, P.; O'Shea, V.; Raine, C.; Teixeira-Dias, P.; Thompson, A.S.; Buchmuller, O.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E.E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.M.; Cameron, W.; Dornan, P.J.; Girone, M.; Goodsir, S.; Martin, E.B.; Marinelli, N.; Sedgbeer, J.K.; Spagnolo, P.; Thomson, Evelyn J.; Williams, M.D.; Ghete, V.M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Betteridge, A.P.; Bowdery, C.K.; Buck, P.G.; Colrain, P.; Crawford, G.; Finch, A.J.; Foster, F.; Hughes, G.; Jones, R.W.L.; Robertson, N.A.; Williams, M.I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.G.; van Gemmeren, P.; Wachsmuth, H.; Zeitnitz, C.; Aubert, J.J.; Benchouk, C.; Bonissent, A.; Carr, J.; Coyle, P.; Etienne, F.; Motsch, F.; Payre, P.; Talby, M.; Thulasidas, M.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Buescher, Volker; Dietl, H.; Ganis, G.; Huttmann, K.; Lutjens, G.; Mannert, C.; Manner, W.; Moser, H.G.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Azzurri, P.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.F.; Heusse, P.; Hocker, Andreas; Jacholkowska, A.; Kim, D.W.; Le Diberder, F.; Lefrancois, J.; Lutz, A.M.; Schune, M.H.; Veillet, J.J.; Videau, I.; Zerwas, D.; Bagliesi, Giuseppe; Bettarini, S.; Boccali, T.; Bozzi, C.; Calderini, G.; Dell'Orso, R.; Ferrante, I.; Foa, L.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P.S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciaba, A.; Sguazzoni, G.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P.G.; Blair, G.A.; Cowan, G.; Green, M.G.; Medcalf, T.; Strong, J.A.; von Wimmersperg-Toeller, J.H.; Botterill, D.R.; Clifft, R.W.; Edgecock, T.R.; Norton, P.R.; Thompson, J.C.; Bloch-Devaux, Brigitte; Colas, P.; Emery, S.; Kozanecki, W.; Lancon, E.; Lemaire, M.C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.F.; Roussarie, A.; Schuller, J.P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S.N.; Dann, J.H.; Johnson, R.P.; Kim, H.Y.; Konstantinidis, N.; Litke, A.M.; McNeil, M.A.; Taylor, G.; Booth, C.N.; Cartwright, S.; Combley, F.; Kelly, M.S.; Lehto, M.; Thompson, L.F.; Affholderbach, K.; Boehrer, Armin; Brandt, S.; Grupen, C.; Prange, G.; Giannini, G.; Gobbo, B.; Rothberg, J.; Wasserbaech, S.; Armstrong, S.R.; Charles, E.; Elmer, P.; Ferguson, D.P.S.; Gao, Y.; Gonzalez, S.; Greening, T.C.; Hayes, O.J.; Hu, H.; Jin, S.; McNamara, P.A., III; Nachtman, J.M.; Nielsen, J.; Orejudos, W.; Pan, Y.B.; Saadi, Y.; Scott, I.J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Zobernig, G.

    1999-01-01

    One-prong $\\tau$ decays into final states involving kaons are studied with about 161k $\\tau^+\\tau^-$ events collected by the ALEPH detector from 1991 to 1995. Charged kaons are identified by dE/dx measurement, while $K^0_L$'s are detected through their interaction in calorimeters. Branching ratios are measured for the inclusive mode, $B(\\tau^-\\rightarrow K^-X\

  8. Rare kaon, muon, and pion decay

    Energy Technology Data Exchange (ETDEWEB)

    Littenberg, L.

    1998-12-01

    The author discusses the status of and prospects for the study of rare decays of kaons, muons, and pions. Studies of rare kaon decays are entering an interesting new phase wherein they can deliver important short-distance information. It should be possible to construct an alternative unitarity triangle to that determined in the B sector, and thus perform a critical check of the Standard Model by comparing the two. Rare muon decays are beginning to constrain supersymmetric models in a significant way, and future experiments should reach sensitivities which this kind of model must show effects, or become far less appealing.

  9. CP Violation in Kaon Decays (II)

    CERN Document Server

    Yamanaka, Taku

    2014-01-01

    Major progress has been made in kaon physics in the past 50 years. The number of KL->pi+pi- events has increased by 6 orders of magnitude, and the observed CP violation was experimentally proven to be caused by a complex phase in the CKM matrix. Recent kaon experiments are now searching for new physics beyond the standard model with the K->pi nu nu-bar decays. The branching ratio of K->pi nu nu-bar decays are 7-8 orders of magnitude smaller than the branching ratio of KL->pi+ pi-. This paper reviews the progress of kaon experiments in the US and Japan, and how the 6-7 orders of magnitude improvements were possible in the past 50 years.

  10. Direct CP violation in neutral kaon decays

    Indian Academy of Sciences (India)

    Wojciech Wiślicki

    2004-03-01

    The final result of the NA48 experiment is presented and performed at the CERN SPS neutral kaon beams, on the direct CP violation parameter Re$('/)$, as measured from the decay rates of neutral kaons into two pions. The data collected in the years 1997-2001 yield the evidence for the direct CP violation with Re$('/)=(14.7± 2.2)× 10^{-4}$. Description of experimental method and systematics, comparison with the corresponding FNAL result and discussion of some implications for the theory are given.

  11. Non-perturbative renormalization in kaon decays

    CERN Document Server

    Donini, Andrea; Martinelli, G; Rossi, G C; Talevi, M; Testa, M; Vladikas, A

    1996-01-01

    We discuss the application of the MPSTV non-perturbative method \\cite{NPM} to the operators relevant to kaon decays. This enables us to reappraise the long-standing question of the $\\Delta I=1/2$ rule, which involves power-divergent subtractions that cannot be evaluated in perturbation theory. We also study the mixing with dimension-six operators and discuss its implications to the chiral behaviour of the $B_K$ parameter.

  12. $\\tau$ decays with neutral kaons

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Anderson, K.J.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Bailey, I.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Boeriu, O.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couchman, J.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; Davis, R.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Feld, L.; Ferrari, P.; Fiedler, F.; Fierro, M.; Fleck, I.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lawson, I.; Layter, J.G.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; Lillich, J.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Merritt, F.S.; Mes, H.; Meyer, I.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Przybycien, M.; Quadt, A.; Rembser, C.; Rick, H.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trefzger, T.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

    2000-01-01

    The branching ratio of the tau lepton to a neutral K meson is measured from a sample of approximately 200,000 tau decays recorded by the OPAL detector at centre-of-mass energies near the Z0 resonance. The measurement is based on two samples which identify one-prong tau decays with KL and KS mesons. The combined branching ratios are measured to be B(tau- -->pi- K0bar nutau) = (9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) = (3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) = (3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second systematic.

  13. New Physics Signatures in Kaon Decays

    CERN Document Server

    Blanke, Monika

    2013-01-01

    Kaon physics provides a unique opportunity to identify new flavour and CP violating interactions beyond the Standard Model (SM). In the SM, implied by the hierarchical structure of the CKM matrix and the GIM mechanism, flavour changing neutral current processes are most strongly suppressed in the kaon sector while the suppression is much less effective in the B meson systems. Thus their theoretical cleanness makes rare K decays, in particular the K -> pi nu anti-nu system, extremely well suited to look for deviations from their tiny SM values. Despite the increasingly stringent constraints on new physics from direct search experiments as well as indirect searches in B meson decays, large enhancements of both K^+ -> pi^+ nu anti-nu and K_L -> pi^0 nu anti-nu are still possible, and deviations from the SM could be observed even for a multi-TeV new physics scale. In addition the correlation betweeen the charged and neutral K -> pi nu anti-nu modes provides insight on the new physics operator structure in K^0 - a...

  14. Searches for very rare decays of kaons

    Energy Technology Data Exchange (ETDEWEB)

    Lang, K. [Univ. of Texas, Austin, TX (United States)

    1997-01-01

    The physics motivation for searches for very rare kaon decays, either forbidden or suppressed within the Standard Model, is briefly discussed. Simple arguments conclude that such searches probe possible new forces at a 200 TeV mass scale or constitute a precision test of the electroweak model. The examples of such process are decays of K{sub L}{sup 0} {yields} {mu} {sup {+-}}e{sup -+}, K{sup +} {yields} {pi}{sup +} {mu}{sup +} e{sup -}, K{sub L}{sup 0} {yields} {mu}{sup +} {mu}{sup -}, and K{sup +} {yields} {pi} {yields} {pi}{sup +}{nu}{bar {nu}}. We present the current experimental status and describe the new efforts to reach sensitivities down to one part in 10{sup 12}. The discussion is focused on the experimental program at the Alternating Gradient Synchrotron at Brookhaven National Laboratory, where intense beams make such studies possible.

  15. Cosmology tests in rare kaon decays

    Directory of Open Access Journals (Sweden)

    Duk Viacheslav

    2016-01-01

    Full Text Available The Standard Model (SM of particle physics is an extremely successful theory that effectively describes strong and electroweak interactions up to the energies presently accessible. Still, the SM does not explain the observed parameters of neutrino oscillations, baryon asymmetry of the Universe and Dark Matter (DM, and contains a fine-tuning of 16 orders of magnitude (the gauge hierarchy problem. Various New Physics (NP models beyond the SM have been developed in order to address the above limitations. This paper concentrates on several models related to cosmology and their tests in rare kaon decays. In particular, recent NA48/2 results on the search for heavy neutrinos, light in-flatons and dark photons are presented. Prospects for the ongoing NA62 experiment are discussed.

  16. Rare and forbidden kaon decays at the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Kettell, S.

    1997-12-09

    An overview of the Rare Kaon Decay program at the AGS is presented, with particular emphasis on the three major experiments currently running and analyzing data. A brief overview of earlier kaon decay experiments and of the AGs performance improvements is also provided. This review concludes with a discussion of proposed and developing experiments planned to run in the year 2000 and beyond (AGS-2000).

  17. NA48 results on neutral kaon and hyperon rare decays

    Indian Academy of Sciences (India)

    Nicolò Cartiglia

    2004-03-01

    The NA48 Collaboration has performed an extensive program of kaon and hyperon rare decays using the data collected during the period 1997-2001. This program includes new tests of chiral perturbation theory, new measurements of the mass and $K_{S}$ lifetime and the possibility to measure the Cabibbo angle using $\\Xi$ beta decays.

  18. Charged kaon and proton production in B-hadron decays

    Science.gov (United States)

    Tegenfeldt, Fredrik Per

    The production of charged kaons and protons in B-hadron decays has been measured in e+e- annihilations at centre-of-mass energies corresponding to the Z0 mass. In total 1.6 million hadronic Z0 decays were analysed, corresponding to about 690000 B-hadron decays. They were collected using the DELPHI detector at the LEP collider at CERN during 1994 and 1995. Events containing B-hadron decays were identified using special characteristics of the B-hadron decay topology. In particular, the long lifetime of the B-hadron leads to decay vertices significantly displaced relative the interaction point. These so called secondary vertices were reconstructed using a powerful micro vertex detector. In order to discriminate B-hadron decay products from fragmentation tracks, a method was used where the impact parameter measured by the vertex detector was employed as a discriminating variable. The tracks were thus divided into two classes, one compatible with the interaction point and the other compatible with a secondary vertex. An unfolding method was used to extract the true B-hadron decay tracks from the two classes. Charged kaons and protons were identified using the Ring Imaging CHerenkov (RICH) detector and corrected for misidentification using an efficiency matrix. The analysis resulted in charged kaon and proton spectra from B-hadron decays, including previously unmeasured momentum regions. Integrating the spectra yielded the following multiplicities n(B- hadron-->K+/- X)=0.683+/-0.021(stat) +/-0.017(syst) n(B- hadron-->p/p X)=0.127+/-0.013(stat) +/-0.019(syst) where the proton multiplicity does not include Λ baryon decay products.

  19. Classical Illustrations of CP Violation in Kaon Decays

    CERN Document Server

    Rosner, Jonathan L; Rosner, Jonathan L.; Slezak, Scott A.

    2001-01-01

    It is easy to construct classical 2-state systems illustrating the behavior of the short-lived and long-lived neutral $K$ mesons in the limit of CP conservation. The emulation of CP violation is more tricky, but is provided by the two-dimensional motion of a Foucault pendulum. Analogies are drawn between the pendulum and observables in neutral kaon decays. An emulation of CP- and CPT-violation using electric circuits is also discussed.

  20. Three-prong $\\tau$ decays with charged kaons

    CERN Document Server

    Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Becker, U; Bazarko, A O; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Hansen, J B; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rizzo, G; Rolandi, Luigi; Rousseau, D; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Buchmüller, O L; Dhamotharan, S; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Moutoussi, A; Nash, J; Sedgbeer, J K; Spagnolo, P; Stacey, A M; Williams, M D; Ghete, V M; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Carr, J; Coyle, P; Diaconu, C A; Etienne, F; Konstantinidis, N P; Leroy, O; Motsch, F; Payre, P; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Antonelli, M; Ragusa, F; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Schune, M H; Simion, S; Tournefier, E; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zobernig, G

    1998-01-01

    Final states with charged kaons in three-prong $\\tau$ decays are studied by exploiting the particle identification from the dE/dx measurement. The results are based on a sample of about $1.6\\times 10^{5}$ detected $\\tau$ pairs collected with the ALEPH detector between 1991 and 1995 around the Z peak. The following branching ratios have been measured: $B(\\tau^{-}~\\rightarrow~K^{-}K^{+}\\pi^{-}\

  1. Rare Kaon Decays on the Lattice

    CERN Document Server

    Isidori, Gino; Turchetti, P; Isidori, Gino; Martinelli, Guido; Turchetti, Paolo

    2006-01-01

    We show that long distance contributions to the rare decays K -> pi nu nu-bar and K -> pi l+ l- can be computed using lattice QCD. The proposed approach requires well established methods, successfully applied in the calculations of electromagnetic and semileptonic form factors. The extra power divergences, related to the use of weak four-fermion operators, can be eliminated using only the symmetries of the lattice action without ambiguities or complicated non-perturbative subtractions. We demonstrate that this is true even when a lattice action with explicit chiral symmetry breaking is employed. Our study opens the possibility of reducing the present uncertainty in the theoretical predictions for these decays.

  2. Rare kaon decays on the lattice

    Energy Technology Data Exchange (ETDEWEB)

    Isidori, Gino [INFN, Laboratori Nazionali di Frascati, I-00044 Frascati (Italy)]. E-mail: gino.isidori@lnf.infn.it; Martinelli, Guido [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, P.le A. Moro 2, I-00185 Rome (Italy); Turchetti, Paolo [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, P.le A. Moro 2, I-00185 Rome (Italy)

    2006-02-02

    We show that long-distance contributions to the rare decays K->{pi}{nu}{nu}-bar and K->{pi}-bar {sup +}-bar {sup -} can be computed using lattice QCD. The proposed approach requires well established methods, successfully applied in the calculations of electromagnetic and semileptonic form factors. The extra power divergences, related to the use of weak four-fermion operators, can be eliminated using only the symmetries of the lattice action without ambiguities or complicated non-perturbative subtractions. We demonstrate that this is true even when a lattice action with explicit chiral symmetry breaking is employed. Our study opens the possibility of reducing the present uncertainty in the theoretical predictions for these decays.

  3. Non-leptonic kaon decays at large $N_c$

    CERN Document Server

    Donini, A; Pena, C; Romero-López, F

    2016-01-01

    We study the scaling with the number of colours, $N_c$, of the weak amplitudes mediating kaon mixing and decay. We evaluate the amplitudes of the two relevant current-current operators on the lattice for $N_c=3-7$. We conclude that the subleading $1/N_c$ corrections in $\\hat{B}_K$ are small, but those in the $K \\rightarrow \\pi\\pi$ amplitudes are large and fully anti-correlated in the $I=0, 2$ isospin channels. We briefly comment on the implications for the $\\Delta I=1/2$ rule.

  4. Kaon-nucleon couplings for weak decays of hypernuclei

    CERN Document Server

    Savage, M J

    1995-01-01

    We investigate the weak kaon-nucleon (NNK) S-wave and P-wave interactions using heavy baryon chiral perturbation theory. The leading 1-loop SU(3) breaking contributions to the ppK, pnK, and nnK couplings are computed. We find that they suppress all NNK amplitudes by 30\\% to 50\\%. The ratio of neutron-induced to proton-induced hypernuclear decay widths is sensitive to such reductions. It has been argued that the discrepancy between the predicted and observed P-wave amplitudes in \\Delta s=1 hyperon decay results from an accidental cancellation between tree-level amplitudes, and is not a fundamental problem for chiral perturbation theory. Agreement between experimentally determined NNK P-wave amplitudes and our estimates would support this explanation.

  5. One-prong τ decays with neutral kaons

    Science.gov (United States)

    Acciarri, M.; Adam, A.; Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alpat, B.; Alcaraz, J.; Allaby, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Andreev, V. P.; Angelescu, T.; Antreasyan, D.; Arefiev, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Baksay, L.; Ball, R. C.; Banerjee, S.; Banicz, K.; Barillère, R.; Barone, L.; Bartalini, P.; Baschirotto, A.; Basile, M.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Boucham, A.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brigljevic, V.; Brock, I. C.; Bujak, A.; Burger, J. D.; Burger, W. J.; Burgos, C.; Busenitz, J.; Buytenhuijs, A.; Cai, X. D.; Capell, M.; Romeo, G. Cara; Caria, M.; Carlino, G.; Cartacci, A. M.; Casaus, J.; Castellini, G.; Castello, R.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chan, A.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Commichau, V.; Costantini, S.; Cotorobai, F.; de La Cruz, B.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; de Boeck, H.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; Denotaristefani, F.; Dibitonto, D.; Diemoz, M.; Dionisi, C.; Dittmar, M.; Dominguez, A.; Doria, A.; Dorne, I.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duinker, P.; Duran, I.; Dutta, S.; Easo, S.; Efremenko, Yu.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Ernenwein, J. P.; Extermann, P.; Fabbretti, R.; Fabre, M.; Faccini, R.; Falciano, S.; Favara, A.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Gailloud, M.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gau, S. S.; Gentile, S.; Gerald, J.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; Goldstein, J.; Gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M. W.; Gu, C.; Guanziroli, M.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hartmann, B.; Hasan, A.; He, J. T.; Hebbeker, T.; Hervé, A.; Hilgers, K.; van Hoek, W. C.; Hofer, H.; Hoorani, H.; Hou, S. R.; Hu, G.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jin, B. N.; Jones, L. W.; de Jong, P.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, D.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirkby, J.; Kirsch, S.; Kittel, W.; Klimentov, A.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krenz, W.; Kuijten, H.; Kunin, A.; de Guevara, P. Ladron; Landi, G.; Lapoint, C.; Lassila-Perini, K.; Laurikainen, P.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, J.; Lecoq, P.; Le Coultre, P.; Lee, J. S.; Lee, K. Y.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Levtchenko, P.; Li, C.; Lieb, E.; Lin, W. T.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Liu, Z. A.; Lohmann, W.; Longo, E.; Lu, W.; Lu, Y. S.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, W. G.; Macchiolo, A.; Maity, M.; Malgeri, L.; Malik, R.; Malinin, A.; Maña, C.; Mangla, S.; Maolinbay, M.; Marchesini, P.; Marin, A.; Martin, J. P.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McNally, D.; Mele, S.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; van Mil, A. J. W.; Mir, Y.; Mirabelli, G.; Mnich, J.; Möller, M.; Monaco, V.; Monteleoni, B.; Moore, R.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nagy, E.; Nahn, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Ostonen, R.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Pevsner, A.; Piccolo, D.; Pieri, M.; Pinto, J. C.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Produit, N.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Redaelli, M.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Robohm, A.; Rodin, J.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Röhner, S.; Romero, L.; Rosier-Lees, S.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubio, J. A.; Rykaczewski, H.; Salicio, J.; Salicio, J. M.; Sanchez, E.; Santocchia, A.; Sarakinos, M. E.; Sarkar, S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schäfer, C.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Schoeneich, B.; Scholz, N.; Schopper, H.; Schotanus, D. J.; Schulte, R.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shukla, J.; Shumilov, E.; Son, D.; Sopczak, A.; Soulimov, V.; Smith, B.; Spickermann, T.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Stoyanov, B.; Strauch, K.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Timellini, R.; Ting, Samuel C. C.; Ting, S. M.; Toker, O.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Tuchscherer, H.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Voelkert, R.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vorobyov, An. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, J. C.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Weber, A.; Weill, R.; Willmott, C.; Wittgenstein, F.; Wu, S. X.; Wynhoff, S.; Xu, J.; Xu, Z. Z.; Yang, B. Z.; Yang, C. G.; Yang, G.; Yao, X. Y.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zalite, An.; Zemp, P.; Zeng, J. Y.; Zeng, M.; Zeng, Y.; Zhang, Z.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhou, Y.; Zhu, G. Y.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.

    1995-02-01

    We have analyzed one-prong τ decays with neutral kaons using the information from a fine-grained hadron calorimeter. The data sample consists of 43 500 Z → τ+τ-( γ) events collected by the L3 detector at LEP in 1991, 1992 and 1993. The following branching fractions are measured: B(τ - → ν τπ -overlineK0) = 0.0095 ± 0.0015 (stat) ± 0.0006(syst); B(τ - → ν τπ - π 0overlineK0) = 0.0041 ± 0.0012(stat) ± 0.0003(syst) and B(τ - → ν τπ -K 0overlineK0) = 0.0031 ± 0.0012(stat) ± 0.0004(syst) .

  6. Radiative Ke3 decays revisited

    CERN Document Server

    Gasser, J; Paver, N; Verbeni, M

    2004-01-01

    Motivated by recent experimental results and ongoing measurements, we review the chiral perturbation theory prediction for radiative Ke3 decays (neutral kaons). Special emphasis is given on the stability of the inner bremsstrahlung-dominated relative branching ratio vs. the Ke3 form factors, and on the separation of the structure dependent amplitude in differential distributions over the phase space. For the structure dependent terms, an assessment of the order p^6 corrections is given. In particular, a full next-to-leading order calculation of the axial component is performed. The experimental analysis of the photon energy spectrum is discussed, and other potentially useful distributions are introduced.

  7. Semileptonic Kaon Decay in Staggered Chiral Perturbation Theory

    CERN Document Server

    Bernard, C; Gámiz, E

    2013-01-01

    The determination of $\\vert V_{us}\\vert$ from kaon semileptonic decays requires the value of the form factor $f_+(q^2=0)$, which can be calculated precisely on the lattice. We provide the one-loop partially quenched staggered chiral perturbation theory expressions that may be employed to analyze staggered simulations of $f_+(q^2)$ with three light flavors. We consider both the case of a mixed action, where the valence and sea sectors have different staggered actions, and the standard case where these actions are the same. The momentum transfer $q^2$ of the form factor is allowed to have an arbitrary value. We give results for the generic situation where the $u$, $d$, and $s$ quark masses are all different, $N_f=1+1+1$, and for the isospin limit, $N_f=2+1$. The expression we obtain for $f_+(q^2)$ is independent of the mass of the (valence) spectator quark. In the limit of vanishing lattice spacing, our results reduce to the one-loop continuum partially quenched expression for $f_+(q^2)$, which has not previous...

  8. Aspects of radiative K^+_e3 decays

    CERN Document Server

    Kubis, B; Müller, E H; Schmid, M; Kubis, Bastian; Müller, Eike H; Schmid, Martin

    2006-01-01

    We re-investigate the radiative charged kaon decay K+- --> pi0 e+- nu_e gamma in chiral perturbation theory, merging the chiral expansion with Low's theorem. We thoroughly analyze the precision of the predicted branching ratio relative to the non-radiative decay channel. Structure dependent terms and their impact on differential decay distributions are investigated in detail, and the possibility to see effects of the chiral anomaly in this decay channel is emphasized.

  9. Study of charged kaon production in three-prong tau decays

    Energy Technology Data Exchange (ETDEWEB)

    Hao Wei

    1996-02-01

    This thesis presents the measurement of kaon production in 3-prong {tau} decays. The data sample of Z{sup 0} events is used that was recorded with the DELPHI detector at LEP in 1992, 1993 and 1994. Charged kaons in the {tau} decay are identified on a track-by-track basis using the Ring Imaging Cherenkov detector (RICH). The branching ratios of {tau}{sup -}{yields}K{sup -}K{sup +}{pi}{sup -} (neutrals) {nu}{sub {tau}} and {tau}{sup -}{yields}K{sup -}{pi}{sup +}{pi}{sup -} (neutrals) {nu}{sub {tau}} are determined. The resonance structure of these two decays is studied. Evidence for a simple QCD process of kaon pair production in {tau} decay is discussed. (orig.).

  10. NA48/2. Precision Measurement of Charged Kaon Decay parameters with an Extended NA48 Setup

    CERN Multimedia

    De beer, M; Derre, J; Celeghini, E; Bazylev, S; Falaleev, V; Peyaud, B; Bendel, M; Kekelidze, V; Potrebenikov, Y; Ceccucci, A; Behler, M; Madigozhin, D

    2002-01-01

    A high statistics study of charged kaon decays is proposed using a novel design for simultaneous $K^+/K^-$ beams, and NA48 setup upgraded with a transition radiation detector. The main goal is to measure CP-violating asymmetry in $K^{\\pm}\\rightarrow \\pi^+ \\pi^- \\pi^{\\pm}$ decays with an accuracy of $2.2 \\times 10^{-4}$. In addition CP-violating asymmetry will be measured in $K^{\\pm}\\rightarrow \\pi^0 \\pi^0 \\pi^{\\pm}$ decays, more than $10^6$ of $K_{e4}$ decays will be accumulated which allow to measure a scattering length parameter $a^0_0$ with an accuracy better than 0.01, and some other rare decays will be studied as well.

  11. Limits on Lorentz violation in neutral-Kaon decay

    NARCIS (Netherlands)

    Vos, K.K.; Wilschut, H. W.; Timmermans, R. G. E.

    2013-01-01

    The KLOE collaboration recently reported bounds on the directional dependence of the lifetime of the short-lived neutral kaon K_S with respect to the cosmic microwave background dipole anisotropy. We interpret their results in a general framework developed to probe Lorentz violation in the weak

  12. Exploration of Lorentz violation in neutral-kaon decay

    NARCIS (Netherlands)

    Vos, K.K.; Noordmans, J.P.; Wilschut, H. W.; Timmermans, R.G.E.

    2014-01-01

    The KLOE Collaboration recently reported bounds on the directional dependence of the lifetime of the short-lived neutral kaon K-S(0) with respect to the dipole anisotropy of the cosmic microwave background. We interpret their results in an effective field theory framework developed to probe the

  13. The measurement of CP asymmetries in the three-body charmless decay neutral B meson decays to neutral kaon(S) neutral kaon(S) neutral kaon(S)

    Science.gov (United States)

    Hadavand, Haleh K.

    In this dissertation, a measurement of CP-violating effects in decays of neutral B mesons is presented. The data sample for this measurement consists of about 272 million Upsilon(4 S) → BB¯ decays collected between 1999 and 2004 with the BABAR detector at the PEP-II asymmetric-energy e+e- collider, located at the Stanford Linear Accelerator Center. One neutral B meson is fully reconstructed in the CP eigenstate B0 → K0sK0s K0s . The other B meson is determined to be either a B0 or a B¯0, at the time of its decay, from the properties of its decay products. The proper time Deltat elapsed between the decay of the two mesons is determined by reconstructing their decay vertices, and by measuring the distance between them. A novel technique for determining the B vertex of the decay to the CP eigenstate B 0 → K0sK0s K0s has been applied since the tracks in the final state do not originate from the B decay vertex. The time-dependent CP asymmetry amplitudes are determined by the distributions of Delta t in events with a reconstructed B meson in the CP eigenstate. The detector resolution and the b flavor tagging parameters are constrained by the Deltat distributions of events with a fully reconstructed flavor eigenstate. Because of the special topology of this decay, the detector resolution on Delta t must be checked for consistency with decays with tracks which originate from the B decay. From a maximum likelihood fit to the Delta t distributions of all selected events, the value of the CP violating asymmetries are measured to be S3K0s=-0.71+0.38 -0.32 +/- 0.04 and C3K0s=-0.34+0.28 -0.25 +/- 0.05. Fixing C = 0 we measure the time-dependent CP asymmetry amplitude sin 2beta = -S3K0s=0.79+0.39 -0.36 +/- 0.04. The value of sin 2beta is in agreement with Standard Model predictions.

  14. Constrains on $L_\\mu-L_\\tau$ Gauge Interactions from Rare Kaon Decay

    CERN Document Server

    Ibe, Masahiro; Suzuki, Motoo

    2016-01-01

    The model with the $L_\\mu -L_\\tau$ gauge symmetry is the least constrained model as a resolution to the disagreement of the muon anomalous magnetic moment between the theoretical prediction and the experimental result. In this paper, we discuss how well the $L_\\mu - L_\\tau$ model can be constrained by looking for the decay of the charged kaon associated with the $L_\\mu-L_\\tau$ gauge boson. More concretely, we consider searches for single muon tracks from the decays of stopped charged kaons as performed in the E949 experiment. As a result, we find that favored parameter region for the muon anomalous magnetic moment can be tested by using $10$ times larger number of stopped charged kaons and about $100$ times better photon rejection rate than the E949 experiment.

  15. Kaon decay studies at CERN SPS in the last decades

    Science.gov (United States)

    Ceccucci, A.; Goudzovski, E.; Kekelidze, V.; Madigozhin, D.; Potrebenikov, I.

    2016-07-01

    This review summarizes the kaon experimental results obtained in the last 15 years on the basis of data collected on the SPS in CERN with a participance of JINR physicists. These results contribute essentially into the Standard Model checks and search for its extension, fundamental symmetry violations and low energy strong interactions theory development. A progress in the experimental technique and prospects for the future results are also discussed.

  16. Radiative widths of neutral kaon excitations

    Indian Academy of Sciences (India)

    Sunil V Somalwar; KTeV Collaboration

    2004-03-01

    We observe 147 events of the axial vector pair $K_{1} (1270) - K_{1} (1400)$ produced in the Coulomb field of a Pb target and measure the radiative widths $ (K_{1} (1400) → K^{0} + ) = 280.8 ± 23.2$ (stat.) $± (40.4)$ (syst.) keV and $ (K_{1} (1270) → K^{0} + ) = 73.2 ± 6.1$ (stat.) $± 28.3$ (syst.) keV. These first measurements are lower than the quark-model predictions. We also place upper limits on the radiative widths for $K^{*} (1410)$ and $K_{2}^{*} (1430)$ and find that the letter is very small in accord with $SU(3)$ invariance in the naive quark model.

  17. A transition radiation detector for kaon/pion separation

    Energy Technology Data Exchange (ETDEWEB)

    Baake, M.; Diekmann, B.; Gebert, F.; Heinloth, K.; Holzkamp, S.; Koersgen, G.; Voigtlaender-Tetzner, A. (Bonn Univ. (Germany, F.R.)); Bagdassarian, L.; Kazarian, C.; Oganessian, A. (Erevanskij Gosudarstvennyj Univ. (USSR))

    1989-09-01

    The experiment WA69 at the CERN Omega spectrometer facility has studied fixed target photon and hadron production of inclusive hadronic final states with tagged photon beams of 65-175 GeV in comparison to charged hadron beams ({pi} and K) of 80 and 140 GeV fixed energies. For the identification of final state pions and kaons above 100 GeV/c a transition radiation detector (TRAD) has been developed. This detector was constructed of 12 modules, each consisting of a polypropylene fibre radiator and a proportional chamber with a xenon/methane gas mixture to detect the transition radiation produced by fast moving charged particles. We give a description of the detector setup and working conditions. As a first result obtained with the TRAD the ratio of photoproduced kaons and pions in the extreme forward regime (x{sub F}>0.7 and -t<1 GeV{sup 2}) is measured to be 10.2(+-1.7)% which is in agreement with VDM predictions. (orig.).

  18. Measurements Of The Branching Fraction, Cp Asymmetry And Isospin Asymmetry Of The Radiative Penguin Decay Neutral B Meson Decays To Neutral Kaon(0) Resonance And A Search For The Decays B Meson Decays To Rho Photon And Neutral B Meson Decays To Omega Photon At Babar

    CERN Document Server

    Spradlin, P M

    2005-01-01

    Radiative penguin decays of B mesons provide a fertile ground for precision tests of the Standard Model. Because such decays must proceed through 1-loop or higher processes in Standard Model perturbation theory, they are quite rare and their amplitudes are particularly susceptible to interference from physics beyond the Standard Model. This thesis presents measurements carried out at the BABAR, experiment of the branching fraction B , CP asymmetry parameter ACP and isospin asymmetry parameter Δ0- of the radiative penguin decay B0 → K*0γ. The results of these measurements are BB0→K*0 g=3.92±0.20± 0.24×10-5 ACPB→K*g =-0.013±0.036±0.010 D0-B→K*g =0.050±0.045±0.037. The measurements are consistent with Standard Model predictions, but do not rule out future discovery of non- Standard Model deviations with an enlarged data set. This thesis also presents a related search for the r...

  19. W.K.H. Panofsky Prize in Experimental Particle Physics Talk: Kaons Redux- Seeking New Physics with Rare Decays of Kaons

    Science.gov (United States)

    Bryman, Douglas

    2011-04-01

    Studies of rare decays of kaons have been important in establishing the current picture of particle physics and in constraining hypothetical new approaches which go beyond the Standard Model to deal with its known deficiencies. Experimental capabilities have increased in concert with theoretical understanding making this approach to searching for new physics more viable than ever and essential, even in the era of the LHC. In this talk, I will discuss the most interesting and incisive rare kaon decay experiments, particularly K+ -->π+ ν ν andKL0 -->π0 ν ν , emphasizing the prospects for major advancements in the near term and at future high intensity proton accelerators.

  20. Kaon semileptonic decay form factors with HISQ valence quarks

    CERN Document Server

    Gamiz, E; Bazavov, A; Bernard, C; Bouchard, C; DeTar, C; Du, D; El-Khadra, A X; Foley, J; Freeland, E D; Gottlieb, Steven; Heller, U M; Kim, J; Kronfeld, A S; Laiho, J; Levkova, L; Mackenzie, P B; Neil, E T; Oktay, M B; Qiu, Si-Wei; Simone, J N; Sugar, R; Toussaint, D; Van de Water, R S; Zhou, R

    2012-01-01

    We report on the status of our kaon semileptonic form factor calculations using the highly-improved staggered quark (HISQ) formulation to simulate the valence fermions. We present results for the form factor f_+^{K \\pi}(0) on the asqtad N_f=2+1 MILC configurations, discuss the chiral-continuum extrapolation, and give a preliminary estimate of the total error. We also present a more preliminary set of results for the same form factor but with the sea quarks also simulated with the HISQ action; these results include data at the physical light quark masses. The improvements that we expect to achieve with the use of the HISQ configurations and simulations at the physical quark masses are briefly discussed.

  1. Vus and lepton universality from kaon decays with the KLOE detector

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bossi, F; Branchini, P; Caloi, R; Campana, P; Capon, G; Capussela, T; Ceradini, F; Cesario, F; Chi, S; Chiefari, G; Ciambrone, P; Crucianelli, F; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martemyanov, M; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Sibidanov, A; Spadaro, T; Testa, M; Tortora, L; Valente, P; Venanzoni, G; Versaci, R; Xu, G

    2008-01-01

    KLOE has measured most decay branching ratios of Ks, Kl and K+/- mesons. It has also measured the Kl and the K+- lifetime and determined the shape of the form factors involved in kaon semileptonic decays. We present in the following a description of the above measurements and a well organized compendium of all of our data, with particular attention to correlations. These data provide the basis for the determination of the CKM parameter Vus and a test of the unitarity of the quark flavor mixing matrix. We also test lepton universality and place bounds on new physics using measurements of Vus from Kl2 and Kl3 decays.

  2. Model independent measurement of the leptonic kaon decay $K^{\\pm}\\to \\mu^{\\pm}\

    CERN Document Server

    Marchevski, Radoslav; Baldini, W; Balev, S; Batley, J R; Behler, M; Bifani, S; Biino, C; Bizzeti, A; Bloch-Devaux, B; Bocquet, G; Cabibbo, N; Calvetti, M; Cartiglia, N; Ceccucci, A; Cenci, P; Cerri, C; Cheshkov, C; ChèZe, J B; Clemencic, M; Collazuol, G; Costantini, F; Cotta Ramusino, A; Coward, D; Cundy, D; Dabrowski, A; Dalpiaz, P; Damiani, C; De Beer, M; Derré, J; Dibon, H; Dilella, L; Doble, N; Eppard, K; Falaleev, V; Fantechi, R; Fidecaro, M; Fiorini, L; Fiorini, M; Fonseca Martin, T; Frabetti, P L; Gatignon, L; Gersabeck, E; Gianoli, A; Giudici, S; Gonidec, A; Goudzovski, E; Goy Lopez, S; Holder, M; Hristov, P; Iacopini, E; Imbergamo, E; Jeitler, M; Kalmus, G; Kekelidze, V; Kleinknecht, K; Kozhuharov, V; Kubischta, W; Lamanna, G; Lazzeroni, C; Lenti, M; Litov, L; Madigozhin, D; Maier, A; Mannelli, I; Marchetto, F; Marel, G; Markytan, M; Marouelli, P; Martini, M; Masetti, L; Mazzucato, E; Michetti, A; Mikulec, I; Molokanova, N; Monnier, E; Moosbrugger, U; Morales Morales, C; Munday, D J; Nappi, A; Neuhofer, G; Norton, A; Patel, M; Pepe, M; Peters, A; Petrucci, F; Petrucci, M C; Peyaud, B; Piccini, M; Pierazzini, G; Polenkevich, I; Potrebenikov, Yu; Raggi, M; Renk, B; Rubin, P; Ruggiero, G; Savrié, M; Scarpa, M; Shieh, M; Slater, M W; Sozzi, M; Stoynev, S; Swallow, E; Szleper, M; Valdata-Nappi, M; Vallage, B; Velasco, M; Veltri, M; Venditti, S; Wache, M; Wahl, H; Walker, A; Wanke, R; Widhalm, L; Winhart, A; Winston, R; Wood, M D; Wotton, S A; Zinchenko, A; Ziolkowski , M

    2016-01-01

    A measurement of the branching ratio of the rare leptonic kaon decay K ± → μ ± ν μ e + e − is pre- sented using data collected by the NA48/2 experiment in 2003 and 2004. The measurement is performed in the region M ee > 140 MeV/c 2 . In this particular region low energy QCD contri- butions become important and can be calculated in the framework of Chiral Perturbation Theory (ChPT). From a total number of 1 . 56 × 10 11 recorded kaon decays, the branching ratio is mea- sured to be B ( K ± → μ ± ν μ e + e − | M ee > 140 MeV / c 2 ) = ( 7 . 8 ± 0 . 2 ) × 10 − 8

  3. Present and Future Kaon Physics ( Kaon Decays: Status and Prospects of Experiments)

    Energy Technology Data Exchange (ETDEWEB)

    Bryman, Doug (University of British Columbia)

    2005-05-04

    Study of the ultra-rare K {yields} {pi}{nu}{bar {nu}} decays is highly motivated by their unique theoretical access to short distance physics allowing deep probing of physics beyond the Standard Model including possible new sources of CP violation and flavor symmetry breaking. It also appears that through the development of targeted experimental techniques, both the charged and neutral processes, K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} and K{sub L}{sup 0} {yields} {pi}{sup 0}{nu}{bar {nu}}, are accessible to detailed measurement. Three events consistent with K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} decay have been observed by BNL E787/E949 and further measurements of this reaction are being planned. The new KOPIO experiment at BNL is aiming to study the special CP-violating decay K{sub L}{sup 0} {yields} {pi}{sup 0}{nu}{bar {nu}} with a precision of 10%. The motivations, experimental methods, prospects, and possible impact of KOPIO and other future measurements will be discussed.

  4. A straw drift chamber spectrometer for studies of rare kaon decays

    CERN Document Server

    Lang, K; Arroyo, C; Bachman, M; Connor, D; Eckhause, M; Ecklund, K M; Graessle, S C; Hamela, M; Hamilton, S; Hancock, A D; Hartman, K; Hebert, M; Hoff, C H; Hoffmann, G W; Irwin, G M; Kane, J R; Kanematsu, N; Kuang, Y; Lee, R; Marcin, M; Martin, R D; McDonough, J; Milder, A J; Molzon, W R; Ouimette, D A; Pommot-Maia, M C; Proga, M; Riley, P J; Ritchie, J L; Rubin, P D; Vassilakopoulos, V I; Ware, B; Welsh, R E; Wojcicki, S G; Worm, S

    2004-01-01

    We describe the design, construction, readout, tests, and performance of planar drift chambers, based on 5 mm diameter copperized Mylar and Kapton straws, used in an experimental search for rare kaon decays. The experiment took place in the high-intensity neutral beam at the Alternating Gradient Synchrotron of Brookhaven National Laboratory, using a neutral beam stop, two analyzing dipoles, and redundant particle identification to remove backgrounds.

  5. A straw drift chamber spectrometer for studies of rare kaon decays

    Energy Technology Data Exchange (ETDEWEB)

    Lang, K. E-mail: lang@mail.hep.utexas.edu; Ambrose, D.; Arroyo, C.; Bachman, M.; Connor, D.; Eckhause, M.; Ecklund, K.M.; Graessle, S.; Hamela, M.; Hamilton, S.; Hancock, A.D.; Hartman, K.; Hebert, M.; Hoff, C.H.; Hoffmann, G.W.; Irwin, G.M.; Kane, J.R.; Kanematsu, N.; Kuang, Y.; Lee, R.; Marcin, M.; Martin, R.D.; McDonough, J.; Milder, A.; Molzon, W.R.; Ouimette, D.; Pommot-Maia, M.; Proga, M.; Riley, P.J.; Ritchie, J.L.; Rubin, P.D.; Vassilakopoulos, V.I.; Ware, B.; Welsh, R.E.; Wojcicki, S.G.; Worm, S

    2004-04-21

    We describe the design, construction, readout, tests, and performance of planar drift chambers, based on 5-mm-diameter copperized Mylar and Kapton straws, used in an experimental search for rare kaon decays. The experiment took place in the high-intensity neutral beam at the Alternating Gradient Synchrotron of Brookhaven National Laboratory, using a neutral beam stop, two analyzing dipoles, and redundant particle identification to remove backgrounds.

  6. Observation Of B Meson Decaying To A Neutral Strange Kaon Pion-antipion, And B Meson Decaying To Kaon*(892) Pion- Antipion And Measurement Of The Charge Asymmetry In B Meson Decaying To Kaon*(892) Pion-antipion

    CERN Document Server

    Sun, W M

    2003-01-01

    We report on a search for charmless hadronic B decays to the three-body final states K0S h±π∓, K±h∓π 0, and K0S h±π0 ( h± denotes a charged pion or kaon), using 9.12 fb−1 of integrated luminosity produced at s = 10.58 GeV and collected with the CLEO detector. We observe the decay B → K0/K¯ 0π+π− with a branching fraction ( 50+10-9 ± 7) × 10−6 and the decay B → K*(892)±π ∓ with a branching fraction ( 16+6-5 ± 2) × 10−6, where the uncertainties are statistical and systematic, respectively. Both branching fractions are averages over CP-conjugate states. We also search for a CP-violating asymmetry in the decay B → K*(892)±π∓. We find ACP (B → K*(892)± π∓) = 0.26+0.33+0.10-0.34-0.08 , ...

  7. Weak Phases From B Decays to Kaons and Charged Pions

    OpenAIRE

    1996-01-01

    Phases of elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be obtained using decays of $B$ mesons to $\\pi^+ \\pi^-$, $\\pi^\\pm K^\\mp$, and $\\pi^+ K^0$ or $\\pi^- \\overline{K}^0$. For $B^0~{\\rm or}~ \\overline{B}^0 \\to \\pi^+ \\pi^-$, one identifies the flavor of the neutral $B$ meson at time of production and studies the time-dependence of the decay rate. The other processes are self-tagging and only their rates need be measured. By assuming flavor SU(3) symmetry and first-order SU(3) bre...

  8. Radiative corrections in K --> pi l+ l- decays

    CERN Document Server

    Kubis, Bastian

    2010-01-01

    We calculate radiative corrections to the flavor-changing neutral current process K --> pi l+ l-, both for charged and neutral kaon decays. While the soft-photon approximation is shown to work well for the muon channels, we discuss the necessity of further phase space cuts with electrons in the final state. It is also shown how to transfer our results to other decays such as eta --> gamma l+ l- or omega --> pi0 l+ l-.

  9. Rare and forbidden kaon decays at NA62

    Directory of Open Access Journals (Sweden)

    Pepe Monica

    2015-01-01

    The rare decays K+ → π+νν̅ are excellent processes to make tests of new physics at the highest scale complementary to LHC thanks to their theoretically cleaness. The NA62 experiment at CERN SPS aims to collect of the order of 100 events in two years of data taking, keeping the background at the level of 10%.

  10. Weak phases from B decays to kaons and charged pions

    Science.gov (United States)

    Dighe, Amol S.; Gronau, Michael; Rosner, Jonathan L.

    1996-09-01

    Phases of elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be obtained using decays of B mesons to π+π-, π+/-K-/+, and π+K0 or π-K¯0. For B0 or B¯0-->π+π-, one identifies the flavor of the neutral B meson at time of production and studies the time dependence of the decay rate. The other processes are self-tagging and only their rates need to be measured. By assuming flavor SU(3) symmetry and first-order SU(3) breaking, one can separately determine the phases γ≡Arg V*ub and α=π-β-γ, where β≡Arg V*td. Special cases include the vanishing of strong interaction phase differences between amplitudes, the possibility of recovering partial information when π+π- and π+/-K-/+ decays cannot be distinguished from one another, and the use of a correlation between γ and α in the region of allowed parameters.

  11. Weak phases from B decays to kaons and charged pions

    CERN Document Server

    Dighe, A S; Rosner, Jonathan L; Dighe, Amol S; Gronau, Michael; Rosner, Jonathan L

    1996-01-01

    Phases of elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be obtained using decays of B mesons to \\pi^+ \\pi^-, \\pi^\\pm K^\\mp, and \\pi^+ K^0 or \\pi^- \\overline{K}^0. For B^0~{\\rm or}~ \\overline{B}^0 \\to \\pi^+ \\pi^-, one identifies the flavor of the neutral B meson at time of production and studies the time-dependence of the decay rate. The other processes are self-tagging and only their rates need be measured. By assuming flavor SU(3) symmetry and first-order SU(3) breaking, one can separately determine the phases \\gamma \\equiv {\\rm Arg}~V_{ub}^* and \\alpha = \\pi - \\beta - \\gamma, where \\beta \\equiv {\\rm Arg}~V_{td}^*. Special cases include the vanishing of strong interaction phase differences between amplitudes, the possibility of recovering partial information when \\pi^+ \\pi^- and \\pi^\\pm K^\\mp decays cannot be distinguished from one another, and the use of a correlation between \\gamma and \\alpha in the region of allowed parameters.

  12. Electrons and kaons in charmed particle decays. [Branching ratio, 3. 9 to 7. 4 GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Feller, J.M.

    1979-05-01

    Inclusive studies of the electron content, kaon content, and associated electron-kaon content of the decays of D mesons and other charmed particles produced in electron-positron annihilation are presented. At the psi(3772) resonance the following inclusive branching ratios for D meson decays to charged kaons were measured. Also at the psi(3772) resonance the average semileptonic branching ratio for D/sup 0/ and D/sup +/ decays to electrons has been measured to be .076 +- .028. The average semileptonic branching ratio of charmed particles produced in e/sup +/e/sup -/ annihilation at center-of-mass energies from 3.9 to 7.4 GeV is found to be equal within errors to that of the D's. At all energies the electron momentum spectra are consistent with a combination of the decays D ..-->.. Ke nu and D ..-->.. K*e nu. 84 references.

  13. A precision measurement of direct CP violation in the decay of neutral kaons into two pions

    CERN Document Server

    Batley, J Richard; Gershon, T J; Kalmus, George Ernest; Lazzeroni, C; Munday, D J; Olaiya, E; Patel, M; Parker, M A; White, T O; Wotton, S A; Arcidiacono, R; Barr, Giles David; Bocquet, G; Ceccucci, Augusto; Çuhadar-Dönszelmann, T; Cundy, Donald C; Doble, Niels T; Falaleev, V P; Gatignon, L; Gonidec, A; Gorini, B; Grafström, P; Kubischta, Werner; Mikulec, I; Norton, Alan Robert; Palestini, S; Panzer-Steindel, B; Schinzel, D; Wahl, H; Cheshkov, C; Khristov, P Z; Kekelidze, V D; Madigozhin, D T; Molokanova, N A; Potrebenikov, Yu K; Zinchenko, A I; Rubin, P; Sacco, R; Walker, A; Bettoni, D; Calabrese, R; Dalpiaz, Pietro; Duclos, J; Frabetti, P L; Gianoli, A; Martini, M; Masetti, L; Petrucci, F; Savrié, M; Scarpa, M; Bizzeti, A; Calvetti, M; Collazuol, G; Iacopini, E; Lenti, M; Martelli, F; Ruggiero, G; Veltri, M; Coward, D; Eppard, M; Hirstius, A; Holtz, K; Kleinknecht, K; Koch, U; Köpke, L; Lopes da Silva, P; Marouelli, P; Mestvirishvili, I; Morales, C; Pellmann, I A; Peters, A; Renk, B; Schmidt, S A; Schönharting, V; Wanke, R; Winhart, A; Chollet, J C; Fayard, Louis; Graziani, G; Iconomidou-Fayard, L; Unal, G; Wingerter-Seez, I; Anzivino, Giuseppina; Cenci, P; Imbergamo, E; Lamanna, G; Lubrano, P; Mestvirishvili, A; Nappi, A; Pepé, M; Piccini, M; Valdata-Nappi, M; Casali, R; Cerri, C; Cirilli, M; Costantini, F; Fantechi, R; Fiorini, Luca; Giudici, Sergio; Mannelli, I; Pierazzini, G M; Sozzi, M; Chèze, J B; De Beer, M; Debu, P; Derue, F; Formica, A; Gouge, G; Marel, Gérard; Mazzucato, E; Peyaud, B; Turlay, René; Vallage, B; Holder, M; Maier, A; Ziolkowski, M; Biino, C; Cartiglia, N; Clemencic, M; Marchetto, F; Menichetti, E; Pastrone, N; Nassalski, J P; Rondio, Ewa; Wislicki, W; Wronka, S; Dibon, Heinz; Jeitler, Manfred; Markytan, Manfred; Neuhofer, Günther; Pernicka, Manfred; Taurok, Anton; Widhalm, L

    2002-01-01

    The direct CP violation parameter Re($\\epsilon'/\\epsilon)$ has been measured from the decay rates of neutral kaons into two pions using the NA48 detector at the CERN SPS. The 2001 running period was devoted to collecting additional data under varied conditions compared to earlier years (1997-99). The new data yield the result: Re($\\epsilon'/\\epsilon)$=$(13.7\\pm3.1)\\ times10^{-4}$. Combining this result with that published from the 1997 98 and 99 data, an overall value of Re($\\epsilon'/\\epsilon)$=$(14.7\\pm2.2)\\times10^{-4 }$ is obtained from the NA48 experiment.

  14. A study of T violation via the semileptonic decays of neutral kaons in CPLEAR

    Energy Technology Data Exchange (ETDEWEB)

    Adler, R.; Alhalel, T.; Angelopoulos, A.; Apostolakis, A.; Aslanides, E.; Backenstoss, G.; Bee, C.P.; Bennet, J.; Bertin, V.; Bienlein, J.K.; Bloch, P.; Bula, C.; Carlson, P.; Carvalho, J.; Cawley, E.; Charalambous, S.; Chardalas, M.; Chardin, G.; Danielsson, M.; Dedoussis, S.; Dejardin, M.; Derre, J.; Dodgson, M.; Dousse, J.C.; Duclos, J.; Ealet, A.; Eckart, B.; Eleftheriadis, C.; Evangelou, I.; Faravel, L.; Fassnacht, P.; Faure, J.L.; Felder, C.; Ferreira-Marques, R.; Fetscher, W.; Fidecaro, M.; Filipcic, A.; Francis, D.; Fry, J.; Fuglesang, C.; Gabathuler, E.; Gamet, R.; Garreta, D.; Geralis, T.; Gerber, H.J.; Go, A.; Gumplinger, P.; Guyot, C.; Harrison, P.F.; Hayman, P.J.; Heyes, W.G.; Hollander, R.W.; Jansson, K.; Johner, H.J.; Jon-And, K.; Kerek, A.; Kern, J.; Kettle, P.R.; Kochowski, C.; Kokkas, P.; Kreuger, R.; Lawry, T.; Le Gac, R.; Liolios, A.; Machado, E.; Maley, P.; Mandic, I.; Manthos, N.; Marel, G.; Mikuz, M.; Miller, J.; Montanet, F.; Nakada, T.; Onofre, A.; Pagels, B.; CPLEAR Collaboration

    1993-06-07

    The method for studying semileptonic neutral kaon decays at CPLEAR is presented together with a preliminary data analysis. For the first time a direct determination of T violation is shown to be possible and low statistics results are given. From the same data the K[sub L]-K[sub S] mass difference, [Delta]m, the Cp violation parameter of K[sub S], [epsilon][sub S], and the parameter x testing the [Delta]S=[Delta]Q rule are also obtained. (orig.)

  15. Study of $\\tau$ decays involving kaons, spectral functions and determination of the strange quark mass

    CERN Document Server

    Barate, R; Ghez, P; Goy, C; Lees, J P; Merle, E; Minard, M N; Pietrzyk, B; Alemany, R; Casado, M P; Chmeissani, M; Crespo, J M; Fernández, E; Fernández-Bosman, M; Garrido, L; Graugès-Pous, E; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Pacheco, A; Park, I C; Riu, I; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Becker, U; Boix, G; Cattaneo, M; Ciulli, V; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Halley, A W; Hansen, J B; Harvey, J; Janot, P; Jost, B; Lehraus, Ivan; Leroy, O; Mato, P; Minten, Adolf G; Moutoussi, A; Ranjard, F; Rolandi, Luigi; Rousseau, D; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Teubert, F; Tomalin, I R; Tournefier, E; Ajaltouni, Ziad J; Badaud, F; Chazelle, G; Deschamps, O; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Bonneaud, G R; Brient, J C; Rougé, A; Rumpf, M; Swynghedauw, M; Verderi, M; Videau, H L; Focardi, E; Parrini, G; Zachariadou, K; Cavanaugh, R J; Corden, M; Georgiopoulos, C H; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Cerutti, F; Chiarella, V; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Lynch, J G; Negus, P; O'Shea, V; Raine, C; Teixeira-Dias, P; Thompson, A S; Buchmüller, O L; Dhamotharan, S; Geweniger, C; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Marinelli, N; Sedgbeer, J K; Spagnolo, P; Thomson, E; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Buck, P G; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Robertson, N A; Williams, M; Giehl, I; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Wachsmuth, H W; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Carr, J; Coyle, P; Etienne, F; Ealet, A; Motsch, F; Payre, P; Talby, M; Thulasidas, M; Aleppo, M; Antonelli, M; Ragusa, F; Berlich, R; Büscher, V; Dietl, H; Ganis, G; Hüttmann, K; Lütjens, G; Mannert, C; Männer, W; Moser, H G; Schael, S; Settles, Ronald; Seywerd, H C J; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Schune, M H; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Bettarini, S; Boccali, T; Bozzi, C; Calderini, G; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Giassi, A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sciabà, A; Sguazzoni, G; Tenchini, Roberto; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Chambers, J T; Cowan, G D; Green, M G; Medcalf, T; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Konstantinidis, N P; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Foss, J; Grupen, Claus; Prange, G; Smolik, L; Stephan, F; Giannini, G; Gobbo, B; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; Gao, Y; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; Mamier, G; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Vogt, M; Walsh, J; Wu Sau Lan; Wu, X; Zobernig, G

    1999-01-01

    All ALEPH measurements of branching ratios of tau decays involving kaons are summarized including a combination of results obtained with K^0_S and K^0_L detection. The decay dynamics are studied, leading to the determination of contributions from vector K^*(892) and K^{*}(1410), and axial-vector K_1(1270) and K_1(1400) resonances. Agreement with isospin symmetry is observed among the different final states. Under the hypothesis of the conserved vector current, the spectral function for the K\\bar{K}\\pi mode is compared with the corresponding cross section for low energy e^+e^- annihilation, yielding an axial-vector fraction of (94^{+6}_{-8})% for this mode. The branching ratio for tau decay into all strange final states is determined to be B(\\tau^-\\to X^-(S=-1)\

  16. Lessons learned from E871, a search for rare Kaon decays at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, M. [Department of Physics and Astronomy, University of California at Irvine, Irvine, California 92697-4575 (United States)

    1998-08-01

    E871 at the Brookhaven Alternating Gradient Synchrotron (BNL AGS) searched for the rare decays of the neutral Kaon, K{sub L}{r_arrow}{mu}{mu}, K{sub L}{r_arrow}ee, K{sub L}{r_arrow}{mu}e. Data were taken during two run periods in 1995 and 1996 resulting in an expected single event sensitivity of {approximately}10{sup {minus}12}. Over 6,000 K{sub L}{r_arrow}{mu}{mu} events have been seen in the data. The E871 collaboration is currently concluding its analysis of these decays and results are expected to be published shortly. Experimental technique, as well as problems associated with the measurement of these rare processes in a high rate environment is discussed. {copyright} {ital 1998 American Institute of Physics.}

  17. Panofsky Prize Talk: Measurements of Direct CP Violation in the Decays of Neutral Kaons at Fermilab

    Science.gov (United States)

    Winstein, Bruce

    2007-04-01

    For many years after its discovery, CP Violation appeared to be a phenomenon isolated from the rest of physics. The first goal was to see if tCP violation was due to a ``superweak'' interaction in neutral kaon mixing (``indirect'' CP violation) or if there were a ``direct'' effect which would be manifest in the kaon decays themselves. For years, it seemed to be an interaction of the former kind, one that might not have any additional manifestations. A few years after the discovery, Sakharov realized that CP Violation in the very early Universe, in particular direct CP Violation, could lead to the matter-antimatter imbalance. A key development was the Kobayashi-Maskawa model which provided a framework in which to think about the problem, connecting it to quark mixing. This motivated a series of 2nd, 3rd, and 4th generation experiments to isolate the predicted direct effect. This talk will review how the problem was addressed in 3 Fermilab- based experiments spanning a 20 year period which culminated in a definitive detection of the effect by KTeV. The motivation and technical approaches to isolate this tiny effect with good control of systematic uncertainty will be reviewed together with the results and future prospects.

  18. Probing a dark photon using rare leptonic kaon and pion decays

    Science.gov (United States)

    Chiang, Cheng-Wei; Tseng, Po-Yan

    2017-04-01

    Rare leptonic kaon and pion decays K+ (π+) →μ+νμe+e- can be used to probe a dark photon of mass O (10) MeV, with the background coming from the mediation of a virtual photon. This is most relevant for the 16.7-MeV dark photon proposed to explain a 6.8σ anomaly recently observed in 8Be transitions by the Atomki Collaboration. We evaluate the reach of future experiments for the dark photon with vectorial couplings to the standard model fermions except for the neutrinos, and show that a great portion of the preferred 16.7-MeV dark photon parameter space can be decisively probed. We also show the use of angular distributions to further distinguish the signal from the background.

  19. Probing a dark photon using rare leptonic kaon and pion decays

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Chiang

    2017-04-01

    Full Text Available Rare leptonic kaon and pion decays K+(π+→μ+νμe+e− can be used to probe a dark photon of mass O(10 MeV, with the background coming from the mediation of a virtual photon. This is most relevant for the 16.7-MeV dark photon proposed to explain a 6.8σ anomaly recently observed in 8Be transitions by the Atomki Collaboration. We evaluate the reach of future experiments for the dark photon with vectorial couplings to the standard model fermions except for the neutrinos, and show that a great portion of the preferred 16.7-MeV dark photon parameter space can be decisively probed. We also show the use of angular distributions to further distinguish the signal from the background.

  20. Trigger for rare kaon decays searches at the CERN NA62 experiment

    CERN Document Server

    Angelucci, Bruno

    The work reported in this thesis has been carried out within the Trigger and Data Ac- quisition (TDAQ) working group of the CERN NA62 experiment, and focused on the development of a trigger strategy for collecting rare kaon decays. The main aim of the NA62 experiment is the study of the ultra rare decay K + ! + in order to provide a stringent test of the Standard Model. The theoretical framework of the K + ! + decay, the present experimental status of the measurement of the Branching Ratio and the NA62 experimental strategy are described in chapter 1. Chapter 2 provides a description of the NA62 experimental setup. The first part of the work concerned the design, development and assessment of the common Trigger and Data Acquisition system for the majority of detectors in NA62, a high-speed integrated data acquisition and trigger generation system based on digital high resolution time measurements. The architecture of the boards, a detailed description of the devel- oped firmwares and some results obta...

  1. Kaon interferometry

    CERN Document Server

    Heinz, Ulrich W; Wiedemann, Urs Achim; Wu Yuang Fang

    1996-01-01

    Two-kaon and two-pion correlation functions for an expanding thermalized source are compared. In the Yano-Koonin-Podgoretskii parametrization of the correlation function, the HBT radius parameters are shown to obey M_\\bot- scaling in the absence of collective transverse flow. This scaling is broken by transverse flow. An accurate comparison of pion and kaon correlations can thus resolve issue whether the observed M_\\bot-dependence of the transverse radius parameter is due to transverse collective flow or other transverse gradients. Effects from resonance decays are shortly discussed.

  2. An evaluation of |Vus| and precise tests of the Standard Model from world data on leptonic and semileptonic kaon decays

    CERN Document Server

    Antonelli, M; Isidori, G; Mescia, F; Moulson, M; Neufeld, H; Passemar, E; Palutan, M; Sciascia, B; Sozzi, M; Wanke, R; Yushchenko, O P

    2010-01-01

    We present a global analysis of leptonic and semileptonic kaon decay data, including all recent results published by the BNL-E865, KLOE, KTeV, ISTRA+ and NA48 experiments. This analysis, in conjunction with precise lattice calculations of the hadronic matrix elements now available, leads to a very precise determination of |Vus| and allows us to perform several stringent tests of the Standard Model.

  3. First exploratory calculation of the long-distance contributions to the rare kaon decays $K\\to\\pi\\ell^+\\ell^-$

    CERN Document Server

    Christ, Norman H; Juttner, Andreas; Lawson, Andrew; Portelli, Antonin; Sachrajda, Christopher T

    2016-01-01

    The rare decays of a kaon into a pion and a charged lepton/antilepton pair proceed via a flavour changing neutral current and therefore may only be induced beyond tree level in the Standard Model. This natural suppression makes these decays sensitive to the effects of potential New Physics. The CP conserving $K\\to\\pi \\ell^+\\ell^-$ decay channels however are dominated by a single photon exchange; this involves a sizeable long-distance hadronic contribution which represents the current major source of theoretical uncertainty. Here we outline our methodology for the computation of the long-distance contributions to these rare decay amplitudes using lattice QCD and present the numerical results of the first exploratory studies of these decays in which all but the disconnected diagrams are evaluated. The domain wall fermion ensembles of the RBC and UKQCD collaborations are used, with a pion mass of $M_{\\pi}\\sim 430\\,\\mathrm{MeV}$ and a kaon mass of $M_{K}\\sim 625\\,\\mathrm{MeV}$. In particular we determine the form...

  4. Extraction of Kaon Formfactors from K->mu nu gamma Decay at ISTRA+ Setup

    CERN Document Server

    Duk, V A; Lebedev, V A; Khudyakov, A A; Makarov, A I; Polyarush, A Yu; Novikov, V P; Akimenko, S A; Britvich, G I; Filin, A P; Inyakin, A V; Korolkov, I Ya; Leontiev, V M; Obraztsov, V F; Polyakov, V A; Romanovsky, V I; Tchikilev, O G; Uvarov, V A; Yushchenko, O P

    2010-01-01

    The radiative decay K->mu nu gamma has been studied at ISTRA+ setup in a new kinematical region. About 46K events of K->mu nu gamma have been observed. The sign and value of Fv-Fa have been measured for the first time. The result is Fv-Fa=0.16(4)(5).

  5. CP violation and kaon-pion interactions in B {r_arrow} K {pi}{sup +}{pi}{sup -} decays.

    Energy Technology Data Exchange (ETDEWEB)

    El-Bennich, B.; Furman, A.; Kaminski, R.; Lesniak, L.; Loiseau, B.; Moussallam, B.; Physics; Univ. Pierre et Marie Curie; ul. Bronowicka; Polish Academy of Sciences; Univ. Paris-Sud

    2009-01-01

    We study CP violation and the contribution of the strong kaon-pion interactions in the three-body B {yields} Kpi{sup +}pi{sup -} decays. We extend our recent work on the effect of the two-pion S- and P-wave interactions to that of the corresponding kaon-pion ones. The weak amplitudes have a first term derived in QCD factorization and a second one as a phenomenological contribution added to the QCD penguin amplitudes. The effective QCD coefficients include the leading order contributions plus next-to-leading order vertex and penguins corrections. The matrix elements of the transition to the vacuum of the kaon-pion pairs, appearing naturally in the factorization formulation, are described by the strange Kpi scalar (S-wave) and vector (P-wave) form factors. These are determined from Muskhelishvili-Omnes coupled channel equations using experimental kaon-pion T-matrix elements, together with chiral symmetry and asymptotic QCD constraints. From the scalar form factor study, the modulus of the K*{sub 0}(1430) decay constant is found to be (32 {+-} 5) MeV. The additional phenomenological amplitudes are fitted to reproduce the Kpi effective mass and helicity angle distributions, the B {yields} K*(892)pi branching ratios and the CP asymmetries of the recent data from Belle and BABAR collaborations. We use also the new measurement by the BABAR group of the phase difference between the B{sup 0} and [overline B]{sup 0} decay amplitudes to K*(892)pi. Our predicted B{sup {+-}} {yields} K*{sub 0}(1430)pi{sup {+-}}, K*{sub 0}(1430) {yields} K{sup {+-}}pi{sup {-+}} branching fraction, equal to (11.6 {+-} 0.6) x 10{sup -6}, is smaller than the result of the analyzes of both collaborations. For the neutral B{sup 0} decays, the predicted value is (11.1 {+-} 0.5) x 10{sup -6}. In order to reduce the large systematic uncertainties in the experimental determination of the B {yields} K*{sub 0}(1430)pi branching fractions, a new parametrization is proposed. It is based on the Kpi scalar

  6. Measurement of charged kaon semileptonic decay branching fractions and their ratio at the NA-48/2 experiment at CERN

    CERN Document Server

    Dabrowski, Anne Evelyn

    2007-01-01

    Measurements of the ratios of charged kaon decay rates for Ke3/K2 π, K μ 3/K2 π and K μ 3/Ke3 are presented. These measurements are based on charged kaon decays collected in a dedicated run in 2003 by the NA48/2 experiment at CERN. The results obtained are Ke3/K2 π = 0.2470 ± 0.0009 ( stat ) ± 0.0004 ( syst ) and K μ 3/K2 π = 0.1637 ± 0.0006 ( stat ) ± 0.0003 ( syst ). Using the PDG average for the K2pi normalization mode, both values are found to be larger than the current values given by the Particle Data Book and lead to a larger magnitude of the V us parameter in the Cabibbo-Kobayashi-Maskawa (CKM) matrix than previously accepted. When combined with the latest Particle Data Book value of | V ud |, | V us | is in agreement with unitarity of the CKM matrix. A new measured value of the ratio of the semileptonic decay rates, K μ 3/Ke3 = 0.663 ± 0.003(stat) ± 0.001(syst) is compared to semi-empirical predictions based on the latest form factor measurements.

  7. Kaon semileptonic decay form factors from N{sub f} = 2 non-perturbatively O(a)-improved Wilson fermions

    Energy Technology Data Exchange (ETDEWEB)

    Broemmel, D. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Regensburg Univ. (Germany). Inst. fuer Physik 1 - Theoretische Physik; Horsley, R.; Zanotti, J. [Edinburgh Univ. (United Kingdom). School of Physics; Morozov, S.M. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Nakamura, Y.; Pleiter, D. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Stueben, H. [Konrad-Zuse-Zentrum fuer Informationstechnik Berlin (ZIB) (Germany)

    2007-10-15

    We present first results from the QCDSF collaboration for the kaon semileptonic decay form factors at zero momentum transfer, using two flavours of non-perturbatively O(a)-improved Wilson quarks. A lattice determination of these form factors is of particular interest to improve the accuracy on the CKM matrix element vertical stroke V{sub us} vertical stroke. Calculations are performed on lattices with lattice spacing of about 0.08 fm with different values of light and strange quark masses, which allows us to extrapolate to chiral limit. Employing double ratio techniques, we are able to get small statistical errors. (orig.)

  8. Search for Proton Decay into Muon plus Neutral Kaon in Super-Kamiokande I, II, and III

    CERN Document Server

    Regis, C; Hayato, Y; Iyogi, K; Kameda, J; Koshio, Y; Marti, Ll; Miura, M; Moriyama, S; Nakahata, M; Nakayama, S; Obayashi, Y; Sekiya, H; Shiozawa, M; Suzuki, Y; Takeda, A; Takenaga, Y; Ueno, K; Yokozawa, T; Kaji, H; Kajita, T; Kaneyuki, K; Lee, K P; Okumura, K; McLachlan, T; Labarga, L; Kearns, E; Raaf, J L; Stone, J L; Sulak, L R; Goldhaber, M; Bays, K; Carminati, G; Kropp, W R; Mine, S; Renshaw, A; Smy, M B; Sobel, H W; Ganezer, K S; Hill, J; Keig, W E; Jang, J S; Kim, J Y; Lim, I T; Albert, J B; Scholberg, K; Walter, C W; Wendell, R A; Wongjirad, T; Ishizuka, T; Tasaka, S; Learned, J G; Matsuno, S; Smith, S N; Hasegawa, T; Ishida, T; Ishii, T; Kobayashi, T; Nakadaira, T; Nakamura, K; Nishikawa, K; Oyama, Y; Sakashita, K; Sekiguchi, T; Tsukamoto, T; Suzuki, A T; Takeuchi, Y; Ieki, K; Ikeda, M; Kubo, H; Minamino, A; Murakami, A; Nakaya, T; Fukuda, Y; Choi, K; Itow, Y; Mitsuka, G; Miyake, M; Mijakowski, P; Hignight, J; Imber, J; Jung, C K; Taylor, I; Yanagisawa, C; Ishino, H; Kibayashi, A; Mori, T; Sakuda, M; Takeuchi, J; Kuno, Y; Kim, S B; Okazawa, H; Choi, Y; Nishijima, K; Koshiba, M; Totsuka, Y; Yokoyama, M; Martens, K; Vagins, M R; Chen, S; Sui, H; Yang, Z; Zhang, H; Connolly, K; Dziomba, M; Wilkes, R J

    2012-01-01

    We have searched for proton into muon plus neutral kaon using data from a 91.7 kiloton-year exposure of Super-Kamiokande-I, a 49.2 kiloton-year exposure of Super-Kamiokande-II, and a 31.9 kiloton-year exposure of Super-Kamiokande-III. The number of candidate events in the data was consistent with the atmospheric neutrino background expectation and no evidence for proton decay in this mode was found. We set a partial lifetime lower limit of 1.6x10^33 years at the 90% confidence level.

  9. Four-body Dalitz plot contribution to the radiative corrections in K_{l3}^0 decays and its role in the determination of |V_{us}|

    CERN Document Server

    Neri, M; Juarez-Leon, C; Torres, J J; Flores-Mendieta, Ruben

    2016-01-01

    The four-body contribution of the model-independent radiative corrections to the Dalitz plot of the semileptonic decays of neutral kaons are computed to order (\\alpha/\\pi)(q/M_1), where q is the momentum transfer and M_1 is the kaon mass. The final result is presented in two forms. The first one is given in terms of the triple integration of the bremsstrahlung photon ready to be performed numerically; the second one is a fully analytical expression. This paper is organized to make it accessible and reliable in the analysis of the Dalitz plot of precision experiments involving kaons and is not compromised to fixing the form factors at predetermined values. As a byproduct, gathering together three- and four-body contributions of radiative corrections yields, through a least-squares fit to the measured kaon decay rates, the value f_+^{K^0\\pi^-}|V_{us}| = 0.2168(3).

  10. Kaon to Two Pions decays from Lattice QCD: Delta I = 1/2 rule and CP violation

    Science.gov (United States)

    Liu, Qi

    We report a direct lattice calculation of the K to pipi decay matrix elements for both the DeltaI=1/2 and 3/2 amplitudes A0 and A2 on a 2+1 flavor, domain wall fermion, 163x32x16 lattice ensemble and a 243x64x16 lattice ensemble. This is a complete calculation in which all contractions for the required ten, four-quark operators are evaluated, including the disconnected graphs in which no quark line connects the initial kaon and final two-pion states. These lattice operators are non-perturbatively renormalized using the Rome-Southampton method and the quadratic divergences are studied and removed. This is an important but notoriously difficult calculation, requiring high statistics on a large volume. In this work we take a major step towards the computation of the physicalK→pipi amplitudes by performing a complete calculation at unphysical kinematics with pions of mass 422 MeV and 329 MeV at rest in the kaon rest frame. With this simplification we are able to resolve Re(A0) from zero for the first time, with a 25% statistical error on the 163 lattice and 15% on the 243 lattice. The complex amplitude A2 is calculated with small statistical errors. We obtain the DeltaI=1/2 rule with an enhancement factor of 9.1(21) and 12.0(17) on these two ensembles. From the detailed analysis of the results we gain a deeper understanding of the origin of the DeltaI=1/2 rule. We also calculate the complex amplitude A0, a calculation central to understanding and testing the standard model of CP violation in the kaon system. The final result for the measure of direct CP violation, epsilon', calculated at unphysical kinematics has an order of 100% statistical error, so this only serves as an order of magnitude check.

  11. Probing the SUSY with $10$ TeV stop mass in rare decays and CP violation of Kaon

    CERN Document Server

    Tanimoto, Morimitsu

    2016-01-01

    We probe the SUSY with the stop mass of ${\\mathcal O}(10)$ TeV in the rare decays and the CP violation of kaon. We take the split-family model of the SUSY in which the third family of squarks/sleptons is heavy, ${\\cal O}(10)$ TeV, while the first and second ones of squarks/sleptons and the gauginos have relatively low masses ${\\cal O}(1)$ TeV. We also consider the high-scale SUSY model, in which all squarks/sleptons and the gauginos are at the ${\\cal O}(10)$ TeV scale. In both frameworks, we study $K_L \\to \\pi^0 \

  12. Measurement of Branching Fractions for Two-Body Charmless B Decays to Charged Pions and Kaons at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, Barbara

    2000-08-28

    The authors present preliminary results of a search for charmless two-body B decays to charged pions and kaons using data collected by the BaBar detector at the Stanford Linear Accelerator Center's PEP-II Storage ring. In a sample of 8.8 million produced B anti-B pairs the authors measure the branching fractions beta(B{sup 0} --> pi{sup +}pi{sup {minus}}) = (9.3{sub {minus}2.3{minus}1.4}{sup +2.6+1.2}) x 10{sup {minus}6} and beta(B{sup 0} --> K{sup +}pi{sup {minus}}) = (12.5{sub {minus}2.6{minus}1.7}{sup +3.0+1.3}) x 10{sup {minus}6}, where the first uncertainty is statistical and the second is systematic. For the decay B{sup 0} --> K{sup +}K{sup {minus}} they find no significant signal and set an upper limit of beta(B{sup 0} --> K{sup +}K{sup {minus}}) < 6.6 x 10{sup {minus}6} at the 90% confidence level.

  13. Optimization and calibration of the same-side kaon tagging algorithm using hadronic $B_{s}^{0}$ decays in 2011 data

    CERN Document Server

    The LHCb Collaboration

    2012-01-01

    We report on the optimization and calibration of the same-side kaon tagging algorithm using the decay $B_{s}^{0} \\rightarrow D_{s}^{- \\pi^{+}}$ with 1.0~$\\mathrm{fb}^{-1}$ of data from the LHCb 2011 physics run. After a data-driven optimization and calibration, we measured an effective tagging efficiency for the same-side tagger of $(1.5\\pm0.4)%$ using event-by-event predicted mistag for $B_{s}^{0} \\rightarrow D_{s}^{- \\pi^{+}}$ decays. For the combination of same-side kaon and opposite-side taggers the corresponding effective tagging efficiency is $(3.8\\pm0.7)%$ using event-by-event predicted mistag in this channel.

  14. An evaluation of vertical stroke V{sub us} vertical stroke and precise tests of the standard model from world data on leptonic and semileptonic kaon decays

    Energy Technology Data Exchange (ETDEWEB)

    Antonelli, M.; Isidori, G.; Moulson, M.; Palutan, M.; Sciascia, B. [Laboratori Nazionali di Frascati dell' INFN, Frascati, RM (Italy); Cirigliano, V. [Los Alamos National Laboratory, Theoretical Division, Los Alamos, NM (United States); Mescia, F. [Universitat de Barcelona, Dep. ECM and ICC, Barcelona (Spain); Neufeld, H. [Universitaet Wien, Fakultaet fuer Physik, Vienna (Austria); Passemar, E. [Universitat de Valencia - CSIC, Departament de Fisica Teorica, IFIC, Valencia (Spain); Sozzi, M. [Universita di Pisa e Sezione dell' INFN di Pisa, Dipartimento di Fisica, Pisa (Italy); Wanke, R. [Universitaet Mainz, Institut fuer Physik, Mainz (Germany); Yushchenko, O.P. [Institute for High Energy Physics, Protvino (Russian Federation)

    2010-10-15

    We present a global analysis of leptonic and semileptonic kaon decay data, including all recent results published by the BNL-E865, KLOE, KTeV, ISTRA+ and NA48 experiments. This analysis, in conjunction with precise lattice calculations of the hadronic matrix elements now available, leads to a very precise determination of vertical stroke V{sub us} vertical stroke and allows us to perform several stringent tests of the standard model. (orig.)

  15. LHCb: Radiative Decays at LHCb

    CERN Multimedia

    Orlandea, M

    2013-01-01

    In this work we present a measurement of the ratio of the branching fraction of the radiative decays $B^{0}\\rightarrow K^{*0}\\gamma$ and $B^{0}_{s}\\rightarrow \\phi\\gamma$ using 1.0 fb$^{-1}$ of data taken with the LHCb detector. The value obtained is \\begin{equation} \\frac{B\\left(B^{0}\\rightarrow K^{*0}\\gamma\\right)}{B\\left(B^{0}_{s}\\rightarrow \\phi\\gamma\\right)}=1.23\\pm0.06(stat.)\\pm0.04(syst.)\\pm0.10\\left(f_s/f_d\\right) \\end{equation} Using the world average value $B\\left(B^{0}\\rightarrow K^{*0}\\gamma\\right)=\\left(4.33\\pm0.15\\right)\\times10^{-5}$ branching fraction is determined to be $B\\left(B^{0}_{s}\\rightarrow \\phi\\gamma\\right)=3.5\\pm0.4\\times10^{-5}$. A measurement of the direct CP asymmetry of the decay $B^{0}\\rightarrow K^{*0}\\gamma$ is also presented. Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations.

  16. Measurements of CP-violating asymmetries and branching fractions in the decays of B mesons to charged pions and kaons at the Babar detector

    Science.gov (United States)

    Danielson, Morris Nicholas

    This dissertation describes the measurement of branching fractions and CP asymmetries in neutral B meson decays to charmless two-body final states of charged pions and kaons. CP violation is a poorly-constrained phenomenon in the Standard Model (SM) of particle physics and had been studied only in the kaon system before the Babar and Belle experiments. The decay of the neutral B meson to charged pions and kaons is particularly useful for the study of CP violation because they can be related to the Unitarity Triangle angle alpha. We use an extended maximum likelihood technique that incorporates kinematic, event-shape, and particle identification information to measure the branching fractions of the neutral B meson to pipi, Kpi. These branching fractions are found to be (5.6 +/- 0.4 +/- 0.3) x 10-6 and (19.2 +/- 0.6 +/- 0.6) x 10 -6 respectively. The decay to KK is found to have a branching fraction of less than 0.4 x 10-6 at the 90% confidence level. We also measure the direct CP-violating asymmetry between decays to K+pi- and K-pi+ to be -0.133 +/- 0.030 +/- 0.009. Decay time information and b quark flavor information are then added to determine the time-dependent CP violation parameters S and C, which we find to be -0.30 +/- 0.17 +/- 0.03 and -0.09 +/- 0.15 +/- 0.04, respectively. For all measurements above the first error is statistical and the second is systematic. The results are obtained from a data sample of 227 million decays of the Υ(4S) to B0 B¯z collected between 1999 and 2004 with the Babar detector at the PEP-II asymmetric B factory located at the Stanford Linear Accelerator Center.

  17. Pseudoscalar decay constants of kaon and D-mesons from Nf=2 twisted mass Lattice QCD

    CERN Document Server

    Blossier, B; Frezzotti, R; Haas, B; Herdoiza, G; Jansen, K; Lubicz, V; Mescia, F; Palao, D; Shindler, A; Simula, S; Tarantino, C; Urbach, C; Wenger, U

    2009-01-01

    We present the results of a lattice QCD calculation of the pseudoscalar meson decay constants fpi, fK, fD and fDs, performed with Nf=2 dynamical fermions. The simulation is carried out with the tree-level improved Symanzik gauge action and with the twisted mass fermionic action at maximal twist. We have considered for the final analysis three values of the lattice spacing, a~0.10 fm, 0.09 fm and 0.07 fm, with pion masses down to mpi~270 MeV. Our results for the light meson decay constants are fK=158.1(2.4) MeV and fK/fpi=1.210(18). From the latter ratio, by using the experimental determination of Gamma(K-->mu nu_mu (gamma))/ Gamma(pi--> mu nu_mu (gamma)) and the average value of |Vud| from nuclear beta decays, we obtain |Vus|=0.2222(34), in good agreement with the determination from semileptonic Kl3 decays and the unitarity constraint. For the D and Ds meson decay constants we obtain fD=197(9) MeV, fDs=244(8) MeV and fDs/fD=1.24(3). Our result for fD is in good agreement with the CLEO experimental measurement...

  18. Study of D 0 and D + decays into final states with two or three kaons

    Science.gov (United States)

    Albrecht, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Mankel, R.; Nau, A.; Nowak, S.; Reßing, D.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Hast, C.; Kapitza, H.; Kolanoski, H.; Kosche, A.; Lange, A.; Lindner, A.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Wegener, D.; Eckstein, P.; Schmidtler, M.; Schramm, M.; Schubert, K. R.; Schwierz, R.; Waldi, R.; Reim, K.; Wegener, H.; Eckmann, R.; Kuipers, H.; Mai, O.; Mundt, R.; Oest, T.; Reiner, R.; Schmidt-Parzefall, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hofmann, W.; Hüpper, A.; Knöpfle, K. T.; Spengler, J.; Krieger, P.; Macfarlane, D. B.; Prentice, J. D.; Saull, P. R. B.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Frankl, C.; Schneider, M.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Balagura, V.; Barsuk, S.; Belyaev, I.; Chechelnitsky, S.; Chistov, R.; Danilov, M.; Droutskoy, A.; Gershtein, Yu.; Golutvin, A.; Korolko, I.; Kostina, G.; Litvintsev, D.; Lubimov, V.; Pakhlov, P.; Semenov, S.; Snizhko, A.; Tichomirov, I.; Zaitsev, Yu.

    1994-09-01

    Using the ARGUS detector at the e + e - storage ring DORIS II, we have studied Cabibbo-suppressed D 0 decay modes resulting in the K + K - π + π - final state and two-body D 0 decay modes with a ϕ meson in the final state. The BR( D 0→ K {/S 0} K {/S 0}π+π- was measured for the first time. We also present a measurement of the D + →K {/S 0} K {/S 0} K + branching ratio. The values are compared with other experimental results and model predictions.

  19. A new measurement of direct CP violation in two pion decays of the neutral kaon

    CERN Document Server

    Fanti, V; Marras, D; Musa, L; Bevan, A V; Gershon, T J; Hay, B; Moore, R W; Moore, K N; Munday, D J; Needham, M D; Parker, M A; Takach, S F; White, T O; Wotton, S A; Barr, Giles David; Blümer, H; Bocquet, G; Bremer, J; Ceccucci, Augusto; Cogan, J; Cundy, Donald C; Doble, Niels T; Funk, W; Gatignon, L; Gianoli, A; Gonidec, A; Govi, G; Grafström, P; Kesseler, G; Kubischta, Werner; Lacourt, A; Luitz, S; Matheys, J P; Norton, Alan Robert; Palestini, S; Panzer-Steindel, B; Peyaud, B; Schinzel, D; Taureg, Hans; Velasco, M; Vossnack, O; Wahl, H; Wirrer, G; Gaponenko, A N; Kekelidze, V D; Madigozhin, D T; Mestvirishvili, A; Potrebenikov, Yu K; Tatishvili, G T; Tkachev, A L; Zinchenko, A I; Bertolotto, L; Boyle, O; Knowles, I G; Martin, V J; Parsons, H; Peach, Kenneth J; Talamonti, C; Contalbrigo, M; Dalpiaz, Pietro; Duclos, J; Formica, A; Frabetti, P L; Martini, M; Petrucci, F; Savrié, M; Bizzeti, A; Calvetti, M; Collazuol, G; Graziani, G; Iacopini, E; Lenti, M; Michetti, A; Becker, H G; Buchholz, P; Coward, D H; Ebersberger, C; Fox, H; Kalter, A; Kleinknecht, K; Koch, U; Köpke, L; Renk, B; Scheidt, J; Schmidt, J; Schönharting, V; Schué, Yu; Wilhelm, R; Wittgen, M; Chollet, J C; Crépé, S; Fayard, Louis; Iconomidou-Fayard, L; Ocariz, J; Unal, G; Vattolo, D; Wingerter-Seez, I; Anzivino, Giuseppina; Bordacchini, F; Cenci, P; Lubrano, P; Nappi, A; Pepé, M; Punturo, M; Bertanza, L; Bigi, A; Calafiura, P; Carosi, R; Casali, R; Cerri, C; Cirilli, M; Costantini, F; Fantechi, R; Giudici, Sergio; Gorini, B; Mannelli, I; Marzulli, V M; Pierazzini, G M; Raffaelli, F; Sozzi, M; Chèze, J B; De Beer, M; Debu, P; Granier de Cassagnac, R; Khristov, P Z; Mazzucato, E; Schanne, S; Turlay, René; Vallage, B; Augustin, I; Bender, M; Holder, M; Ziolkowski, M; Arcidiacono, R; Biino, C; Cester, R; Marchetto, F; Menichetti, E; Pastrone, N; Nassalski, J P; Rondio, Ewa; Szleper, M; Wislicki, W; Wronka, S; Dibon, Heinz; Fischer, G; Jeitler, Manfred; Markytan, Manfred; Mikulec, I; Neuhofer, Günther; Pernicka, Manfred; Taurok, Anton

    1999-01-01

    The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting $kl$ and $ks$ decays into $pipin$ and $pipic$. The result for the CP violating parameter $ epr$ is $(18.5 pm 4.5 mathrm{(stat)} pm 5.8 mathrm{(syst)}) imes10^{-4}$.

  20. Symmetry violating kaon decays. [Muon number violation, review, T, and CPT invariance

    Energy Technology Data Exchange (ETDEWEB)

    Herczeg, P.

    1979-01-01

    An analysis of the muon number violating decay modes of the K-mesons is given. Subsequently, some new developments in the field of CP-violation are reviewed and the question of time-reversal invariance and the status of CPT-invariance are briefly considered. 42 references.

  1. Kaon Physics Review

    CERN Document Server

    Lellouch, L

    2009-01-01

    I critically review recent lattice QCD results relevant for kaon phenomenology, as well as the methods that are used to obtain them. The focus is on calculations with N_f=2 and N_f=2+1 flavors of sea quarks. Concerning methodology, the subjects covered include a discussion of how best to extrapolate and/or interpolate results to the physical quark-mass point, a scheme for assessing the extent to which a lattice QCD calculation includes the various effects required to compute a given quantity reliably and a procedure for averaging lattice results. The phenomenological topics that I review comprise leptonic and semileptonic kaon decays, as well as neutral kaon mixing and CP violation in K->\\pi\\pi decays.

  2. Measurement of CP-Violating Asymmetries In Neutral B Meson Decays Into Three Kaons

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Joshua M. [Stanford Univ., CA (United States)

    2008-12-01

    The Standard Model (SM) of particle physics successfully describes all of the observed interactions of the fundamental particles (with the exception of non-zero neutrino mass). Despite this enormous success, the SM is widely viewed as an incomplete theory. For example, the size of the asymmetry between matter and antimatter is not nearly large enough to account for the abundance of matter observed throughout the universe. It is thus believed that as-yet-unknown physical phenomena must exist that introduce new asymmetries between matter and antimatter. In this thesis, by studying decays that happen only rarely in the SM, we make measurements of asymmetries between matter and antimatter that are potentially sensitive to the existence of processes beyond the SM. At the PEP-II asymmetric-energy B Factory at SLAC, electrons and positrons are collided at the Υ(4S) resonance to create pairs of B mesons. The BABAR detector is used to measure the subsequent decay products. Using 383 million Υ(4S) → B$\\bar{B}$ decays, we study the decay B0 → K+K-K0. In the SM, this decay is dominated by loop amplitudes. Asymmetries between matter and antimatter (CP asymmetries) are extracted by measuring the time-dependence of the complex amplitudes describing the B0 and $\\bar{B}$0 decays as functions of their kinematics. The interference between decays with and without the mixing of neutral B mesons allows for the measurement of the angle βeff, which is a measure of CP violation. We also measure the direct CP asymmetry ACP. Data samples reconstructed from three K0 modes (KS0 → π+π-, KS0 → π0π0, and KL0) are fit simultaneously. They find ACP = -0.015 ± 0.077 ± 0.053 and βeff = 0.352 ± 0.076 ± 0.026 rad, corresponding to a CP violation

  3. The photon veto system for the NA62 rare kaon decay experiment

    Science.gov (United States)

    Venditti, Stefano

    2010-05-01

    Three possible solutions for a system of large-angle vetoes (LAV) have been analyzed and tested in order to choose the best option for the NA62 experiment, expected to take data in 2011/12 at CERN. The rejection power assured by the veto system, whose goal is mainly to veto photons from the K+→π+π0 and K+→π+π0π0 decays, is a key-point to collect ˜100 events of the K+→π+νν¯ decay ( BR˜10-10) with a total background (BG) of the order of 10%, thus providing a very stringent test of the Standard Model (SM) and a measurement of the Vtd element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. The details of this study and the final decision taken will be reviewed in this paper.

  4. Recent results on kaon decays by the NA48/2 experiment at CERN

    Science.gov (United States)

    Bloch-Devaux, Brigitte; Venditti, Stefano

    2016-12-01

    The NA48/2 experiment reports the first observation of the rare decay K ± → π ± π 0 e + e -, based on about 2000 candidates from 2003 data. The preliminary branching ratio in the full kinematic region is {B}(K^{± } to π ^{± }π 0e+e-)=(4.06± 0.17)\\cdot 10^{-6}. A sample of 4.687 × 106 K^{± }to π ^{± }{π 0D} events collected in 2003/4 is analyzed to search for the dark photon (A^' }) via the decay chain K ± → π ± π 0, π 0to γ A^' }, A^' }to e+e-. No signal is observed, limits in the plane mixing parameter ɛ 2 versus its mass m_{A^' }} are reported.

  5. Measurements of Charged Kaon Semileptonic Decay Branching Fractions $K^{+-} \\to \\pi^0 \\mu^{+-} \

    CERN Document Server

    Batley, J R; Arcidiacono, R; Baldini, W; Balev, S; Behler, M; Bifani, S; Biino, C; Bizzeti, A; Bloch-Devaux, B; Bocquet, G; Cabibbo, Nicola; Calvetti, M; Cartiglia, N; Ceccucci, A; Celeghini, E; Cenci, P; Cerri, C; Cheshkov, C; Chèze, J B; Clemencic, M; Collazuol, G; Costantini, F; Cotta-Ramusino, A; Coward, D; Cundy, Donald C; Dabrowski, A; Dalpiaz, P; Damiani, C; De Beer, M; Derré, J; Di Lella, Luigi; Dibon, Heinz; Doble, N; Eppard, K; Falaleev, V; Fantechi, R; Fidecaro, Maria; Fiorini, L; Fiorini, M; Fonseca-Martin, T; Frabetti, P L; Gatignon, L; Gianoli, A; Giudici, S; Gonidec, A; Goudzovski, E; Goy-Lopez, S; Holder, M; Iacopini, E; Imbergamo, E; Jeitler, Manfred; Kekelidze, V D; Khristov, P Z; Kleinknecht, K; Kozhuharov, V; Kubischta, Werner; Lamanna, G; Lazzeroni, C; Lenti, M; Litov, L; Madigozhin, D T; Maier, A; Mannelli, I; Marchetto, F; Marel, Gérard; Marinova, E; Markytan, Manfred; Marouelli, P; Martelli, F; Martini, M; Masetti, L; Mazzucato, E; Michetti, A; Mikulec, I; Molokanova, N A; Monnier, E; Moosbrugger, U; Morales-Morales, C; Munday, D J; Neuhofer, G; Norton, A; Patel, M; Pepé, M; Peters, A; Petrucci, F; Petrucci, M C; Peyaud, B; Piccini, M; Pierazzini, G M; Polenkevich, I; Potrebenikov, Yu K; Raggi, M; Renk, B; Rubin, P; Ruggiero, G; Savrié, M; Scarpa, M; Shieh, M; Slater, M W; Sozzi, M; Stoynev, S; Swallow, E; Szleper, M; Valdata-Nappi, M; Vallage, B; Velasco, M; Veltri, M; Wache, M; Wahle, H; Walker, A; Wanke, R; Widhalm, L; Winhart, A; Winston, R; Wood, M D; Wotton, S A; Zinchenko, A I; Ziolkowski, M

    2007-01-01

    Measured ratios of decay rates for $\\rkekp$, $\\rkmukp$ and $\\rkmuke$ are presented. These measurements are based on $K^\\pm$ decays collected in a dedicated run in 2003 by the NA48/2 experiment at CERN. The results obtained are $\\rkekp = 0.2496\\pm 0.0009 (stat)\\pm 0.0004 (syst)$ and $\\rkmukp = 0.1637\\pm 0.0006 (stat)\\pm 0.0003 (syst)$. Using the PDG average for the $K^\\pm \\rightarrow\\pi^\\pm \\pi^0$ normalisation mode, both values are found to be larger than the current values given by the Particle Data Book and lead to a larger magnitude of the $|V_{us}|$ CKM parameter than previously accepted. In addition, a new measured value of $\\rkmuke = 0.656\\pm 0.003(stat)\\pm 0.001(syst)$ is compared to the semi-empirical predictions based on the latest form factor measurements.

  6. Measurement of charged kaon semileptonic decay branching fraction using ISTRA+ detector

    Science.gov (United States)

    Uvarov, V. A.; Akimenko, S. A.; Bolotov, V. N.; Britvich, G. I.; Duk, V. A.; Filin, A. P.; Inyakin, A. V.; Kholodenko, S. A.; Khudyakov, A. A.; Konstantinov, A. S.; Konstantinov, V. F.; Leontiev, V. M.; Makarov, A. I.; Obraztsov, V. F.; Polyakov, V. A.; Polyarush, A. Yu.; Popov, A. V.; Romanovsky, V. I.; Stenyakin, O. V.; Tchikilev, O. G.; Yushchenko, O. P.

    2014-06-01

    The ratio of branching fractions for and K - → π-π0 decays has been measured using the ISTRA+ spectrometer. The result of our measurement is the following: Using the current PDG value for the K 2π branching fraction, this result leads to the measured K e3 branching fraction of Br( K e3) = 0.0501 ± 0.0009 and to the value of | V us | f +(0) = 0.2115 ± 0.0021.

  7. Nonleptonic kaon decays and nonperturbative QCD effects in chiral-bag model

    Energy Technology Data Exchange (ETDEWEB)

    Horvat, D.; Narancic, Z.; Tadic, D.

    1988-05-01

    The instanton induced-term, proposed by Konishi and Ranfone (1985) was introduced in the chiral-bag model based analysis of K -> 2..pi.. decays. Almost perfect fit of the experimental data was possible with the induced-term coefficient C/sub 1/ tilde approx. = 1,4. However, this conclusion, which is appreciably larger than the rough theoretical estimate (which was C/sub 1/ tilde = 0.15 m/sub s/..mu..) depends on the approximation used in the theoretical approach. (orig.HSI)

  8. Exploratory Lattice QCD Study of the Rare Kaon Decay K+→π+ν ν ¯

    Science.gov (United States)

    Bai, Ziyuan; Christ, Norman H.; Feng, Xu; Lawson, Andrew; Portelli, Antonin; Sachrajda, Christopher T.; Rbc-Ukqcd Collaboration

    2017-06-01

    We report a first, complete lattice QCD calculation of the long-distance contribution to the K+→π+ν ν ¯ decay within the standard model. This is a second-order weak process involving two four-Fermi operators that is highly sensitive to new physics and being studied by the NA62 experiment at CERN. While much of this decay comes from perturbative, short-distance physics, there is a long-distance part, perhaps as large as the planned experimental error, which involves nonperturbative phenomena. The calculation presented here, with unphysical quark masses, demonstrates that this contribution can be computed using lattice methods by overcoming three technical difficulties: (i) a short-distance divergence that results when the two weak operators approach each other, (ii) exponentially growing, unphysical terms that appear in Euclidean, second-order perturbation theory, and (iii) potentially large finite-volume effects. A follow-on calculation with physical quark masses and controlled systematic errors will be possible with the next generation of computers.

  9. Kaon Physics at KLOE

    CERN Document Server

    Ambrosino, F; Antonelli, M; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, Sergio; Bini, C; Bloise, C; Bocci, V; Bossi, F; Bowring, D; Branchini, P; Caloi, R; Campana, P; Capon, G; Capussela, T; Cera, F; Chi, S; Chiefari, G; Ciambrone, P; Conetti, S; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Dell'Agnello, S; Denig, A; Di Domenico, A; Di Donato, C; Di Falco, S; Di Micco, B; Doria, A; Dreucci, M; Fe, G; Ferrari, A; Ferrer, M L; Finocchiaro, G; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Incagli, M; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Pontecorvo, L; Primavera, M; San, P; Santovetti, E; Saracino, G; Sciascia, B; Sciubba, A; Scuri, F; Sfiligoi, I; Spadaro, T; Testa, M; Tortora, L; Valente, P; Valeriani, B; Venanzoni, G; Veneziano, Stefano; Ventura, A; Versaci, R; Xu, G; Palutan, Matteo

    2006-01-01

    The most precise determination of Vus comes from semileptonic kaon decays. We have measured with the KLOE detector at DAFNE, the Frascati phi-factory, all the experimental inputs to Vus for both neutral and charged kaons. Using our results we extract the value of Vus with about 0.9% fractional error, which is entirely dominated by the theoretical error on the knowledge of the normalization of the decay form factors, f0. A new determination of the ratio Vus/Vud is also presented, based on our precise measurement of the absolute branching ratio for the decay K+ -> mu+nu, combined with recent lattice results for the ratio f_K/f_pi. New results on CPT symmetry have also been achieved, which are based on the first measurement of the charge asymmetry for Ks -> pi e nu decay.

  10. Competition between radiative and strong force decay

    Science.gov (United States)

    Tabor, Samuel

    2017-01-01

    For nuclear states unbound to neutron decay, radiative emission is often assumed to not dominate over neutron decay mediated by the far stronger strong interaction, except for very low neutron energies and high angular momentum barriers. Recent experimental investigations of 19O and 27 Mg populated in heavy-ion fusion-evaporation reactions have revealed predominantly gamma decays from a number of states unbound to neutron decay by up to 2 MeV. In most cases the angular momentum barrier is not sufficient to inhibit neutron decay enough to allow E-M decay with widths of up to an eV or so to win. Other inhibitions to particle decay, including low spectroscopic factors, will be discussed. Supported in part by NSF Grant No. 1401574.

  11. Radiative/EW penguin decays at Belle

    CERN Document Server

    Taniguchi, Nanae

    2009-01-01

    We present recent results for radiative and electroweak penguin decays of $B$ me son at Belle. Measurements of differential branching fraction, isospin asymmetr y, $K^*$ polarization, and forward-backward asymmetry as functions of $q^2$ for $B \\to K^{(*)}ll$ decays are reported. For the results of the radiative process, we report measurements of branching fractions for inclusive $B\\to X_s \\gamma$ and the exclusive $B\\to K \\eta' \\gamma$ modes.

  12. Level Zero Trigger Processor for the ultra rare kaon decay experiment: NA62

    Science.gov (United States)

    Soldi, Dario; Chiozzi, S.; Gamberini, E.; Gianoli, A.; Mila, G.; Neri, I.; Petrucci, F.

    2017-02-01

    The NA62 experiment is designed to measure the (ultra-)rare decay K+ →π+ ν ν bar branching ratio with a precision of ∼ 10 % at the CERN Super Proton Synchrotron (SPS). The L0 Trigger Processor (L0TP) is the lowest level system of the trigger chain. It is hardware implemented using programmable logic. The architecture of the L0TP is completely new for a high energy physics experiment. It is fully digital, based on a standard gigabit ethernet communication between detectors and L0TP Board. The L0TP Board is a commercial development board, Terasic DE4, mounting an Altera Stratix IV FPGA. The primitives generated by sub-detectors are sent asynchronously using the UDP protocol to the L0TP during the entire beam spill period (about 5 seconds). The L0TP realigns in time the primitives coming from 7 different sources and manages the information of the time plus all the characteristics of the event as energy, multiplicity and position of hits in order to select good events with a comparison with preset masks. It should guarantee a maximum latency of 1 ms. The maximum input rate is 10 MHz for each sub-detector, while the design maximum output trigger rate is 1 MHz. A complete trigger-less parasitic acquisition of the primitives is possible using mirroring switches to monitor the L0 behavior. A first version of the L0TP was commissioned during the 2014 NA62 pilot run and it is used in the current data taking. A description of the trigger algorithm is here presented.

  13. Kaon fluctuations from lattice QCD

    CERN Document Server

    Noronha-Hostler, Jacquelyn; Gunther, Jana; Parotto, Paolo; Pasztor, Attila; Vazquez, Israel Portillo; Ratti, Claudia

    2016-01-01

    We show that it is possible to isolate a set of kaon fluctuations in lattice QCD. By means of the Hadron Resonance Gas (HRG) model, we calculate the actual kaon second-to-first fluctuation ratio, which receives contribution from primordial kaons and resonance decays, and show that it is very close to the one obtained for primordial kaons in the Boltzmann approximation. The latter only involves the strangeness and electric charge chemical potentials, which are functions of $T$ and $\\mu_B$ due to the experimental constraint on strangeness and electric charge, and can therefore be calculated on the lattice. This provides an unambiguous method to extract the kaon freeze-out temperature, by comparing the lattice results to the experimental values for the corresponding fluctuations.

  14. Supersymmetric Scenarios with Dominant Radiative Neutralino Decay

    CERN Document Server

    Ambrosanio, S; Ambrosanio, Sandro; Mele, Barbara

    1997-01-01

    The radiative decay of the next-to-lightest neutralino into a lightest neutralino and a photon is analyzed in the MSSM. We find that significant regions of the supersymmetric parameter space with large radiative BR's (up to about 100%) do exist. The radiative channel turns out to be enhanced when the neutralino tree-level decays are suppressed either `kinematically' or `dynamically'. In general, in the regions allowed by LEP data and not characterized by asymptotic values of the SuSy parameters, the radiative enhancement requires tan beta ~= 1 and/or M_1 ~= M_2, and negative values of relaxing the usual relation M_1=(5/3)*tan^2(th_W)*M_2, i.e. gaugino mass unification at the GUT scale. The influence of varying the stop masses and mixing angle when the radiative decay is enhanced is also considered. Some phenomenological consequences of the above picture are discussed.

  15. Study of \\chi_{bJ}(1P) Properties in the Radiative \\Upsilon(2S) Decays

    CERN Document Server

    Abdesselam, A; Adamczyk, K; Aihara, H; Said, S Al; Arinstein, K; Arita, Y; Asner, D M; Aso, T; Atmacan, H; Aulchenko, V; Aushev, T; Ayad, R; Aziz, T; Babu, V; Badhrees, I; Bahinipati, S; Bakich, A M; Bala, A; Ban, Y; Bansal, V; Barberio, E; Barrett, M; Bartel, W; Bay, A; Bedny, I; Behera, P; Belhorn, M; Belous, K; Berger, M; Besson, D; Bhardwaj, V; Bhuyan, B; Biswal, J; Bloomfield, T; Blyth, S; Bobrov, A; Bondar, A; Bonvicini, G; Bookwalter, C; Boulahouache, C; Bozek, A; Bračko, M; Breibeck, F; Brodzicka, J; Browder, T E; Waheed, E; Červenkov, D; Chang, M -C; Chang, P; Chao, Y; Chekelian, V; Chen, A; Chen, K -F; Chen, P; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, S -K; Choi, Y; Cinabro, D; Crnkovic, J; Dalseno, J; Danilov, M; Dash, N; Di Carlo, S; Dingfelder, J; Doležal, Z; Dossett, D; Drásal, Z; Drutskoy, A; Dubey, S; Dutta, D; Dutta, K; Eidelman, S; Epifanov, D; Esen, S; Farhat, H; Fast, J E; Feindt, M; Ferber, T; Frey, A; Frost, O; Fulsom, B G; Gaur, V; Gabyshev, N; Ganguly, S; Garmash, A; Getzkow, D; Gillard, R; Giordano, F; Glattauer, R; Goh, Y M; Goldenzweig, P; Golob, B; Greenwald, D; Perdekamp, M Grosse; Grygier, J; Grzymkowska, O; Guo, H; Haba, J; Hamer, P; Han, Y L; Hara, K; Hara, T; Hasegawa, Y; Hasenbusch, J; Hayasaka, K; Hayashii, H; He, X H; Heck, M; Hedges, M T; Heffernan, D; Heider, M; Heller, A; Higuchi, T; Himori, S; Hirose, S; Horiguchi, T; Hoshi, Y; Hoshina, K; Hou, W -S; Hsiung, Y B; Hsu, C -L; Huschle, M; Hyun, H J; Igarashi, Y; Iijima, T; Imamura, M; Inami, K; Inguglia, G; Ishikawa, A; Itagaki, K; Itoh, R; Iwabuchi, M; Iwasaki, M; Iwasaki, Y; Iwata, S; Jacobs, W W; Jaegle, I; Jeon, H B; Joffe, D; Jones, M; Joo, K K; Julius, T; Kakuno, H; Kang, J H; Kang, K H; Kapusta, P; Kataoka, S U; Kato, E; Kato, Y; Katrenko, P; Kawai, H; Kawasaki, T; Keck, T; Kichimi, H; Kiesling, C; Kim, B H; Kim, D Y; Kim, H J; Kim, H -J; Kim, J B; Kim, J H; Kim, K T; Kim, M J; Kim, S H; Kim, S K; Kim, Y J; Kinoshita, K; Kleinwort, C; Klucar, J; Ko, B R; Kobayashi, N; Koblitz, S; Kodyš, P; Koga, Y; Korpar, S; Kotchetkov, D; Kouzes, R T; Križan, P; Krokovny, P; Kronenbitter, B; Kuhr, T; Kulasiri, L; Kumar, R; Kumita, T; Kurihara, E; Kuroki, Y; Kuzmin, A; Kvasnička, P; Kwon, Y -J; Lai, Y -T; Lange, J S; Lee, D H; Lee, I S; Lee, S -H; Leitgab, M; Leitner, R; Levit, D; Lewis, P; Li, C H; Li, H; Li, J; Li, L; Li, X; Li, Y; Gioi, L Li; Libby, J; Limosani, A; Liu, C; Liu, Y; Liu, Z Q; Liventsev, D; Loos, A; Louvot, R; Lubej, M; Lukin, P; Luo, T; MacNaughton, J; Masuda, M; Matsuda, T; Matvienko, D; Matyja, A; McOnie, S; Mikami, Y; Miyabayashi, K; Miyachi, Y; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Mohanty, G B; Mohanty, S; Mohapatra, D; Moll, A; Moon, H K; Mori, T; Morii, T; Moser, H -G; Müller, T; Muramatsu, N; Mussa, R; Nagamine, T; Nagasaka, Y; Nakahama, Y; Nakamura, I; Nakamura, K R; Nakano, E; Nakano, H; Nakano, T; Nakao, M; Nakayama, H; Nakazawa, H; Nanut, T; Nath, K J; Natkaniec, Z; Nayak, M; Nedelkovska, E; Negishi, K; Neichi, K; Ng, C; Niebuhr, C; Niiyama, M; Nisar, N K; Nishida, S; Nishimura, K; Nitoh, O; Nozaki, T; Ogawa, A; Ogawa, S; Ohshima, T; Okuno, S; Olsen, S L; Ono, Y; Onuki, Y; Ostrowicz, W; Oswald, C; Ozaki, H; Pakhlov, P; Pakhlova, G; Pal, B; Palka, H; Panzenböck, E; Park, C -S; Park, C W; Park, H; Park, K S; Paul, S; Peak, L S; Pedlar, T K; Peng, T; Pesántez, L; Pestotnik, R; Peters, M; Petrič, M; Piilonen, L E; Poluektov, A; Prasanth, K; Prim, M; Prothmann, K; Pulvermacher, C; Purohit, M V; Rauch, J; Reisert, B; Ribežl, E; Ritter, M; Röhrken, M; Rorie, J; Rostomyan, A; Rozanska, M; Rummel, S; Ryu, S; Sahoo, H; Saito, T; Sakai, K; Sakai, Y; Sandilya, S; Santel, D; Santelj, L; Sanuki, T; Sasao, N; Sato, Y; Savinov, V; Schlüter, T; Schneider, O; Schnell, G; Schönmeier, P; Schram, M; Schwanda, C; Schwartz, A J; Schwenker, B; Seidl, R; Seino, Y; Semmler, D; Senyo, K; Seon, O; Seong, I S; Sevior, M E; Shang, L; Shapkin, M; Shebalin, V; Shen, C P; Shibata, T -A; Shibuya, H; Shinomiya, S; Shiu, J -G; Shwartz, B; Sibidanov, A; Simon, F; Singh, J B; Sinha, R; Smerkol, P; Sohn, Y -S; Sokolov, A; Soloviev, Y; Solovieva, E; Stanič, S; Starič, M; Steder, M; Strube, J F; Stypula, J; Sugihara, S; Sugiyama, A; Sumihama, M; Sumisawa, K; Sumiyoshi, T; Suzuki, K; Suzuki, K; Suzuki, S; Suzuki, S Y; Suzuki, Z; Takeichi, H; Takizawa, M; Tamponi, U; Tanaka, M; Tanaka, S; Tanida, K; Taniguchi, N; Taylor, G N; Tenchini, F; Teramoto, Y; Tikhomirov, I; Trabelsi, K; Trusov, V; Tse, Y F; Tsuboyama, T; Uchida, M; Uchida, T; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Uozumi, S; Urquijo, P; Ushiroda, Y; Usov, Y; Vahsen, S E; Van Hulse, C; Vanhoefer, P; Varner, G; Varvell, K E; Vervink, K; Vinokurova, A; Vorobyev, V; Vossen, A; Wagner, M N; Waheed, E; Wang, C H; Wang, J; Wang, M -Z; Wang, P; Wang, X L; Watanabe, M; Watanabe, Y; Wedd, R; Wehle, S; White, E; Widmann, E; Wiechczynski, J; Williams, K M; Won, E; Yabsley, B D; Yamada, S; Yamamoto, H; Yamaoka, J; Yamashita, Y; Yamauchi, M; Yashchenko, S; Ye, H; Yelton, J; Yook, Y; Yuan, C Z; Yusa, Y; Zhang, C C; Zhang, L M; Zhang, Z P; Zhao, L; Zhilich, V; Zhukova, V; Zhulanov, V; Ziegler, M; Zivko, T; Zupanc, A; Zwahlen, N; Zyukova, O

    2016-01-01

    We report a study of radiative decays of \\chi_{bJ}(1P)(J=0,1,2) mesons into 74 hadronic final states comprising charged and neutral pions, kaons, protons; out of these, 41 modes are observed with at least 5 standard deviation significance. Our measurements not only improve the previous measurements by the CLEO Collaboration but also lead to first observations in many new modes. The large sample allows us to probe the total decay width of the \\chi_{b0}(1P). In the absence of a statistically significant result, a 90% confidence-level upper limit is set on the width at \\Gamma_{total}< 2.4 MeV. Our results are based on 24.7 fb^{-1} of e+e- collision data recorded by the Belle detector at the \\Upsilon(2S) resonance, corresponding to (157.8\\pm3.6)\\times10^6 \\Upsilon(2S) decays.

  16. Study of Two-Body B Decays to Kaons and Pions Observation of $B \\to \\pi^{+}\\pi^{-}, B \\to K^{\\pm}\\pi^{0}$, and $B \\to K^{0}\\pi^{0}$ Decays

    CERN Document Server

    Cronin-Hennessy, D; Lyon, A L; Thorndike, E H; Jessop, C P; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Boulahouache, C; Bukin, K; Dambasuren, E; Karamov, S; Kopp, S E; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Csorna, S E; Danko, I; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Schrenk, S; Bonvicini, G; Cinabro, D; Perera, L P; Zhou, G J; Eigen, G; Lipeles, E; Schmidtler, M; Shapiro, A; Sun, W M; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Gronberg, J B; Hill, T S; Lange, D J; Morrison, R J; Nelson, H N; Briere, R A; Behrens, B H; Ford, W T; Gritsan, A; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lohner, M; Magerkurth, A; Meyer, T O; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Valant-Spaight, B L; Warburton, A; Avery, P; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J; Brandenburg, G; Ershov, A; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Bean, A; Besson, D; Davis, R; Kravchenko, I V; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Urheim, J; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Mahmood, A H; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Lorenc, J; Pedlar, T K; Schwarthoff, H; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A; Chen, S; Fast, J; Hinson, J W; Lee, J; Menon, N; Miller, D H; Shibata, E I; Shipsey, I P J; Pavlunin, V

    2000-01-01

    We have studied charmless hadronic decays of B mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: BR(B-> pi+ pi-) = (4.3^{+1.6}_{-1.4} \\pm 0.5) \\times 10^{-6}, BR(B-> K0 pi0) = (14.6^{+5.9+2.4}_{-5.1-3.3}) \\times 10^{-6}, and BR(B-> K+- pi0) = (11.6^{+3.0+1.4}_{-2.7-1.3}) \\times 10^{-6}. We also update our previous measurements for the decays B->K+- pi-+ and B-> K0 pi+-.

  17. Measurements of CP Violation and Neutral Kaon Charge Radius using K(L) → π+π-e+e- Decays

    Energy Technology Data Exchange (ETDEWEB)

    Golossanov, Alexander [Univ. of Virginia, Charlottesville, VA (United States)

    2005-05-01

    CP violation and K{sup 0} charge radius were measured using KL → π+π-e+e- decays. Specifically, a unique CP-violating decay-plane asymmetry was measured along with the parameters of individual contributions to the decay invariant amplitude: (1) CP-conserving magnetic dipole direct emission form factor, (2) CP-conserving K0 charge radius transition amplitude and (3) an upper limit for the CP-violating electric dipole direct emission amplitude. The measurements were obtained from the data sample accumulated by KTeV experiment at Fermilab. KTeV had two major goals: the measurement of direct CP violation parameter Re(ϵ'/ϵ) and the study of rare kaon decays. The state of the art detector was constructed, commissioned, operated and maintained by an international collaboration of scientists from fourteen institutions. The KL → π+π-e+e-L decays took place in the KTeV fiducial decay region.

  18. International Conference on Kaon Physics

    CERN Document Server

    2016-01-01

    The Conference follows former editions with similar emphasis on kaon physics. aiming at a comprehensive discussion on the latest experimental and theoretical achievements and development of new projects. TOPICS: CP and T violation CKM matrix and Flavor Mixing Rare decays Precise SM tests CPT and Quantum Mechanics Lepton universality and flavor violation Lattice gauge theory Chiral perturbation theory Physics beyond the Standard Model Future opportunities in Kaon Physics

  19. Extraction of kaon formfactors from K{sup -{yields}{mu}-{nu}{gamma}} decay at ISTRA+ setup

    Energy Technology Data Exchange (ETDEWEB)

    Duk, V.A., E-mail: Viacheslav.Duk@cern.c [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Bolotov, V.N.; Lebedev, V.A.; Khudyakov, A.A.; Makarov, A.I.; Polyarush, A.Yu.; Novikov, V.P. [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Akimenko, S.A.; Britvich, G.I.; Filin, A.P.; Inyakin, A.V.; Korolkov, I.Ya.; Leontiev, V.M.; Obraztsov, V.F.; Polyakov, V.A.; Romanovsky, V.I.; Tchikilev, O.G.; Uvarov, V.A.; Yushchenko, O.P. [Institute for High Energy Physics, Protvino (Russian Federation)

    2011-01-10

    The radiative decay K{sup -{yields}{mu}-{nu}}{sub {mu}{gamma}} has been studied at ISTRA+ setup in a new kinematic region. About 22K events of K{sup -{yields}{mu}-{nu}}{sub {mu}{gamma}} have been observed. The sign and value of F{sub V}-F{sub A} have been measured for the first time. The result is F{sub V}-F{sub A}=0.21{+-}0.04(stat){+-}0.04(syst).

  20. Measurement of $\\psip$ Radiative Decays

    OpenAIRE

    Ablikim, M.; J.Z. Bai; Ban, Y.; Collaboration, BES

    2006-01-01

    Using 14 million psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gamma ppbar, gamma 2(pi^+pi^-), gamma K_s K^-pi^++c.c., gamma K^+ K^- pi^+pi^-, gamma K^{*0} K^- pi^+ +c.c., gamma K^{*0}\\bar K^{*0}, gamma pi^+pi^- p pbar, gamma 2(K^+K^-), gamma 3(pi^+pi^-), and gamma 2(pi^+pi^-)K^+K^- with the invariant mass of hadrons below 2.9GeV/c^2. We also report branching fractions of psi(2S) decays into 2(pi^+...

  1. LHCb: Radiative Decays at LHCb

    CERN Multimedia

    Teodorescu, E

    2011-01-01

    The decay modes $B_d\\to K^*\\gamma$ and $B_s \\to \\phi \\gamma$ are promising laboratories for the search of New Physics effects, their properties being particularly sensitive to the presence of new heavy particles that may propagate virtually within the one-loop process involved in penguin diagrams. The penguin $B_s \\to \\phi \\gamma$ decay has been observed by Belle with rather poor precision, $\\mathcal{B}$($B_s \\to \\phi \\gamma$) = 57$^{+22}_{-19}$ x 10$^{-6}$, therefore, additional measurements are expected for this channel. With a data sample corresponding to an integrated luminosity of ~36 pb$^{-1}$ collected in 2010, a clear and promising signal has been observed for the $B_d\\to K^*\\gamma$. The mass resolution is dominated by the electromagnetic calorimeter energy resolution (ECAL is inter-calibrated at the ~2% level). A first hint of the $B_s \\to \\Phi \\gamma$  decay has also been observed. Given this preliminary results and the theory predictions, we expect that, with the data we will record in 2011, th...

  2. Branching Ratio Measurements Of B Meson Decays To J/psi Meson Eta Meson Kaon And Charged B Meson Decays To Neutral D Meson Charged Kaon With Neutral D Meson Decays To Positive Pion Negative Pion Neutral Pion

    CERN Document Server

    Zeng, Q

    2005-01-01

    Results are presented for the decays of B → J/ψηK and B± → DK±, respectively, with experimental data collected with BABAR detector at PEP-II, located at Stanford Linear Accelerator Center (SLAC). With 90 × 106 BB¯ events at the ϒ(4S) resonance, we obtained branching fractions of B (B± → J/ψηK ±) = [10.8 ± 2.3(stat) ± 2.4(syst)] × 10−5 and B (B0 → J/ψη K0S ) = [8.4 ± 2.6(stat) ± 2.7( syst)] × 10−5; and we set an upper limit of B [B± → X(3872) K± → J/ψηK ±] < 7.7 × 10−6 at 90% confidence level. The branching fraction of decay chain B (B± → DK ± → π+π−π 0K±) = [5.5 ± 1.0( stat) &...

  3. Radiative decay of light and heavy mesons

    Energy Technology Data Exchange (ETDEWEB)

    Barik, N. (Department of Physics, Utkal University, Bhubaneswar-751004 (India)); Dash, P.C. (Department of Physics, P. N. College, Khurda, Orissa (India))

    1994-01-01

    The [ital M]1 transition among the vector ([ital V]) and pseudoscalar ([ital P]) mesons in the light and heavy flavor sectors has been investigated in a potential model of independent quarks. Going beyond the static approximation, to add some momentum dependence due to the recoil effect in a more realistic calculation, we find an improvement in the results for the radiative decay of light flavored mesons. However, our prediction on the decay rates for the mesons ([ital D][sup *] and [ital B][sup *]) in the heavy flavor sector remains unaffected and compares well with those of other model calculations.

  4. Measurement of branching fractions and search for CP-violating charge asymmetries in charmless two-body B decays into pions and kaons.

    Science.gov (United States)

    Aubert, B; Boutigny, D; Gaillard, J M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Palano, A; Chen, G P; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Reinertsen, P L; Stugu, B; Abbott, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Clark, A R; Fan, Q; Gill, M S; Gowdy, S J; Gritsan, A; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kluth, S; Kolomensky, Y G; Kral, J F; LeClerc, C; Levi, M E; Liu, T; Lynch, G; Meyer, A B; Momayezi, M; Oddone, P J; Perazzo, A; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Bright-Thomas, P G; Harrison, T J; Hawkes, C M; Kirk, A; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Koch, H; Krug, J; Kunze, M; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Andress, J C; Barlow, N R; Bhimji, W; Chevalier, N; Clark, P J; Cottingham, W N; De Groot, N; Dyce, N; Foster, B; Mass, A; McFall, J D; Wallom, D; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Camanzi, B; Jolly, S; McKemey, A K; Tinslay, J; Blinov, V E; Bukin, A D; Bukin, D A; Buzykaev, A R; Dubrovin, M S; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Salnikov, A A; Serednyakov, S I; Skovpen, Y I; Telnov, V I; Yushkov, A N; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Ahsan, A; Arisaka, K; Buchanan, C; Chun, S; Branson, J G; MacFarlane, D B; Prell, S; Rahatlou, S; Raven, G; Sharma, V; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Richman, J D; Verkerke, W; Witherell, M; Yellin, S; Beringer, J; Dorfan, D E; Eisner, A M; Frey, A; Grillo, A A; Grothe, M; Heusch, C A; Johnson, R P; Kroeger, W; Lockman, W S; Pulliam, T; Sadrozinski, H; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Metzler, S; Oyang, J; Porter, F C; Ryd, A; Samuel, A; Weaver, M; Yang, S; Zhu, R Y; Devmal, S; Geld, T L; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Bloom, P; Fahey, S; Ford, W T; Gaede, F; Johnson, D R; Michael, A K; Nauenberg, U; Olivas, A; Park, H; Rankin, P; Roy, J; Sen, S; Smith, J G; van Hoek, W C; Wagner, D L; Blouw, J; Harton, J L; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Brandt, T; Brose, J; Colberg, T; Dahlinger, G; Dickopp, M; Dubitzky, R S; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Behr, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; Roussot, E; T'Jampens, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Muheim, F; Playfer, S; Swain, J E; Falbo, M; Bozzi, C; Dittongo, S; Folegani, M; Piemontese, L; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Xie, Y; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Fabbricatore, P; Farinon, S; Lo Vetere, M; Macri, M; Monge, M R; Musenich, R; Pallavicini, M; Parodi, R; Passaggio, S; Pastore, F C; Patrignani, C; Pia, M G; Priano, C; Robutti, E; Santroni, A; Morii, M; Bartoldus, R; Dignan, T; Hamilton, R; Mallik, U; Cochran, J; Crawley, H B; Fischer, P A; Lamsa, J; Meyer, W T; Rosenberg, E I; Benkebil, M; Grosdidier, G; Hast, C; Höcker, A; Lacker, H M; LePeltier, V; Lutz, A M; Plaszczynski, S; Schune, M H; Trincaz-Duvoid, S; Valassi, A; Wormser, G; Bionta, R M; Brigljevic, V; Fackler, O; Fujino, D; Lange, D J; Mugge, M; Shi, X; van Bibber, K; Wenaus, T J; Wright, D M; Wuest, C R; Carroll, M; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gunawardane, N J; Martin, R; Nash, J A; Sanders, P; Smith, D; Azzopardi, D E; Back, J J; Dixon, P; Harrison, P F; Potter, R J; Shorthouse, H W; Strother, P; Vidal, P B; Williams, M I; Cowan, G; George, S; Green, M G; Kurup, A; Marker, C E; McGrath, P; McMahon, T R; Ricciardi, S; Salvatore, F; Scott, I; Vaitsas, G; Brown, D; Davis, C L; Allison, J; Barlow, R J; Boyd, J T; Forti, A; Fullwood, J; Jackson, F; Lafferty, G D; Savvas, N; Simopoulos, E T; Weatherall, J H; Farbin, A; Jawahery, A; Lillard, V; Olsen, J; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Lin, C S; Moore, T B; Staengle, H; Willocq, S; Wittlin, J; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Britton, D I; Milek, M; Patel, P M; Trischuk, J; Lanni, F; Palombo, F; Bauer, J M; Booke, M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Martin, J P; Nief, J Y; Seitz, R; Taras, P; Zacek, V; Nicholson, H; Sutton, C S; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L

    2001-10-08

    We present measurements, based on a sample of approximately 23x10(6) BB pairs, of the branching fractions and a search for CP-violating charge asymmetries in charmless hadronic decays of B mesons into two-body final states of kaons and pions. We find the branching fractions B(B0-->pi(+)pi(-)) = (4.1+/-1.0+/-0.7)x10(-6), B(B0-->K+pi(-)) = (16.7+/-1.6+/-1.3)x10(-6), B(B+-->K+pi(0)) = (10.8(+2.1)(-1.9)+/-1.0)x10(-6), B(B+-->K0pi(+)) = (18.2(+3.3)(-3.0)+/-2.0)x10(-6), B(B0-->K0pi(0)) = (8.2(+3.1)(-2.7)+/-1.2)x10(-6). We also report 90% confidence level upper limits for B meson decays to the pi(+)pi(0), K+K-, and K0K+ final states. In addition, charge asymmetries have been found to be consistent with zero, where the statistical precision is in the range of +/-0.10 to +/-0.18, depending on the decay mode.

  5. The Search For The Cp-violating Emission Of An E1 Photon From The Kaon Long Decays To Positive Pion Negative Pion Gamma

    CERN Document Server

    Shields, J M

    2005-01-01

    A search for the CP-violating electric dipole (E1) direct emission contribution to the KL → π+π −γ decay is performed using data from the 1997 KTeV/E832 experiment. Because the KL → π +π−γ decay mode is massively dominated by the CP-violating inner bremsstrahlung (IB) and the CP-conserving magnetic dipole (M1) direct emission processes, previous analyses have neglected the E1 contribution. Therefore, this measurement is the first attempt to directly quantify the size of the E1 decay process. This E1 transition is one of the very few CP-violating processes that is accessible to experiment and, in principle, will produce new insights into the structure of the neutral kaon. The result of this analysis is that the E1 contribution is below the threshold of sensitivity, and therefore an upper bound of |g E1| < 0.14 (90% CL) is reported. In the process of obtaining this upper limit, high resolution measurements of fit parame...

  6. Measurement of CP asymmetries and branching fractions in two-body neutral B meson decays to charged pions and kaons with the BABAR detector

    Science.gov (United States)

    Farbin, Amir

    This dissertation presents a measurement of CP asymmetries and branching fractions for neutral B meson decays to two-body final states of charged pions and kaons. The results are obtained from a data sample of about 88 million Upsilon(4S) → BB¯ decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B factory located at the Stanford Linear Accelerator Center. A fit to kinematic, topological, and particle identification information measures the charge-averaged branching fractions B (B0 → pi+pi -) = (4.7 +/- 0.6 +/- 0.2) x 10-6 and B (B0 → K+pi -) = (17.9 +/- 0.9 +/- 0.7) x 10-6 ; the 90% confidence level upper limit B (B0 → K+ K-) b-flavor tagging information measures the CP-violating parameters for B0 → pi +pi- decays Spipi = 0.02 +/- 0.34 +/- 0.05 [-0.54, +0.58] and Cpipi = -0.30 +/- 0.25 +/- 0.04 [-0.72, +0.12].

  7. Rare Kaon Decays, KEK experiment E391 and E14 at the Japan Physics and Accelerator Research Complex (J-PARC)

    Energy Technology Data Exchange (ETDEWEB)

    Wah, Yau Wai [University of Chicago

    2012-12-06

    The goal of the J-PARC neutral kaon experiment (E14/KOTO) is to discover and measure the rate of the kaon rare decay to pi-zero and two neutrinos. This flavor changing neutral current decay proceeds through second-order weak interactions. Other, as yet undiscovered particles, which can mediate the decay could provide an enhancement (or depletion) to the branching ratio which in the Standard Model is accurately predicted within a few percent to be 2.8x10-11. The experiment is designed to observe more than 100 events at the Standard Model branching. It is a follow-up of the KEK E391a experiment and has stage-2 approval by J-PARC PAC in 2007. E14/KOTO has collaborators from Japan (Kyoto, Osaka, Yamagata, Saga), US (Arizona State, Chicago, Michigan Ann Arbor), Taiwan (National Taiwan), Korea, and Russia (Dubna). The experiment exploits the 300kW 30-50 GeV proton delivery of the J-PARC accelerator with a hermetic high acceptance detector with a fine grained Cesium Iodide (CsI) crystal calorimeter, and state of the art electronic front end and data acquisition system. With the recovery of the tsunami disaster on March 11th 2011, E14 is scheduled to start collecting data in December 2012. During the detector construction phase, Chicago focuses on the front end electronics readout of the entire detector system, particularly the CsI calorimeter. The CsI crystals together with its photomultipliers were previously used at the Fermilab KTeV experiment (E832/E799), and were loaned to E14 via this Chicago DOE support. The new readout electronics includes an innovative 10-pole pulse-shaping technique coupled with high speed digitization (14-bit 125MHz and 12-bit 500MHz). This new instrument enables us to measure both energy and timing, particularly with timing resolution better than 100 psec. Besides the cost saving by elimination of the standard time to digital converters, it is now possible to measure the momenta of the final state photons for additional background suppression

  8. Measurement of CP Asymmetries and Branching Fractions in Neutral B Meson Decays to Charged Pions and Kaons with the BABAR Detector

    Energy Technology Data Exchange (ETDEWEB)

    Farbin, A.

    2005-02-10

    This dissertation presents a measurement of CP asymmetries and branching fractions for neutral B meson decays to two-body final states of charged pions and kaons. The results are obtained from a data sample of about 88 million {Upsilon}(4S) {yields} B{bar B} decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B factory located at the Stanford Linear Accelerator Center. A fit to kinematic, topological, and particle identification information measures the charge-averaged branching fractions {Beta}(B{sup 0} {yields} {pi}{sup +}{pi}{sup -}) = (4.7 {+-} 0.6 {+-} 0.2) x 10{sup -6} and {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}) = (17.9 {+-} 0.9 {+-} 0.7) x 10{sup -6}; the 90% confidence level upper limit {Beta}(B{sup 0} {yields} K{sup +}K{sup -}) < 0.6 x 10{sup -6}; and the direct CP-violating charge asymmetry {Alpha}{sub K{pi}} = -0.102 {+-} 0.050 {+-} 0.016 [-0.188, -0.016], where the first uncertainties are statistical and the second are systematic and the ranges in square brackets indicate the 90% confidence interval. A fit which adds decay time and b-flavor tagging information measures the CP-violating parameters for B{sup 0} {yields} {pi}{sup +}{pi}{sup -} decays S{sub {pi}{pi}} = 0.02 {+-} 0.34 {+-} 0.05 [-0.54, +0.58] and C{sub {pi}{pi}} = -0.30 {+-} 0.25 {+-} 0.04 [-0.72, +0.12].

  9. Measurement of Branching Fractions and Search for CP-Violating Charge Asymmetries in Charmless Two-Body B Decays into Pions and Kaons

    CERN Document Server

    Aubert, Bernard; Gaillard, Jean-Marc; Hicheur, A; Karyotakis, Yu; Lees, J P; Robbe, P; Tisserand, V; Palano, A; Chen, G P; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Reinertsen, P L; Stugu, B; Abbott, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Clark, A R; Fan, Q; Gill, M S; Gowdy, S J; Gritsan, A; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kluth, S; Kolomensky, Yu G; Kral, J F; Le Clerc, C; Levi, M E; Liu, T; Lynch, G; Meyer, A B; Momayezi, M; Oddone, P J; Perazzo, A; Pripstein, M; Roe, N A; Romosan, A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Bright-Thomas, P G; Harrison, T J; Hawkes, C M; Kirk, A; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Koch, H; Krug, J; Kunze, M; Lewandowski, B; Peters, K; Schmücker, H; Steinke, M; Andress, J C; Barlow, N R; Bhimji, W; Chevalier, N; Clark, P J; Cottingham, W N; De Groot, N; Dyce, N; Foster, B; Mass, A; McFall, J D; Wallom, D; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Camanzi, B; Jolly, S; McKemey, A K; Tinslay, J; Blinov, V E; Bukin, A D; Bukin, D A; Buzykaev, A R; Dubrovin, M S; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Salnikov, A A; Serednyakov, S I; Skovpen, Yu I; Telnov, V I; Yushkov, A N; Lankford, A J; Mandelkern, M A; McMahon, S; Stoker, D P; Ahsan, A; Arisaka, K; Buchanan, C; Chun, S; Branson, J G; MacFarlane, D B; Prell, S; Rahatlou, S; Raven, G; Sharma, V; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Richman, J D; Verkerke, W; Witherell, M; Yellin, S; Beringer, J; Dorfan, D E; Eisner, A M; Frey, A; Grillo, A A; Grothe, M; Heusch, C A; Johnson, R P; Kröger, W; Lockman, W S; Pulliam, T; Sadrozinski, H F W; Schalk, T L; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Metzler, S; Oyang, J; Porter, F C; Ryd, A; Samuel, A; Weaver, M; Yang, S; Zhu, R Y; Devmal, S C; Geld, T L; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Bloom, P; Fahey, S; Ford, W T; Gaede, F; Johnson, D R; Michael, A K; Nauenberg, U; Olivas, A; Park, H; Rankin, P; Roy, J; Sen, S; Smith, J G; Van Hoek, W C; Wagner, D L; Blouw, J; Harton, J L; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Brandt, T; Brose, J; Colberg, T; Dahlinger, G; Dickopp, M; Dubitzky, R S; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, Klaus R; Schwierz, R; Spaan, B; Wilden, L; Behr, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; Roussot, E; T'Jampens, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Muheim, F; Playfer, S; Swain, J E; Falbo, M; Bozzi, C; Dittongo, S; Folegani, M; Piemontese, L; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Xie, Y; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Fabbricatore, P; Farinon, S; Lo Vetere, M; Macri, M; Monge, M R; Musenich, R; Pallavicini, M; Parodi, R; Passaggio, S; Pastore, F C; Patrignani, C; Pia, M G; Priano, C; Robutti, E; Santroni, A; Morii, M; Bartoldus, R; Dignan, T; Hamilton, R; Mallik, U; Cochran, J; Crawley, H B; Fischer, P A; Lamsa, J; Meyer, W T; Rosenberg, E I; Benkebil, M; Grosdidier, G; Hast, C; Höcker, A; Lacker, H M; Le Peltier, V; Lutz, A M; Plaszczynski, S; Schune, M H; Trincaz-Duvoid, S; Valassi, Andrea; Wormser, G; Bionta, R M; Brigljevic, V; Fackler, O; Fujino, D; Lange, D J; Mugge, M; Shi, X; Van Bibber, K; Wenaus, T J; Wright, D M; Wuest, C R; Carroll, M; Fry, J R; Gabathuler, Erwin; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gunawardane, N J W; Martin, R; Nash, J A; Sanders, P; Smith, D; Azzopardi, D E; Back, J J; Dixon, P; Harrison, P F; Potter, R J L; Shorthouse, H W; Strother, P; Vidal, P B; Williams, M I; Cowan, G; George, S; Green, M G; Kurup, A; Marker, C E; McGrath, P; McMahon, T R; Ricciardi, S; Salvatore, F; Scott, I; Vaitsas, G; Brown, D; Davis, C L; Allison, J; Barlow, R J; Boyd, J T; Forti, A C; Fullwood, J; Jackson, F; Lafferty, G D; Savvas, N; Simopoulos, E T; Weatherall, J H; Farbin, A; Jawahery, A; Lillard, V; Olsen, J; Roberts, D A; Schieck, J; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Lin, C S; Moore, T B; Stängle, H; Willocq, S; Wittlin, J; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Britton, D I; Milek, M; Patel, P M; Trischuk, J; Lanni, F; Palombo, F; Bauer, J M; Booke, M; Cremaldi, L M; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Martin, J P; Nief, J Y; Seitz, R; Taras, P; Zacek, V; Nicholson, H; Sutton, C S; Cartaro, C; Cavallo, N; De, G; Nardo; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R G; Gabriel, T A; Handler, T; Brau, J E; Frey, R; Iwasaki, M; Sinev, N B; Strom, D; Colecchia, F; Dal Corso, F; Dorigo, A; Galeazzi, F; Margoni, M; Michelon, G; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Torassa, E; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; Le Diberder, F R; Leruste, P; Lory, J; Roos, L; Stark, J; Versille, S; Manfredi, P F; Re, V; Speziali, V; Frank, E D; Gladney, L; Guo, Q H; Panetta, J H; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Martínez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Simi, G; Triggiani, G; Walsh, J; Haire, M J; Judd, D; Paick, K; Turnbull, L; Wagoner, D E; Albert, J; Bula, C; Lü, C; McDonald, K T; Miftakov, V; Schaffner, S F; Smith, A J S; Tumanov, A; Varnes, E W; Cavoto, G; Del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Fratini, K; Lamanna, E; Leonardi, E; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Serra, M; Voena, C; Christ, S; Waldi, R; Jacques, P F; Kalelkar, M; Plano, R J; Adye, T; Franek, B J; Geddes, N I; Gopal, Gian P; Xella, S M; Aleksan, Roy; De Domenico, G; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; London, G W; Mayer, B; Serfass, B; Vasseur, G; Yéche, C; Zito, M; Copty, N K; Purohit, M V; Singh, H; Yumiceva, F X; Adam, I; Anthony, P L; Aston, D; Baird, K G; Bloom, Elliott D; Boyarski, A M; Bulos, F; Calderini, G; Convery, M R; Coupal, D P; Coward, D H; Dorfan, J; Doser, Michael; Dunwoodie, W M; Field, R C; Glanzman, T; Godfrey, G L; Grosso, P; Himel, Thomas M; Huffer, M E; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Lüth, V; Lynch, H L; Manzin, G; Marsiske, H; Menke, S; Messner, R; Moffeit, K C; Mount, R; Müller, D R; O'Grady, C P; Petrak, S; Quinn, Helen R; Ratcliff, B N; Robertson, S H; Rochester, L S; Roodman, A; Schietinger, T; Schindler, R H; Schwiening, J; Serbo, V V; Snyder, A; Soha, A; Spanier, S M; Stahl, A; Stelzer, J; Su, D; Sullivan, M K; Talby, M; Tanaka, H A; Trunov, A G; Vavra, J; Wagner, S R; Weinstein, A J; Wisniewski, W J; Young, C C; Burchat, Patricia R; Cheng, C H; Kirkby, D; Meyer, T I; Roat, C; Henderson, R; Bugg, W; Cohn, H; Hart, E; Weidemann, A W; Benninger, T; Izen, J M; Kitayama, I; Lou, X C; Turcotte, M; Bianchi, F; Bóna, M; Di Girolamo, B; Gamba, D; Smol, A V; Zanin, D; Bosisio, L; Della Ricca, G; Lanceri, L; Pompili, A; Poropat, P; Prest, M; Vallazza, E; Vuagnin, G; Panvini, R S; Brown, C M; De Silva, A; Kowalewski, R V; Roney, J M; Band, H R; Charles, E; Dasu, S; Di Lodovico, F; Elmer, P; Hu, H; Johnson, J R; Liu, R; Nielsen, J; Orejudos, W; Pan, Y; Prepost, R; Scott, I J; Sekula, S J; Von Wimmersperg-Töller, J H; Wu Sau Lan; Yu, Z; Zobernig, H; Kordich, T M B; Neal, H; Ollaboration, BABAR C

    2001-01-01

    We present measurements of the branching fractions and a search for CP-violating charge asymmetries in charmless hadronic decays of B mesons into two-body final states of kaons and pions. The results are based on a data sample of approximately 23 million BB(bar) pairs collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. We find the following branching fractions: BF(B0-->pi+pi-)= (4.1+/-1.0+/-0.7) x 10^{-6}, BF(B0-->K+pi-)=(16.7+/-1.6+/-1.3) x 10^{-6}, BF(B+-->K+pi0)=(10.8^{ +2.1}_{-1.9}+/-1.0) x 10^{-6}, BF(B+-->K0pi+)=(18.2^{+3.3}_{-3.0}+/-2. 0) x 10^{-6}, BF(B0-->K0pi0)=(8.2^{+3.1}_{-2.7}+/-1.2) x 10^{-6}. We also report the 90% confidence level upper limits BF(B0-->K+K-) pi+pi0) anti-K0K+) < 2.4 x 10^{-6}. In addition, charge asymmetries have been measured and found to be consistent with zero, where the statistical precision is in the range of +/-0.10 to +/-0.18, depending on the decay mode.

  10. Kaon Flavour Physics Strikes Back

    CERN Document Server

    Buras, Andrzej J

    2016-01-01

    In this short presentation I emphasize the increased importance of kaon flavour physics in the search for new physics (NP) that we should witness in the rest of this decade and in the next decade. The main actors will be the branching ratios for the rare decays $K^+\\rightarrow\\pi^+\

  11. Radiative corrections in K --> 3 pi decays

    CERN Document Server

    Bissegger, M; Gasser, J; Kubis, B; Rusetsky, A

    2008-01-01

    We investigate radiative corrections to K --> 3 pi decays. In particular, we extend the non-relativistic framework developed recently to include real and virtual photons and show that, in a well-defined power counting scheme, the results reproduce corrections obtained in the relativistic calculation. Real photons are included exactly, beyond the soft-photon approximation, and we compare the result with the latter. The singularities generated by pionium near threshold are investigated, and a region is identified where standard perturbation theory in the fine structure constant alpha may be applied. We expect that the formulae provided allow one to extract S-wave pi pi scattering lengths from the cusp effect in these decays with high precision.

  12. Rare radiative leptonic B-decays

    CERN Document Server

    Kozachuk, Anastasiia; Nikitin, Nikolai

    2016-01-01

    We obtain predictions for $B_{(s)}\\to e^+e^-\\gamma$ and $B_{(s)}\\to \\mu^+\\mu^-\\gamma$ decays. All the contributions containing long-distance QCD effects are calculated in the framework of relativistic quark model. The contributions of the light vector-meson resonances related to the virtual photon emission from valence quarks of the $B$-meson are included. The highest branching ratios for the radiative leptonic B-decays are ${\\cal B}(\\bar B^0_s\\to e^+e^-\\gamma)=18.8\\times10^{-9}$ and ${\\cal B}(B^0_s\\to \\mu^+\\mu^-\\gamma)=12.2\\times10^{-9}$. We also give the distribution of the foward-backward asymmetry.

  13. Form Factors in radiative pion decay

    CERN Document Server

    Mateu, V

    2007-01-01

    We perform an analysis of the form factors that rule the structure-dependent amplitude in the radiative pion decay. The resonance contributions to pion -> e nu_e gamma decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic properties of the three-point Green functions VVP and VAP, and by demanding the smoothing of the form factors at high transfer of momentum. A comparison between theoretical and experimental determinations of the form factors is also carried out. We also consider and evaluate the role played by a non-standard tensor form factor. We conclude that, at present and due to the hadronic incertitudes, the search for New Physics in this process is not feasible.

  14. SEARCH FOR THE RARE KAON DECAY K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}}

    Energy Technology Data Exchange (ETDEWEB)

    BHUYAN,B.

    2003-05-03

    This thesis describes the search for the rare decay K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} in the pion momentum region 140 MeV/c {le} P{sub {pi}{sup +}} {le} 195 MeV/c. This is a Flavor Changing Neutral Current (FCNC) decay which is forbidden to the first order in the Standard Model (SM) by the GIM mechanism. However, this decay mode is allowed in the second order by two Z-Penguin and one box diagram and is expected to have a branching ratio of (0.72 {+-} 0.21) x 10{sup -10}. This decay mode is sensitive to the coupling of top to down quark and therefore a measurement of the branching ratio for this decay mode provides a measurement of the Cabibbo-Kobayashi-Maskawa matrix element V{sub td}. The recent observation of two events in the pion momentum region 211 MeV/c {le} P{sup {pi}{sup +}} {le} 229 MeV/c estimates a branching ratio of 1.57{sub -0.82}{sup +1.75} x 10{sup -10} for the same decay mode. We have extended the search for this decay to the lower pion momentum region. Data collected by the Experiment E787 at Brookhaven National Laboratory during the 1996 and 1997 run were analyzed in this thesis.

  15. Potential Models for Radiative Rare B Decays

    CERN Document Server

    Ahmad, S

    2002-01-01

    We compute the branching ratios for the radiative rare decays of B into K-Meson states and compare them to the experimentally determined branching ratio for inclusive decay b -> s gamma using non relativistic quark model, and form factor definitions consistent with HQET covariant trace formalism. Such calculations necessarily involve a potential model. In order to test the sensitivity of calculations to potential models we have used three different potentials, namely linear potential, screening confining potential and heavy quark potential as it stands in QCD.We find the branching ratios relative to the inclusive b ->s gamma decay to be (16.07\\pm 5.2)% for B -> K^* (892)gamma and (7.25\\pm 3.2)% for B -> K_2^* (1430)gamma for linear potential. In the case of the screening confining potential these values are (19.75\\pm 5.3)% and (4.74\\pm 1.2)% while those for the heavy quark potential are (11.18\\pm 4.6)% and (5.09\\pm 2.7)% respectively. All these values are consistent with the corresponding present CLEO experim...

  16. Dalitz Plot Analysis Of Neutral B-meson Decays To Charged Kaon, Charged Pion, And Neutral Pion Final States

    CERN Document Server

    Yu, Z

    2005-01-01

    This thesis describes a Dalitz plot analysis of B0 → K+π−π 0 decays. The data sample comprises 213 million &Ugr;(4 S) → BB¯ decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center in California (SLAGC). Preliminary results are presented for measurements of the inclusive branching fraction, quasi-two-body fractions and CP-violating charge asymmetries for intermediate states including K*(892)+π − and ρ(770)−K +. Observations of B0 decays to the Kπ S-wave intermediate states, K*0 (1430)+π− and K*0 (1430)0π0, are reported. Evidence of the decay B0 → K*(892) 0π0 is seen. We set tipper limits at 90% confidence level on branching fractions of the nonresonant and other less significant intermediate states.

  17. Exclusive rare radiative decays of B mesons

    Energy Technology Data Exchange (ETDEWEB)

    Barik, N. [Physics Department, Utkal University, Bhubaneswar-751004 (India); Kar, S.; Dash, P.C. [Physics Department, Prananath College, Khurda-752057 (India)

    1998-01-01

    The exclusive rare radiative B decays are studied in the relativistic independent quark model based on the confining potential in the scalar-vector harmonic form. The relevant form factors as well as the branching ratios for the processes B{sup 0}{r_arrow}K{sup {asterisk}0}{gamma} and B{sup {plus_minus}}{r_arrow}K{sup {asterisk}{plus_minus}}{gamma} have been estimated in reasonable agreement with the available experimental data. The result compares well with several other model predictions. The calculation has been extended to the CKM-favored process B{sub s}{r_arrow}{phi}{gamma} and CKM-suppressed processes B{sub u,d}{r_arrow}{rho}{gamma} and B{sub s}{r_arrow}K{sup {asterisk}}{gamma}. {copyright} {ital 1997} {ital The American Physical Society}

  18. Inclusive Radiative $J/\\psi$ Decays

    CERN Document Server

    Besson, D; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; Méndez, H; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hunt, J M; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Ledoux, J; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R

    2008-01-01

    Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon momentum spectrum in the decay J/psi->gamma+gluon+gluon, via the 'tagged' process: e+e- -> psi(2S); psi(2S)->J/psi pi+pi-; J/psi->photon + X. Including contributions from two-body radiative decay processes, we find the ratio of the inclusive direct photon branching fraction to that of the dominant three-gluon branching fraction to be R=0.137+/-0.001+/-0.016+/-0.004, where the errors shown are statistical, systematic, and the model-dependent uncertainty related to the extrapolation to zero photon energy. The shape of the scaled photon energy spectrum in J/psi->gg gamma is observed to be very similar to that of Upsilon(1S)->gg gamma. The R value obtained is roughly consistent with that expected by a simple quark-charge scaling of the value determined at the Upsilon(1S), but somewhat higher than the value expected from the running of the strong coupling constant.

  19. Search for CP-violation in the decay of neutral kaons to $\\pi^{+}\\pi^{- }\\pi^{0}$

    CERN Document Server

    Adler, R; Angelopoulos, Angelos; Apostolakis, Alcibiades J; Aslanides, Elie; Backenstoss, Gerhard; Bee, C P; Behnke, O; Benelli, A; Bennet, J; Bertin, V; Bienlein, J K; Blanc, F; Bloch, P; Bula, C; Carlson, P J; Carroll, M; Carvalho, J; Cawley, E; Charalambous, S; Chardalas, M; Chardin, G; Chertok, M B; Cody, A; Danielsson, M; Dedoussis, S; Dejardin, M; Derré, J; Dodgson, M; Duclos, J; Ealet, A; Eckart, B; Eleftheriadis, C; Evangelou, I; Faravel, L; Fassnacht, P; Faure, J L; Felder, C; Ferreira-Marques, R; Fetscher, W; Fidecaro, Maria; Filipcic, A; Francis, D; Fry, J; Fuglesang, C; Gabathuler, Erwin; Gamet, R; Garreta, D; Geralis, T; Gerber, H J; Go, A; Gumplinger, P; Guyot, C; Harrison, P F; Haselden, A; Hayman, P J; Henry-Coüannier, F; Heyes, W G; Hollander, R W; Hubert, E; Jansson, K; Johner, H U; Jon-And, K; Kettle, P R; Kochowski, Claude; Kokkas, P; Kreuger, R; Lawry, T; Le Gac, R; Leimgruber, F; Liolios, A; Machado, E; Maley, P; Mandic, I; Manthos, N; Marel, Gérard; Mikuz, M; Miller, J; Montanet, François; Nakada, Tatsuya; Onofre, A; Pagels, B; Papadopoulos, I M; Pavlopoulos, P; Pelucchi, F; Pinto da Cunha, J; Policarpo, Armando; Polivka, G; Postma, H; Rickenbach, R; Roberts, B L; Rozaki, E; Ruf, T; Sacks, L; Sakelliou, L; Sanders, P; Santoni, C; Sarigiannis, K; Schäfer, M; Schaller, L A; Schietinger, T; Schopper, A; Schune, P; Soares, A; Tauscher, Ludwig; Thibault, C; Touchard, F; Touramanis, C; Triantis, F A; Tröster, D A; Van Beveren, E; van Eijk, C W E; Varner, G S; Vlachos, S; Weber, P; Wigger, O; Witzig, C; Wolter, M; Yéche, C; Zavrtanik, D; Zimmerman, D; And, Jon; da Cunha, J Pinto

    1996-01-01

    The time-dependent rate asymmetry of initial \\ko and \\kob decaying into \\threepi was measured in order to reveal the CP-violating amplitude of the \\ks \\rightarrow \\threepi decay. For the real and the imaginary parts of \\eta_{+-0}, we find \\mbox{\\rm Re}(\\eta_{+-0}) = (6 \\pm 13_{\\mbox{\\rm stat.}}\\pm 1_{\\mbox{\\rm syst.}})\\times 10^{-3} and \\mbox{\\rm Im}(\\eta_{+-0}) = (-2 \\pm 18_{\\mbox{\\rm stat.}}\\pm 3_{\\mbox{\\rm syst.}})\\times 10^{-3} %\\mbox{\\rm Im}(\\eta_{+-0}) = (-2 \\pm 18_{\\mbox{\\rm stat.}}\\pm 2_{\\mbox{\\rm syst.}})\\times 10^{-3} which correspond to |\\eta_{+-0}|<0.037 with 90\\% CL.

  20. Global effective-field-theory analysis of new-physics effects in (semi)leptonic kaon decays

    Energy Technology Data Exchange (ETDEWEB)

    González-Alonso, Martín [IPN de Lyon/CNRS, Universite Lyon 1,Villeurbanne (France); Camalich, Jorge Martin [CERN, Theoretical Physics Department,Geneva (Switzerland)

    2016-12-14

    We analyze the decays K→πℓν and P→ℓν (P=K,π, ℓ=e, μ) using a low-energy Effective-Field-Theory approach to parametrize New Physics and study the complementarity with baryon β decays. We then provide a road map for a global analysis of the experimental data, with all the Wilson coefficients simultaneously, and perform a fit leading to numerical bounds for them and for V{sub us}. A prominent result of our analysis is a reinterpretation of the well-known V{sub ud}−V{sub us} diagram as a strong constraint on new physics. Finally, we reinterpret our bounds in terms of the SU(2){sub L}× U(1){sub Y}-invariant operators, provide bounds to the corresponding Wilson coefficients at the TeV scale and compare our results with collider searches at the LHC.

  1. Measurement of time-dependent CP violation asymmetries in neutral B meson decays to phi meson neutral kaon(short)

    Science.gov (United States)

    Chuvikov, Aleksey

    We present measurements of time-dependent CP asymmetry parameters in B0 → φK s transitions. We reconstruct one neutral B meson decaying into a CP eigenstate and use the inclusive information of the remaining particles to determine the avor of the accompanying meson at its decay time. Using a data sample of 492 fb-1 collected at the Upsilon(4S) resonance with the Belle detector at the asymmetric KEKB accelerator, we reconstruct 202 B0 → φ Ks decay candidates with an estimated signal purity of 81.2% after vertexing, flavor tagging and other good vertex selection. From an unbinned maximum likelihood fit to the proper time interval distribution we obtain S=0.55+/-0.31statist ical+/-0.06systematic A=0.18+/- 0.20statistical+/-0.0 5systematic The A term shows the absence of direct CP violation and the S term is consistent with the current world average of sin 2φ 1 as predicted in the Standard Model, where φ1 is one of the angles of the Unitarity Triangle corresponding to the Cabibbo-Kobayashi-Maskawa matrix.

  2. Radiative decays of negative parity heavy baryons in QCD

    CERN Document Server

    Agamaliev, A K; Savcı, M

    2016-01-01

    The transition form factors responsible for the radiative $\\Sigma_Q \\to \\Lambda_Q \\gamma$ and $\\Xi_Q^\\prime \\to \\Xi \\gamma$ decays of the negative parity baryons are examined within light cone QCD sum rules. The decay widths of the radiative transitions are calculated using the obtained results of the form factors.

  3. J/psi and UPSILON radiative and hadronic decays

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, E.D.

    1987-07-01

    The search for gluonium at the J/psi and UPSILON is discussed, as well as the search for exotics at the UPSILON. Reactions discussed include radiative and hadronic decays of the J/psi and the search for radiative decays of the UPSILON. Future perspectives are also briefly considered. 45 refs., 27 figs. (LEW)

  4. J/psi and UPSILON radiative and hadronic decays

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, E.D.

    1987-07-01

    The search for gluonium at the J/psi and UPSILON is discussed, as well as the search for exotics at the UPSILON. Reactions discussed include radiative and hadronic decays of the J/psi and the search for radiative decays of the UPSILON. Future perspectives are also briefly considered. 45 refs., 27 figs. (LEW)

  5. Study of CP Violation in Dalitz-Plot Analyses of B-Meson Decays to Three Kaons

    Energy Technology Data Exchange (ETDEWEB)

    Lindquist, Brian [Stanford Univ., CA (United States)

    2012-02-01

    The Standard Model (SM) explains CP violation in terms of the CKM matrix. The BABAR experiment was designed mainly to test the CKM model in B decays. B decays that proceed through b → s loop diagrams, of which B {yields} KKK decays are an example, are sensitive to new physics effects that could lead to deviations from the CKM predictions for CP violation. We present studies of CP violation in the decays B+ → K+K-K+, B+ → KS0KS0K+, and B0 → K+K-KS0, using a Dalitz plot amplitude analysis. These studies are based on approximately 470 million B$\\bar{B}$ decays collected by BABAR at the PEP-II collider at SLAC. We perform measurements of time-dependent CP violation in B0 → K+K-KS0, including B0 → ΦKS0. We measure a CP-violating phase βeff (ΦKS0) = 0.36 ± 0.11 ± 0.04 rad., in agreement with the SM. This is the world's most precise measurement of this quantity. We also measure direct CP asymmetries in all three decay modes, including the direct CP asymmetry ACP (ΦK+) = (12.8 ± 4.4 ± 1.3)%, which is 2.8 sigma away from zero. This measurement is in tension with the SM, which predicts an asymmetry of a few percent. We also study the resonant and nonresonant features in the B → KKK Dalitz plots. We find that the hypothetical scalar fX(1500) resonance, introduced by prior analyses to explain an unknown peak in the mKK spectrum, cannot adequately describe the data. We conclude instead that the fX(1500) can be explained as the sum of the f0(1500), f'2(1525), and f0(1710) resonances, removing the need for the hypothetical fX(1500). We also find that an exponential

  6. Measurement of the charged kaon lifetime with the KLOE detector

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bossi, F; Branchini, P; Caloi, R; Campana, P; Capon, G; Capussela, T; Ceradini, F; Chi, S; Chiefari, G; Ciambrone, P; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Sibidanov, A; Spadaro, T; Testa, M; Tortora, L; Valente, P; Venanzoni, G; Versaci, R; Xu, G

    2008-01-01

    We have measured the charged kaon lifetime using a sample of 15 \\times 10^6 tagged kaon decays. Charged kaons were produced in pairs at the DA\\PhiNE \\phi-factory, e^+e^- \\to \\phi \\to K^+ K^-. The decay of a K^+ was tagged by the production of a K^- and viceversa. The lifetime was obtained, for both charges, from independent measurements of the decay time and decay lenght distributions. From fits to the four distributions we find \\tau = (12.347\\pm0.030) ns.

  7. Exploratory Lattice QCD Study of the Rare Kaon Decay K^{+}→π^{+}νν[over ¯].

    Science.gov (United States)

    Bai, Ziyuan; Christ, Norman H; Feng, Xu; Lawson, Andrew; Portelli, Antonin; Sachrajda, Christopher T

    2017-06-23

    We report a first, complete lattice QCD calculation of the long-distance contribution to the K^{+}→π^{+}νν[over ¯] decay within the standard model. This is a second-order weak process involving two four-Fermi operators that is highly sensitive to new physics and being studied by the NA62 experiment at CERN. While much of this decay comes from perturbative, short-distance physics, there is a long-distance part, perhaps as large as the planned experimental error, which involves nonperturbative phenomena. The calculation presented here, with unphysical quark masses, demonstrates that this contribution can be computed using lattice methods by overcoming three technical difficulties: (i) a short-distance divergence that results when the two weak operators approach each other, (ii) exponentially growing, unphysical terms that appear in Euclidean, second-order perturbation theory, and (iii) potentially large finite-volume effects. A follow-on calculation with physical quark masses and controlled systematic errors will be possible with the next generation of computers.

  8. Radiative Decays of the B Meson

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Hirohisa A

    2003-09-23

    The radiative decays of the B meson to the final states K *(892){gamma} and {rho}(770){gamma} proceed through virtual effective flavor-changing neutral current processes which are sensitive to contributions from high mass scales from within the Standard Model of particle interactions and from possible new physics. In the context of the Standard Model, these transitions are of interest in probing the weak interaction behavior of the top quark. In particular, the ratio of branching fractions for the two processes can be used to extract the ratio of Cabibbo-Kobayashi-Maskawa matrix elements |V{sub td}/V{sub ts}|. Potential new physics contributions in these virtual transitions may induce new sources of direct CP violation and enhancement or suppression of the rate of these processes. The B {yields} K*{gamma} is a manifestation of the b {yields} s{gamma} radiative transition. This process has been previously observed by the CLEO collaboration and its branching fraction measured. While the theoretical prediction for the inclusive rate of b {yields} s{gamma} transitions is more robust than that of the exclusive B {yields} K*{gamma}, the prospects for precise measurements of {Beta}[B {yields} K*{gamma}] and direct CP violation in this channel has attracted considerable attention. The analysis described here represents an improved measurement of the B {yields} K*{gamma} branching factions and a more sensitive search for direct CP violation. In 22.7 x 10{sup 6} B{bar B} events collected by the BABAR detector in 1999-2000, we measure: {Beta}[B{sup 0} {yields} K*{sup 0}{gamma}] = 4.23 {+-} 0.40(stat.) {+-} 0.22(syst.) x 10{sup -5} and {Beta}[B{sup +} {yields} K*{sup +}{gamma}] = 3.83 {+-} 0.62(stat.) {+-} 0.22(syst.) x 10{sup -5}. We find no evidence for direct CP violation in the decays and constrain -0.170 < A{sub CP} < 0.082 at 90% Confidence Level. The B {yields} {rho}{gamma} proceeds through the analogous b {yields} d{gamma} radiative transition. As such, its rate is

  9. A determination of the CP violation parameter $\\eta_{+-}$ from the decay of strangeness-tagged neutral kaons

    CERN Document Server

    Apostolakis, Alcibiades J; Backenstoss, Gerhard; Bargassa, P; Behnke, O; Benelli, A; Bertin, V; Blanc, F; Bloch, P; Carlson, P J; Carroll, M; Cawley, E; Chertok, M B; Danielsson, M; Dejardin, M; Derré, J; Ealet, A; Eleftheriadis, C; Fetscher, W; Fidecaro, Maria; Filipcic, A; Francis, D; Fry, J; Gabathuler, Erwin; Gamet, R; Gerber, H J; Go, A; Haselden, A; Hayman, P J; Henry-Coüannier, F; Hollander, R W; Jon-And, K; Kettle, P R; Kokkas, P; Kreuger, R; Le Gac, R; Leimgruber, F; Mandic, I; Manthos, N; Marel, Gérard; Mikuz, M; Miller, J; Montanet, François; Müller, A; Nakada, Tatsuya; Pagels, B; Papadopoulos, I M; Pavlopoulos, P; Polivka, G; Rickenbach, R; Roberts, B L; Ruf, T; Sakelliou, L; Schäfer, M; Schaller, L A; Schietinger, T; Schopper, A; Tauscher, Ludwig; Thibault, C; Touchard, F; Touramanis, C; van Eijk, C W E; Vlachos, S; Weber, P; Wigger, O; Wolter, M; Yéche, C; Zavrtanik, D; Zimmerman, D

    1999-01-01

    We report a measurement of the CP violation parameter $\\eta$ from the time-dependent asymmetry between the decay rates of initially tagged \\kn\\ and \\knb . The results are based on the complete data sample collected by the CPLEAR collaboration. With $\\dm = (530.1 \\pm 1.4) \\times 10^{7}\\hbar s^{-1}$ and $\\ts = (89.32 \\pm 0.08)$ ps, the values obtained are $\\mita = (2.264 \\pm 0.023_\\mathrm{{stat}} \\pm 0.026_\\mathrm{{syst}} \\pm 0.007_{\\ts}) \\times 10^{-3}$ and $\\fas = 43.19^{\\circ} \\pm 0.53^{\\circ}_\\mathrm{{st at}} \\pm 0.28^{\\circ}_\\mathrm{{syst}} \\pm 0.42^{\\circ}_{\\dm}$.

  10. Study of Branching Ratio And Polarization Fraction in Neutral B Meson Decays to Negative Rho Meson Positive Kaon Resonance

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Baosen; /Wisconsin U., Madison

    2006-03-07

    We present the preliminary results on the search for B{sup 0} {yields} {rho}{sup -}K*{sup +}. The data sample comprises 122.7 million B{bar B} pairs in the e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance collected during 1999-2003 with the BABAR detector at the PEP-II asymmetric-energy collider at Stanford Linear Accelerator Center (SLAC). We obtain an upper limit of the branching ratio at 90% confidence level as {Beta}(B{sup 0} {yields} {rho}{sup -}K*{sup +}) < 17.2 x 10{sup -6}. The fitted result on the polarization fraction shows no evidence that the decay is longitudinally dominated as predicted by various theoretical models.

  11. T violation in radiative β decay and electric dipole moments

    Energy Technology Data Exchange (ETDEWEB)

    Dekens, W.; Vos, K.K., E-mail: k.k.vos@rug.nl

    2015-12-17

    In radiative β decay, T violation can be studied through a spin-independent T-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of T-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the T-odd BSM physics in radiative β decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent T-odd correlation in radiative β decay.

  12. T violation in radiative β decay and electric dipole moments

    Directory of Open Access Journals (Sweden)

    W. Dekens

    2015-12-01

    Full Text Available In radiative β decay, T violation can be studied through a spin-independent T-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM sources of T-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs. As a consequence, the manifestations of the T-odd BSM physics in radiative β decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent T-odd correlation in radiative β decay.

  13. T violation in radiative β decay and electric dipole moments

    Science.gov (United States)

    Dekens, W.; Vos, K. K.

    2015-12-01

    In radiative β decay, T violation can be studied through a spin-independent T-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of T-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the T-odd BSM physics in radiative β decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent T-odd correlation in radiative β decay.

  14. Measurement of CP Asymmetries and Branching Fractions in Charmless Two-Body B-Meson Decays to Pions and Kaons

    Energy Technology Data Exchange (ETDEWEB)

    Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Palano, A.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; /British Columbia U.; Khan, A.; /Brunel U.; Blinov, V.E.; /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2012-06-18

    We present improved measurements of CP-violation parameters in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, and B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and of the branching fractions for B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0} and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. The results are obtained with the full data set collected at the {Upsilon}(4S) resonance by the BABAR experiment at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory, corresponding to 467 {+-} 5 million B{bar B} pairs. We find the CP-violation parameter values and branching fractions S{sub {pi}{sup +}{pi}{sup -}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{sup +}{pi}{sup -}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sup -}{pi}{sup +}} = -0.107 {+-} 0.016{sub -0.004}{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K0{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where in each case, the first uncertainties are statistical and the second are systematic. We observe CP violation with a significance of 6.7 standard deviations for B{sup 0} {yields} {pi}{sup +}{pi}{sup -} and 6.1 standard deviations for B{sup 0} {yields} K{sup +}{pi}{sup -}, including systematic uncertainties. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relations among the B {yields} {pi}{pi} rates and asymmetries. Considering only the solution preferred by the Standard Model, we find {alpha} to be in the range [71{sup o}, 109{sup o}] at the 68% confidence level.

  15. New physics patterns in ɛ'/ ɛ and ɛ K with implications for rare kaon decays and ∆ M K

    Science.gov (United States)

    Buras, Andrzej J.

    2016-04-01

    The Standard Model (SM) prediction for the ratio ɛ'/ ɛ appears to be significantly below the experimental data. Also ɛ K in the SM tends to be below the data. Any new physics (NP) removing these anomalies will first of all have impact on flavour observables in the K meson system, in particular on rare decays {K}+to {π}+ν overline{ν} , {K}_Lto {π}^0ν overline{ν} , K L → μ + μ - and K L → π 0 ℓ + ℓ - and Δ M K . Restricting the operators contributing to ɛ'/ ɛ to the SM ones and to the corresponding primed operators, NP contributions to ɛ'/ ɛ are quite generally dominated either by QCD penguin (QCDP) operators Q 6( Q 6 ' ) or electroweak penguin (EWP) operators Q 8( Q 8 ' ) with rather different implications for other flavour observables. Our presentation includes general models with tree-level Z and Z' flavour violating exchanges for which we summarize known results and add several new ones. We also briefly discuss few specific models. The correlations of ɛ'/ɛ with other flavour observables listed above allow to differentiate between models in which ɛ'/ ɛ can be enhanced. Various DNA-tables are helpful in this respect. We find that simultaneous enhancements of ɛ'/ ɛ, ɛ K , B({K}_Lto {π}^0ν overline{ν}) and B({K}+to {π}+ν overline{ν}) in Z scenarios are only possible in the presence of both left-handed and right-handed flavour-violating couplings. In Z' scenarios this is not required but the size of NP effects and the correlation between B({K}_Lto {π}^0ν overline{ν}) and B({K}+to {π}+ν overline{ν}) depends strongly on whether QCDP or EWP dominate NP contributions to ɛ'/ ɛ. In the QCDP case possible enhancements of both branching ratios are much larger than for EWP scenario and take place only on the branch parallel to the Grossman-Nir bound, which is in the case of EWP dominance only possible in the absence of NP in ɛ K .We point out that QCDP and EWP scenarios of NP in ɛ'/ ɛ can also be uniquely distinguished by the

  16. Studies of radiative penguin B decays at BaBar

    Indian Academy of Sciences (India)

    John M LoSecco; BaBar Collaboration

    2004-03-01

    We summarize results on a number of observations of penguin dominated radiative decays of the meson. Such decays are forbidden at tree level and proceed via electroweak loops. As such they may be sensitive to physics beyond the standard model. The observations have been made at the BaBar experiment at PEP-II, the asymmetric factory at SLAC.

  17. Studies of Radiative Penguin B Decays at BABAR

    CERN Document Server

    Hamel de Monchenault, G

    2003-01-01

    We summarize results on a number of observations of penguin dominated radiative decays of the B meson. Such decays are forbidden at tree level and proceed via electroweak loops. As such they may be sensitive to physics beyond the standard model. The observations have been made at the BaBar experiment at PEPII, the asymmetric B factory at SLAC.

  18. A measurement of the branching ration of the neutral pion Dalitz decay using kaon(long) going to 3 neutral pion decays from KTeV

    Science.gov (United States)

    Abouzaid, Erin E.

    2007-12-01

    We present a measurement of B(pi0 → e+e- g )/B(pi0 → gg ) using data taken in 1999 by the E832 KTeV experiment at Fermilab. The pi0s were produced by KL decays in flight that are fully reconstructed. We find 63,693 K L → 3pi0 → gggg e+e- g decays in KTeV data (an increase of a factor of ˜ 20 in event statistics over previous experiments), and normalize to KL → 3pi0 → 6 g , to extract Bp0 →e+e-g,me+e ->15MeV/c2 /Bp0→gg =3.920+/-0.016+/-0.036 x10-3, where the first error is statistical and the second is systematic. Using the Mikaelian and Smith prediction for the e +e- mass spectrum as implemented in the KTeV Monte Carlo to correct to the full e+ e- mass range yields Bp0 →e+e-g /Bp0→gg =1.1559+/-0.0046+/-0.0107 %. This result is consistent with previous measurements and with theoretical predictions, and the uncertainty is a factor of three smaller than any previous measurement.

  19. The time-like electromagnetic form factors of proton and charged kaon at high energies

    Science.gov (United States)

    Anulli, Fabio

    2016-05-01

    The Initial State Radiation method in the BABAR experiment has been used to measure the time-like electromagnetic form factors at the momentum transfer from 9 to 42 (GeV/c)2 for proton and from 7 to 56 (GeV/c)2 for charged kaon. The obtained data show the tendency to approach the QCD asymptotic prediction for kaons and space-like form factor values for proton. The BABAR data have been used together with data from other experiments, to perform a model-independent determination of the relative phases between the single-photon and the three-gluon amplitudes in ψ → KK ¯ decays. The values of the branching fractions measured in the reaction e+e- → K+ K- are shifted due to interference of resonant and nonresonant amplitudes. We have determined the absolute values of the shifts to be 5% for J/ψ and 15% for ψ(2S) decays.

  20. An electroweak enigma: Hyperon radiative decays

    Energy Technology Data Exchange (ETDEWEB)

    Vorobyov, A., (spokesperson); /St. Petersburg, INP; Jastrzembski, E.; Lach, J.; Marriner, J.; /Fermilab; Golovtsov, V.; Krivshich, A.; Schegelsky, V.; Smirnov, N.; Terentiev, N.K.; Uvarov, L.; /St. Petersburg, INP; McCliment, E.; Newsom, C.; Norbeck, E.; /Iowa U.; Cooper, P.S.; /Yale U.

    1985-04-03

    The main thrust of this experiment will be to measure the asymmetry parameter for the electroweak decay {Sigma}{sup +} {yields} p{gamma} and verify its branching ratio. As a secondary goal they will measure, or set new upper limits for, the branching ratio of the electroweak decay {Xi}{sup -} {yields} {Sigma}{sup -}{gamma}. Since the {Xi}{sup -} are expected to be polarized, information on the asymmetry parameter may also be available.

  1. Kaons in nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Heiselberg, H. [NORDITA, Copenhagen (Denmark)

    1998-06-01

    The kaon energy in a nuclear medium and its dependence on kaon-nucleon and nucleon-nucleon correlations is discussed. The transition from the Lenz potential at low densities to the Hartree potential at high densities can be calculated analytically by making a Wigner-Seitz cell approximation and employing a square well potential. As the Hartree potential is less attractive than the Lenz one, kaon condensation inside cores of neutron stars appears to be less likely than previously estimated. (orig.)

  2. Meson decay studies with the KLOE detector at DA{phi}NE

    Energy Technology Data Exchange (ETDEWEB)

    Branchini, P. [Sezione INFN di Roma 3 Universita ' Roma 3' , Via Della Vasca Navale 84, Rome (Italy); Aloisio, A.; Ambrosino, F.; Antonelli, A.; Antonelli, M.; Bacci, C.; Barva, M.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Caloi, R.; Campana, P.; Capon, G.; Capussela, T.; Carboni, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; De Lucia, E.; De Santis, A.; De Simone, P.; De Zorzi, G.; Dell' Agnello, S.; Denig, A.; Di Domenico, A.; Di Donato, C.; Di Falco, S.; Di Micco, B.; Doria, A.; Dreucci, M.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franzini, P.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Gorini, E.; Graziani, E.; Incagli, M.; Kluge, W.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Leone, D.; Lu, F.; Martemianov, M.; Martini, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nguyen, F.; Palutan, M.; Pasqualucci, E.; Passalacqua, L.; Passeri, A.; Patera, V.; Perfetto, F.; Petrolo, E.; Pontecorvo, L.; Primavera, M.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Sibidanov, A.; Spadaro, T.; Spiriti, E.; Testa, M.; Tortora, L.; Valente, P.; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Ventura, A.; Versaci, R.; Villella, I.; Xu, G

    2005-04-18

    The KLOE experiment has been collecting data since april 1999 at the DA{phi}NE collider in Frascati. A statistics of about 0.45 fb-1 has been analyzed. The latest results concerning the study of the {phi} radiative decays and of the kaon decays are illustrated in this paper.

  3. The Revival of Kaon Flavour Physics

    CERN Document Server

    Buras, Andrzej J

    2016-01-01

    After years of silence we should witness in the rest of this decade and in the next decade the revival of kaon flavour physics. This is not only because of the crucial measurements of the branching ratios for the rare decays $K^+\\to\\pi^+\

  4. Sterile neutrinos facing kaon physics experiments

    Science.gov (United States)

    Abada, A.; Bečirević, D.; Sumensari, O.; Weiland, C.; Funchal, R. Zukanovich

    2017-04-01

    We discuss weak kaon decays in a scenario in which the Standard Model is extended by massive sterile fermions. After revisiting the analytical expressions for leptonic and semileptonic decays we derive the expressions for decay rates with two neutrinos in the final state. By using a simple effective model with only one sterile neutrino, compatible with all current experimental bounds and general theoretical constraints, we conduct a thorough numerical analysis which reveals that the impact of the presence of massive sterile neutrinos on kaon weak decays is very small, less than 1% on decay rates. The only exception is B (KL→ν ν ) , which can go up to O (10-10), thus possibly within the reach of the KOTO, NA62 and SHIP experiments. Plans have also been proposed to search for this decay at the NA64 experiment. In other words, if all the future measurements of weak kaon decays turn out to be compatible with the Standard Model predictions, this will not rule out the existence of massive light sterile neutrinos with non-negligible active-sterile mixing. Instead, for a sterile neutrino of mass below mK, one might obtain a huge enhancement of B (KL→ν ν ), otherwise negligibly small in the Standard Model.

  5. Developement of a same-side kaon tagging algorithm of B^0_s decays for measuring delta m_s at CDF II

    Energy Technology Data Exchange (ETDEWEB)

    Menzemer, Stephanie; /Heidelberg U.

    2006-06-01

    The authors developed a Same-Side Kaon Tagging algorithm to determine the production flavor of B{sub s}{sup 0} mesons. Until the B{sub s}{sup 0} mixing frequency is clearly observed the performance of the Same-Side Kaon Tagging algorithm can not be measured on data but has to be determined on Monte Carlo simulation. Data and Monte Carlo agreement has been evaluated for both the B{sub s}{sup 0} and the high statistics B{sup +} and B{sup 0} modes. Extensive systematic studies were performed to quantify potential discrepancies between data and Monte Carlo. The final optimized tagging algorithm exploits the particle identification capability of the CDF II detector. it achieves a tagging performance of {epsilon}D{sup 2} = 4.0{sub -1.2}{sup +0.9} on the B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +} sample. The Same-Side Kaon Tagging algorithm presented here has been applied to the ongoing B{sub s}{sup 0} mixing analysis, and has provided a factor of 3-4 increase in the effective statistical size of the sample. This improvement results in the first direct measurement of the B{sub s}{sup 0} mixing frequency.

  6. Radiative Decay of Proton Colliding with Rb at Low Energies

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yu; QU Yi-Zhi; LIU Chun-Hua; LIU Xiao-Ju

    2011-01-01

    The radiative decay and radiative charge transfer cross sections for H++Rb(5s) collisions are calculated by using the optical potential approach, the semiclassical and the fully quantum-mechanical methods, respectively, for the energy range 10-6-10eV. The radiative association cross sections are obtained by the cross section differences between the radiative decay and radiative charge transfer processes. The relevant molecular data are calculated from the multi-reference single- and double-excitation configuration interaction approach. The emission spectra at resonant and non-resonant energies are analyzed, then the isolated sharp and broad resonances can be identified by their rotational and vibration quantum numbers.

  7. psi(2S) Radiative Decay Measurements

    CERN Document Server

    Ablikim, M; Bai, Y; Ban, Y; Cai, X; Chen, H F; Chen, H S; Chen, H X; Chen, J C; Jin Chen; Chen, X D; Chen, Y B; Chu, Y P; Dai, Y S; Deng, Z Y; Du, S X; Fang, J; Fu, C D; Gao, C S; Gao, Y N; Gu, S D; Gu, Y T; Guo, Y N; Guoa, Z J; Harris, F A; He, K L; He, M; Heng, Y K; Hou, J; Hu, H M; Hu, T; Huangb, G S; Huang, X T; Huang, Y P; Ji, X B; Jiang, X S; Jiao, J B; Jin, D P; Jin, S; Lai, Y F; Li, H B; Li, J; Li, R Y; Li, W D; Li, W G; Li, X L; Li, X N; Li, X Q; Liang, Y F; Liaoc, H B; Liu, B J; Liu, C X; Fang, Liu; Feng, Liu; Liud, H H; Liu, H M; Liue, J B; Liu, J P; Liu, H B; Liu, J; Liu, Q; Liu, R G; Liu, S; Liu, Z A; Lu, F; Lu, G R; Lu, J G; Lundborgf, A; Luo, C L; Ma, F C; Ma, H L; Mag, L L; Ma, Q M; Malik, M Q A; Mao, Z P; Mo, X H; Nie, J; Olsen, S L; Ping, R G; Qi, N D; Qin, H; Qiu, J F; Rong, G; Ruan, X D; Shan, L Y; Shang, L; Shen, C P; Shen, D L; Shen, X Y; Sheng, H Y; Sun, H S; Sun, S S; Sun, Y Z; Sun, Z J; Tang, X; Tian, J P; Tong, G L; Varner, G S; Wan, X; Wang, L; Wang, L L; Wang, L S; Wang, P; Wang, P L; Wangh, W F; Wang, Y F; Wang, Z; Wang, Z Y; Wei, C L; Wei, D H; Weng, Y; Wiedner, U; Wu, N; Xia, X M; Xie, X X; Xu, G F; Xu, X P; Xu, Y; Yan, M L; Yang, H X; Yang, M; Yang, Y X; Ye, M H; Ye, Y X; Yu, C X; Yu, G W; Yuan, C Z; Yuan, Y; Zangi, S L; Zeng, Y; Zhang, B X; Zhang, B Y; Zhang, C C; Zhang, D H; Zhang, H Q; Zhang, H Y; Zhang, J W; Zhang, J Y; Zhang, X Y; Zhang, Y Y; Zhang, Z X; Zhang, Z P; Zhao, D X; Zhao, J W; Zhao, M G; Zhao, P P; Zhao, Z G; Zheng, H Q; Zheng, J P; Zheng, Z P; Zhong, B; Zhou, L; Zhu, K J; Zhu, Q M; Zhu, X W; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhu, Z L; Zhuang, B A; Zou, B S

    2008-01-01

    Using a sample of 14 million $\\psip$ events collected with the BESII detector, branching fractions or upper limits on the branching fractions of $\\psip$ decays into $\\gamma\\ppb$, $\\gamma 2(\\pip\\pim)$, $\\gamma \\kskp$, $\\gamma \\kap\\kam\\pip\\pim$, $\\gamma\\kstarz\\kam\\pip+c.c.$, $\\gamma \\kstarz \\kstarzb$, $\\gamma\\pip\\pim\\ppb$, $\\gamma2(\\kap\\kam)$, $\\gamma3(\\pip\\pim)$ and $\\gamma2(\\pip\\pim)\\kap\\kam$ with hadron invariant mass less than 2.9$\\gev/c^2$ are reported. We also report branching fractions of $\\psip$ decays into $\\gamma\\ppb\\piz$, $\\ppb\\piz\\piz$, $2(\\pip\\pim)\\piz$, $\\omega\\pp$, $\\omega f_2(1270)$, $b_1^\\pm\\pi^\\mp$, $\\piz\\kskp$, $K^\\pm\\rho^\\mp\\ks$, $\\piz2(\\pip\\pim)\\kap\\kam$ and $\\gamma\\piz2(\\pip\\pim)\\kap\\kam$.

  8. Constraints on new physics from radiative $B$ decays

    CERN Document Server

    Paul, Ayan

    2016-01-01

    A new phase for the measurements of radiative decay modes in $b \\to s$ transitions has started with new measurements of exclusive modes by LHCb and with Belle-II showing distinctive promises in both inclusive and exclusive channels. After critically reviewing the hadronic uncertainties in exclusive radiative decays, we analyze the impact of recent measurements of the branching ratio and mass-eigenstate rate asymmetry in $B_s\\to\\phi\\gamma$ and of the angular distribution of $B\\to K^*e^+e^-$ at low $q^2$ on new physics in the $b\\to s\\gamma$ transition.

  9. CP violation in the radiative dileptonic B-meson decays

    NARCIS (Netherlands)

    Erkol, G; Turan, G

    2002-01-01

    We investigate the CP violating asymmetry, the forward-backward asymmetry and the CP violating asymmetry in the forward-backward asymmetry for the radiative dileptonic B-meson decays B-d --> gammal(+)l(-) for the f = e, mu, tau channels. It is observed that these asymmetries are quite sizable and B-

  10. Radiative decays of mesons in the NJL model

    CERN Document Server

    Epele, L N; Dumm, D G; Grunfeld, A G

    2001-01-01

    We revisit the theoretical predictions for anomalous radiative decays of pseudoscalar and vector mesons. Our analysis is performed in the framework of the Nambu-Jona-Lasinio model, introducing adequate parameters to account for the breakdown of chiral symmetry. The results are comparable with those obtained in previous approaches.

  11. Weak Kaon Production off the Nucleon

    CERN Document Server

    Alam, M Rafi; Athar, M Sajjad; Vacas, M J Vicente

    2010-01-01

    The weak kaon production off the nucleon induced by neutrinos is studied at the low and intermediate energies of interest for some ongoing and future neutrino oscillation experiments. This process is also potentially important for the analysis of proton decay experiments. We develop a microscopical model based on the SU(3) chiral Lagrangians. The basic parameters of the model are fpi, the pion decay constant, Cabibbo's angle, the proton and neutron magnetic moments and the axial vector coupling constants for the baryons octet, D and F, that are obtained from the analysis of the semileptonic decays of neutron and hyperons. The studied mechanisms are the main source of kaon production for neutrino energies up to 1.2 to 1.5 GeV for the various channels and the cross sections are large enough to be amenable to be measured by experiments such as Minerva and T2K.

  12. Decay rate of the second radiation belt.

    Science.gov (United States)

    Badhwar, G D; Robbins, D E

    1996-01-01

    Variations in the Earth's trapped (Van Allen) belts produced by solar flare particle events are not well understood. Few observations of increases in particle populations have been reported. This is particularly true for effects in low Earth orbit, where manned spaceflights are conducted. This paper reports the existence of a second proton belt and it's subsequent decay as measured by a tissue-equivalent proportional counter and a particle spectrometer on five Space Shuttle flights covering an eighteen-month period. The creation of this second belt is attributed to the injection of particles from a solar particle event which occurred at 2246 UT, March 22, 1991. Comparisons with observations onboard the Russian Mir space station and other unmanned satellites are made. Shuttle measurements and data from other spacecraft are used to determine that the e-folding time of the peak of the second proton belt. It was ten months. Proton populations in the second belt returned to values of quiescent times within eighteen months. The increase in absorbed dose attributed to protons in the second belt was approximately 20%. Passive dosimeter measurements were in good agreement with this value.

  13. The possible Bπ molecular state and its radiative decay

    Energy Technology Data Exchange (ETDEWEB)

    Ke, Hong-Wei; Gao, Lei [Tianjin University, School of Science, Tianjin (China); Li, Xue-Qian [Nankai University, School of Physics, Tianjin (China)

    2017-05-15

    Recently, several exotic bosons have been confirmed as multi-quark states. However, there are violent disputes about their inner structures, namely if they are molecular states or tetraquarks, or even mixtures of the two structures. It would be interesting to search experimentally for non-strange four-quark states with open charm or bottom which are lighter than Λ{sub c} or Λ{sub b}. Reasonable arguments indicate that they are good candidates of pure molecular states Dπ or Bπ because pions are the lightest boson. Both Bπ and Dπ bound states do not decay via the strong interaction. The Bπ molecule may decay into B* by radiating a photon, whereas the Dπ molecule can only decay via weak interaction. In this paper we explore the mass spectra of the Bπ molecular states by solving the corresponding instantaneous B-S equation. Then the rate of radiative decay vertical stroke (3)/(2), (1)/(2) right angle → B*γ is calculated and our numerical results indicate that the processes can be measured by the future experiment. We also briefly discuss the Dπ case. Due to the constraint of the final state phase space it can only decay via weak interaction. (orig.)

  14. Non-radiative and radiative decays in nanogap emitting devices

    CERN Document Server

    Faggiani, Remi; Lalanne, Philippe

    2015-01-01

    By placing a quantum emitter in the mouths of nanogaps consisting of two metal nanoparticles nearly into contact, significant increases in emission rate are obtained. This mechanism is central in the design of modern plasmonic nanoantennas. However, due to the lack of general knowledge on the balance between the different decay rates in nanogaps (emission, quenching, and metal absorption), nanoantenna design is performed in a rather haphazard fashion and relies on repeated numerical calculations; general intuitive design recipes do not presently exist. With accurate and simple closed-form expressions for the quenching rate and the decay rate into gap plasmons, we provide a comprehensive analysis of nanogap light emitting devices in the limit of small gap thickness. We disclose that the total spontaneous emission rate of quantum emitters in nanometer-thin gaps can largely overcome quenching, for specifically selected metallic and insulator materials, regardless of the gap size. Furthermore, to help further des...

  15. Isospin violation in pion-kaon scattering

    CERN Document Server

    Kubis, B; Kubis, Bastian; Mei{\\ss}ner, Ulf-G.

    2002-01-01

    We consider strong and electromagnetic isospin violation in near-threshold pion-kaon scattering. At tree level, such effects are small for all physical channels. We work out the complete one-loop corrections to the process pi^- K^+ -> pi^0 K^0. They come out rather small. We also show that the corresponding radiative cross section is highly suppressed at threshold.

  16. Studies of phi meson radiative decays with KLOE

    Energy Technology Data Exchange (ETDEWEB)

    Aloisio, A.; Ambrosino, F.; Antonelli, A.; Antonelli, M.; Bacci, C.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Caloi, R.; Campana, P.; Capon, G.; Carboni, G.; Casarsa, M.; Casavola, V.; Cataldi, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; De Lucia, E.; De Robertis, G.; De Simone, P.; De Zorzi, G.; Dell' Agnello, S.; Denig, A.; Di Domenico, A.; Di Donato, C.; Di Falco, S.; Doria, A.; Dreucci, M.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franceschi, A.; Franzini, P.; Gatt, C.; Gauzzi, P.; Giovannella, S.; Gorini, E.; Grancagnolo, F.; Graziani, E.; Han, S.W.; Incagli, M.; Ingrosso, L.; Kluge, W.; Kuo, C.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Leone, D.; Lu, F.; Martemianov, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nedosekin, A.; Nguyen, F.; Palutan, M.; Pasqualucci, E.; Passalacqua, L.; Passeri, A.; Patera, V.; Petrolo, E.; Pontecorvo, L.; Primavera, M.; Ruggieri, F.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Spadaro, T.; Spiriti, E.; Tong, G.L.; Tortora, L.; Valente, E.; Valente, P.; Valeriani, B.; Vernanzoni, G.; Veneziano, S.; Ventura, A.; Xu, G.; Yu, G.W

    2003-04-01

    A sample of 5.3 x 10{sup 7}phi mesons, produced at the Frascati phi-factory DAPHINE, has been used by the KLOE Collaboration to study the phi radiative decays. The decays phi {yields} {eta}{pi}{sup 0}{gamma} and phi {yields} {pi}{sup o}{pi}{sup o}{gamma} have been exploited to study the scalar mesons a{sub o}(980) and f{sub o}(980). Furthermore a new determination of the {eta} - {eta}' mixing angle has been obtained from the measurement of the ratio of the decay rates of phi {yields} {eta}'{gamma} to phi {yields} {eta}{gamma} to phi {yields} {eta}{gamma}.

  17. Limits to the radiative decay of the axion

    Science.gov (United States)

    Ressell, M. Ted

    1991-01-01

    An axion with a mass greater than 1 eV should be detectable through its decay into two photons. The astrophysical and cosmological limits which define a small window of allowed axion mass above 3 eV are discussed. A firm upper bound to the axion's mass of M(sub a) less than or equal to 8 eV is derived by considering the effect of decaying axions upon the diffuse extragalactic background radiation and the brightness of the night sky due to axions in the halo of the Milky Way galaxy. The intergalactic light of clusters of galaxies is shown to be an ideal place to search for an emission line arising from the radiative decay of axions. An unsuccessful search for this emission line in three clusters of galaxies is then detailed. Limits to the presence of any intracluster line emission are derived with the result that axions with masses between 3 and 8 eV are excluded by the data, effectively closing this window of axion mass, unless a severe cancellation of axionic decay amplitudes occurs. The intracluster flux limits are then used to constrain the amplitude of any such model dependence.

  18. Search for the Radiative Decay B --> phi gamma

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Karyotakis, Yu; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Graugès-Pous, E; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schröder, T; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Zhang, L; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De, R; Sangro; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Biasini, M; Covarelli, R; Pioppi, M; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, Erwin; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Roos, L; Therin, G; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Simi, G; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Polci, F; Safai-Tehrani, F; Voena, C; Christ, S; Schröder, H; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Abe, T; Allen, M; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Claus, R; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dingfelder, J C; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Soha, A; Stelzer, J; Strube, J; Su, D; Sullivan, M K; Thompson, J; Vavra, J; Wagner, S R; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Martínez-Vidal, F; Panvini, R S; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Mohanty, G B; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihályi, A; Pan, Y; Prepost, R; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2003-01-01

    We perform a search for the exclusive radiative decay B0 --> phi gamma, which is dominated by b d annihilation, in a sample of 124 million BB events collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring at SLAC. No significant signal is seen. We set an upper limit on the branching fraction BR(B0 --> phi gamma < 8.5x10-7) at the 90% confidence level.

  19. Radiative Decays of Low-Lying Excited-State Hyperons

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Simon [Rice Univ., Houston, TX (United States)

    2000-05-01

    The quark wave-functions of the lower-lying excited-state hyperons Lambda(1405), Sigma(1385), and Lambda(1520) are not well understood. For example, the Lambda(1405) may not be a regular three-quark state but a $\\bar{K}$N molecule. Several competing models have been proposed, but none have been convincingly eliminated. Measuring radiative decays provides a means of discriminating between the models. The radiative branching of ratios are predicted to be small (~1%), but the radiative widths vary by factors of 2-10 from model to model. The existing experimental data is sparse and inconsistent; moreover, the radiative decay of the Sigma(1385) has never been observed before (except for one event). These lower-lying excited state hypersons were produced in a tagged photon-beam experiment in the CLAS detector at TJNAF in the reaction gamma p → K+ Y* for photon energies from threshold to 2.4 GeV. The radiative branching ration for the Sigma0(1385) relative to the Sigma0(1385) → Lambda pi0 channel was measured to be 0.021 ± 0.008$+0.004\\atop{-0.007}$, corresponding to a partial width of 640 ± 270$+130\\atop{-220}$ keV.

  20. T-odd correlations in radiative K_l3^+ decays and Chiral Perturbation Theory

    CERN Document Server

    Müller, E H; Meißner, Ulf G; Kubis, Bastian; Müller, Eike H; Mei{\\ss}ner, Ulf-G.

    2006-01-01

    The charged kaon decay channel K_l3gamma^+ allows for studies of direct CP violation, possibly due to non-standard mechanisms, with the help of T-odd correlation variables. In order to be able to extract a CP-violating signal from experiment, it is necessary to understand all possible Standard Model phases that also produce T-odd asymmetries. We complement earlier studies by considering strong interaction phases in hadronic structure functions that appear at higher orders in Chiral Perturbation Theory, and compare our findings to other potential sources of asymmetries.

  1. A search for narrow states in radiative upsilon decays

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, S.T.

    1986-12-01

    A search for new states produced in radiative UPSILON(1S) decays is accomplished by observing the inclusive photon energy spectrum. A narrow resonance in the energy spectrum indicates the existence of a new state X produced by the process UPSILON ..-->.. ..gamma..X. The analysis is based on approximately 0.44 x 10/sup 6/ UPSILON(1S) events produced at the DORIS II e/sup +/e/sup -/ storage ring. These data were collected with the Crystal Ball detector between April 1983 and May 1986. This analysis finds no evidence for a new state, so upper limits on the branching ratio BR(UPSILON ..-->.. ..gamma..X) are derived, assuming the state X decays primarily to high-multiplicity hadronic final states. In particular, if the state X were a minimal Higgs particle, its primary decay mode would be to the heaviest fermion-antifermion pair energetically available. For the radiative UPSILON(1S) decays studied here, the heavy fermions would be c anti c or s anti s quark states, over most of the relevant Higgs' mass range. The resulting upper limit for BR(UPSILON(1S) ..-->.. ..gamma..X) is highly energy dependent but for X mass between 1.5 GeV and 8.0 GeV, the 90% confidence level upper limit is better than 8.0 x 10/sup -4/. For a Higgs' mass near 5.0 GeV, the upper limit is about 2.0 x 10/sup -4/ which is approximately equal to the lowest order calculation for the Wilczek mechanism. The Wilczek calculation with QCD radiative corrections predict branching ratios below the limits set here for all Higgs' masses.

  2. International Meeting on Physics at KAON

    CERN Document Server

    Gill, David; Speth, Josef

    1990-01-01

    "Physics at KAON", an international meeting jointly organized by the KFA Jillich and TRI­ UMF, was held in the Physikzentrum Bad Honnef from June 7 through June 9, 1989. This was one of a series of meetings - the first one in Europe - in which plans for the medium energy physics laboratory KAON were presented and some aspects of the physics at this new facility were discussed. The meeting focussed mainly on the topics of hadron spectroscopy, J{ -meson scattering, strangeness in nuclei, and rare decays. Also presented were some of the research programs at SATURNE and COSY which may well lead to KAON physics in the future. These proceed­ ings include articles which summarize our current experimental and theoretical knowledge in the various areas, as well as papers which describe lines of research feasible with KAON. The large number of participants - limited, in fact, by the capacity of the Physikzentrum - clearly demonstrates the great interest of the European physics community in the research avenue...

  3. Factorization for radiative heavy quarkonium decays into scalar Glueball

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ruilin [INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology,Department of Physics and Astronomy, Shanghai Jiao Tong University,Dongchuan RD 800, Shanghai 200240 (China); State Key Laboratory of Theoretical Physics,Institute of Theoretical Physics, Chinese Academy of Sciences,Zhongguancun E. St. 55, Beijing 100190 (China); CAS Center for Excellence in Particle Physics,Institute of High Energy Physics, Chinese Academy of Sciences,Yuquan RD 19B, Beijing 100049 (China)

    2015-09-24

    We establish the factorization formula for scalar Glueball production through radiative decays of vector states of heavy quarkonia, e.g. J/ψ, ψ(2S) and Υ(nS), where the Glueball mass is much less than the parent heavy quarkonium mass. The factorization is demonstrated explicitly at one-loop level through the next-to-leading order (NLO) corrections to the hard kernel, the non-relativistic QCD (NRQCD) long-distance matrix elements (LDMEs) of the heavy quarkonium, and the light-cone distribution amplitude (LCDA) of scalar Glueball. The factorization provides a comprehensive theoretical approach to investigate Glueball production in the radiative decays of vector states of heavy quarkonia and determine the physic nature of Glueball. We discuss the scale evolution equation of LCDA for scalar Glueball. In the end, we extract the value of the decay constant of Scalar Glueball from Lattice QCD calculation and analyze the mixing effect among f{sub 0}(1370), f{sub 0}(1500) and f{sub 0}(1710).

  4. Radiative leptonic Bc decay in the relativistic independent quark model

    Science.gov (United States)

    Barik, N.; Naimuddin, Sk.; Dash, P. C.; Kar, Susmita

    2008-12-01

    The radiative leptonic decay Bc-→μ-ν¯μγ is analyzed in its leading order in a relativistic independent quark model based on a confining potential in an equally mixed scalar-vector harmonic form. The branching ratio for this decay in the vanishing lepton mass limit is obtained as Br(Bc→μνμγ)=6.83×10-5, which includes the contributions of the internal bremsstrahlung and structure-dependent diagrams at the level of the quark constituents. The contributions of the bremsstrahlung and the structure-dependent diagrams, as well as their additive interference parts, are compared and found to be of the same order of magnitude. Finally, the predicted photon energy spectrum is observed here to be almost symmetrical about the peak value of the photon energy at Ẽγ≃(MBc)/(4), which may be quite accessible experimentally at LHC in near future.

  5. Radiative Leptonic Decay of Ds and D Mesons

    Science.gov (United States)

    Barik, N.; Naimuddin, Sk.; Dash, P. C.

    The radiative leptonic decays Ds → μνμγ and D → μνμγ are investigated at the tree level within the relativistic independent quark model based on the confining potential in the scalar-vector harmonic form. The branching ratios for these decays in the vanishing lepton mass limit are obtained as ℬr(Ds → μνμγ) = 4.94×10-4 and ℬr(D → μνμγ) = 3.34×10-5, which includes the contributions of the internal bremsstrahlung and structure dependent diagrams at the level of the quark constituents. Finally, the photon energy spectra as predicted here is found to be symmetric about the peak value of the photon energy at Eγ = MD_(s)/4.

  6. LHCb: Radiative decays of B hadrons at LHCb

    CERN Multimedia

    Soomro, F

    2009-01-01

    Flavour physics is an excellent probe of physics beyond the Standard Model. It offers the possibility to measure effects from heavy virtual particles with masses above the experimental reach in terms of direct production. LHCb is well positioned to exploit the large statistics of B hadrons available at LHC, to make competitive measurements in various radiative decays like B_d->K^{*} , B_s\\phi\\gamma, \\Lambda_b->\\Lambda ^{0\\gamma} and B^+->\\phiK^{+\\gamma}.. For example, the direct CP asymmetry in K^{*\\gamma} decay can be measured to the level of 1.8%[1], better than the current experimental accuracy, with only 100 pb-1of integrated luminosity.

  7. Formation and decay of the inner electron radiation belt

    Science.gov (United States)

    Su, Y. J.; Selesnick, R.

    2016-12-01

    The inner electron radiation belt was found, early in the space age, to be highly variable with rapid injections followed by slower decay. Highly structured energy spectra were also observed (now known in energy-time spectrograms as "zebra stripes"). Inner belt formation was explained by inward diffusion. However, even the fastest diffusion is expected to require a period of many days, while observations show frequent rapid injections across the entire inner belt (as low as L=1.2) during periods of injections, slow decay, and structured energy spectra, as observed from Van Allen Probes for electrons with energies of 100-400 keV, by the action of large-scale electric fields. In addition, a case study of a non-diffusive fast injection event that occurred on March 17, 2013, is simulated by a test particle code which demonstrates the sensitivity of electron intensity to the selected electric field model.

  8. Radiative decays and the nature of heavy quarkonia

    CERN Document Server

    Garcia i Tormo, Xavier; Soto, Joan; Tormo, Xavier Garcia i

    2006-01-01

    We argue that the photon spectra in radiative decays of various heavy quarkonium states provide important information on their nature. If two of these states are in the strong coupling regime, we are able to produce a parameter-free model independent formula, which holds at next-to-leading order and includes both direct and fragmentation contributions. When the formula is checked against recent CLEO data, it indicates that both the Upsilon (2S) and the Upsilon (3S) states are in the strong coupling regime whereas the Upsilon (1S) is not.

  9. Gluonic Mesons in $J/\\Psi$ Radiative Decay

    CERN Document Server

    Page, P R; Page, Philip R.; Li, Xue-Qian

    1996-01-01

    The eta(1760) may be significantly produced in J/Psi radiative decay. We deduce from experimental data that its branching ratio to two gluons is bounded, 0.4 +- 0.3 gg) < 0.9 +- 0.3, consistent with gluonic admixture. Moreover, it may be the isoscalar partner of the gluonic (hybrid) meson candidate pi(1800). Two-gluon coupling of hybrids is estimated in a spectator model to be considerably larger than that of quarkonium. In addition, the two-photon coupling of eta(1760) is estimated to be 1.4 +- 0.7 keV.

  10. Universality of nonperturbative QCD effects in radiative B-decays

    CERN Document Server

    Descotes-Genon, S

    2003-01-01

    We demonstrate, by an explicit one-loop calculation, that at leading twist the nonperturbative effects in B -> gamma l nu, B -> gamma gamma and B -> gamma l+ l- radiative decays are contained in a common multiplicative factor (\\Lambda_B(E_\\gamma), where E_\\gamma is the energy of the photon). We argue that this result holds also at higher orders. Ratios of the amplitudes for these processes do not depend on scales below the mass of the B-meson (M_B), and can be calculated as perturbative series in \\alpha_s(M_B)

  11. Symmetry limit properties of decay amplitudes with mirror matter admixtures

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    We extend our previous analysis on the symmetry limit properties of non-leptonic and weak radiative decay amplitudes of hyperons in a scheme of mirror matter admixtures in physical hadrons to include the two-body non-leptonic decays of $\\Omega^-$ and the two photon and two pion decays of kaons. We show that the so-called parity-conserving amplitudes predicted for all the decays vanish in the strong flavor SU(3) symmetry limit. We also establish the specific conditions under which the corresponding so-called parity-violating amplitudes vanish in the same limit.

  12. Leptonic and charged kaon decay modes of the $\\phi$ meson measured in heavy-ion collisions at the CERN Super Proton Synchrotron

    CERN Document Server

    Adamova, D; Antonczyk, D; Appelshäuser, H; Belaga, V; Bielcikova, J; Braun-Munzinger, P; Busch, O; Cherlin, A; Damjanovic, S; Dietel, T; Dietrich, L; Drees, A; Esumi, S I; Filimonov, K; Fomenko, K; Fraenkel, Zeev; Garabatos, C; Glässel, P; Hering, G; Holeczek, J; Kushpil, V; Ludolphs, W; Maas, A; Marin, A; Milosevic, J; Miskowiec, D; Ortega, R; Panebratsev, Yu A; Petchenova, O Yu; Petracek, V; Radomski, S; Rak, J; Ravinovich, I; Rehak, P; Sako, H; Schmitz, W; Schükraft, J; Sedykh, S; Shimansky, S S; Stachel, J; Sumbera, M; Tilsner, H; Tserruya, Itzhak; Tsiledakis, G; Wessels, J P; Wienold, T; Wurm, J P; Yurevich, S; Yurevich, V

    2006-01-01

    We report a measurement of $\\phi$ meson production in central Pb+Au collisions at E$_{lab}$/A=158 GeV. For the first time in heavy-ion collisions, $\\phi$ mesons were reconstructed in the same experiment both in the K$^+$K$^-$ and the dilepton decay channel. Near mid-rapidity, this yields rapidity densities, corrected for production at the same rapidity value, of 2.05 +- 0.14(stat) +- 0.25(syst) and 2.04 +- 0.49(stat)+-{0.32}(syst), respectively. The shape of the measured transverse momentum spectra is also in close agreement in both decay channels. The data rule out a possible enhancement of the $\\phi$ yield in the leptonic over the hadronic channel by a factor larger than 1.6 at 95% CL.

  13. A search for the decay of a B meson into a kaon and a tau lepton pair at the BaBar experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cheaib, Racha [McGill Univ., Montreal, QC (Canada)

    2016-08-13

    The flavour changing neutral current (FCNC) process, $B^+$ → $K^+ τ^+ τ^-$ highly suppressed in the Standard Model (SM). This decay is forbidden at tree level and only occurs at lowest order via one-loop diagrams.$B^+$ → $K^+ τ^+ τ^-$ thus has the potential to provide a stringent test of the SM and a fertile ground for new physics searches. Contributions due to virtual particles in the loop allow one to probe, at relatively low energies, new physics at large mass scales. We search for the rare FCNC process $B^+$ → $K^+ τ^+ τ^-$ using data collected by the BaBaR detector at the SLAC National Accelerator Laboratory. The BaBaR data sample corresponds to a total integrated luminosity, at the energy of the Τ(4S) resonance, of 424.4 $fb^-1$ and 471 million $B\\bar{B}$ pairs. For this search, hadronic $B_{tag}$ reconstruction is employed, where one B is exclusively reconstructed via one of many possible hadronic modes. The remaining decay products in an event are then attributed to the signal B, on which the search for $B^+$ → $K^+ τ^+ τ^-$ is performed. Each τ is required to decay leptonically, into either an electron or a muon and the lepton neutrinos. Furthermore, a multi-variate analysis technique (neural network) is used to select for signal events and suppress dominant background modes. No significant signal is observed. The resulting branching fraction is measured to be $\\beta(B^+$ → $K^+ τ^+)$ = $1.31^{0:66}_{-0:61}$(stat.) $^{+0:35}_{-0:25}$(sys.) x 10$^{-3}$, which is consistent with zero at the 1.9σ level, with an upper limit of 2.25 x 10$^{-3}$, at the 90% confidence level.

  14. Kaon Production and Interaction

    CERN Document Server

    Wolke, B M; Budzanowski, A; Czyzykiewicz, R; Grzonka, D; Jarczyk, L; Kamys, B; Khoukaz, A; Kilian, K; Kowina, P; Lister, T A; Moskal, P; Oelert, Walter; Rozek, T; Santo, R; Schepers, G; Sefzick, T; Siemaszko, M; Smyrski, J; Steltenkamp, S; Strzalkowski, A; Winter, P; Wüstner, P; Zipper, W; Wolke, By M.

    2003-01-01

    Exclusive data on both the elementary kaon and antikaon production channels have been taken at the cooler synchrotron COSY in proton-proton scattering. In the kaon--hyperon production an enhancement by one order of magnitude of the Lambda/Sigma0 ratio has been observed at excess energies below Q=13 MeV compared to data at higher excess energies (Q>300 MeV). New results obtained at the COSY-11 facility explore the transition region between the regime of this low-energy Sigma0 suppression and excess energies of 60 MeV. A comparison of the energy dependence of the Lambda and Sigma0 total cross sections exhibits distinct qualitative differences between both hyperon production channels. Studies of kaon-antikaon production have been motivated especially by the ongoing discussion about the nature of the scalar resonances f0(980) and a0(980) coupling to the K anti-K channel. For the reaction pp->ppK+K- a first total cross section value is reported at an excess energy of Q=17 MeV, i.e. below the phi threshold. Calcula...

  15. Radiative decay modes of the D{sup 0} meson

    Energy Technology Data Exchange (ETDEWEB)

    Asner, D.M.; Gronberg, J.; Hill, T.S.; Lange, D.J.; Morrison, R.J.; Nelson, H.N.; Nelson, T.K.; Roberts, D.; Ryd, A. [University of California, Santa Barbara, California 93106 (United States); Balest, R.; Behrens, B.H.; Ford, W.T.; Gritsan, A.; Park, H.; Roy, J.; Smith, J.G. [University of Colorado, Boulder, Colorado 80309-0390 (United States); Alexander, J.P.; Baker, R.; Bebek, C.; Berger, B.E.; Berkelman, K.; Bloom, K.; Boisvert, V.; Cassel, D.G.; Crowcroft, D.S.; Dickson, M.; von Dombrowski, S.; Drell, P.S.; Ecklund, K.M.; Ehrlich, R.; Foland, A.D.; Gaidarev, P.; Gibbons, L.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Hopman, P.I.; Kandaswamy, J.; Kim, P.C.; Kreinick, D.L.; Lee, T.; Liu, Y.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Ogg, M.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Valant-Spaight, B.; Ward, C. [Cornell University, Ithaca, New York 14853 (United States); Athanas, M.; Avery, P.; Jones, C.D.; Lohner, M.; Patton, S.; Prescott, C.; Yelton, J.; Zheng, J. [University of Florida, Gainesville, Florida 32611 (United States); Brandenburg, G.; Briere, R.A.; Ershov, A.; Gao, Y.S.; Kim, D.Y.; Wilson, R.; Yamamoto, H. [Harvard University, Cambridge, Massachusetts 02138 (United States); Browder, T.E.; Li, Y.; Rodriguez, J.L. [University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Hans, R.M.; Johnson, E.; Karliner, I.; Marsh, M.A.; Palmer, M.; Selen, M.; Thaler, J.J. [University of Illinois, Urbana-Champaign, Illinois 61801 (United States); Edwards, K.W. [Carleton University, Ottawa, Ontario, Canada K1S 5B6 and the Institute of Particle Physics (Canada); Bellerive, A.; Janicek, R.; MacFarlane, D.B.; Patel, P.M. [McGill University, Montreal, Quebec, Canada H3A 2T8 and the Institute of Particle Physics (Canada); Sadoff, A.J. [Ithaca College, Ithaca, New York 14850 (United States); Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; and others

    1998-11-01

    In this paper we describe a search for four radiative decay modes of the D{sup 0} meson: D{sup 0}{r_arrow}{phi}{gamma}, D{sup 0}{r_arrow}{omega}{gamma}, D{sup 0}{r_arrow}{bar K}{sup {asterisk}}{gamma}, and D{sup 0}{r_arrow}{rho}{sup 0}{gamma}. We obtain 90{percent} C.L. upper limits on the branching ratios of these modes of 1.9{times}10{sup {minus}4}, 2.4{times}10{sup {minus}4}, 7.6{times}10{sup {minus}4}, and 2.4{times}10{sup {minus}4}, respectively. {copyright} {ital 1998} {ital The American Physical Society}

  16. Pion radiative weak decay from the instanton vacuum

    Science.gov (United States)

    Shim, Sang-In; Kim, Hyun-Chul

    2017-09-01

    We investigate the vector and axial-vector form factors for the pion radiative weak decays π+ →e+νe γ and π+ →e+νee+e-, based on the gauged effective chiral action from the instanton vacuum in the large Nc limit. The nonlocal contributions, which arise from the gauging of the action, enhance the vector form factor by about 20%, whereas the axial-vector form factor is reduced by almost 30%. Both the results for the vector and axial-vector form factors at the zero momentum transfer are in good agreement with the experimental data. The dependence of the form factors on the momentum transfer is also studied. The slope parameters are computed and compared with other works.

  17. Photon energy scale determination and commissioning with radiative Z decays

    Directory of Open Access Journals (Sweden)

    Bondu Olivier

    2012-06-01

    Full Text Available The CMS electromagnetic calorimeter (ECAL is composed of 75848 lead-tungstate scintillating crystals. It has been designed to be fast, compact, and radiation hard, with fine granularity and excellent energy resolution. Obtaining the design resolution is a crucial challenge for the SM Higgs search in the two photon channel at the LHC, and more generally good photon calibration and knowledge of the photon energy scale is required for analyses with photons in the final state. The behavior of photons and electrons in the calorimeter is not identical, making the use of a dedicated standard candle for photons, complementary to the canonical highyield Z decay to electrons, highly desirable. The use of Z decays to a pair of muons, where one of the muons emits a Bremsstrahlung photon, can be such a standard candle. These events, which can be cleanly selected, are a source of high-purity, relatively high-pt photons. Their kinematics are well-constrained by the Z boson mass and the precision on the muon momenta, and can be used for numerous calibration and measurement purposes. This proceeding presents the event selection method and the results of the photon energy scale measurement via Z0 → μμγ events as well as their use in evaluating the efficiency of photon identification requirements, based on data recorded by the CMS experiment in 2010.

  18. Search for fj(2220) in radiative J/psi decays

    Energy Technology Data Exchange (ETDEWEB)

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Princeton U. /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2010-07-30

    We present a search for f{sub J}(2220) production in radiative J/{psi} {yields} {gamma}f{sub J}(2220) decays using 460 fb{sup -1} of data collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} collider. The f{sub J}(2220) is searched for in the decays to K{sup +}K{sup -} and K{sub S}{sup 0}K{sub S}{sup 0}. No evidence of this resonance is observed, and 90% confidence level upper limits on the product of the branching fractions for J/{psi} {yields} {gamma}f{sub J}(2220) and f{sub J}(2220) {yields} K{sup +}K{sup -}(K{sub S}{sup 0}K{sub S}{sup 0}) as a function of spin and helicity are set at the level of 10{sup -5}, below the central values reported by the Mark III experiment.

  19. Large N Approach to Kaon Decays and Mixing 28 Years Later: Delta I = 1/2 Rule, \\hat B_K and Delta M_K

    CERN Document Server

    Buras, Andrzej J; Bardeen, William A

    2014-01-01

    We review and update our results for K-> pipi decays and K^0-\\bar K^0 mixing obtained by us in the 1980s within an approach based on the dual representation of QCD as a theory of weakly interacting mesons for large N colours. In our analytic approach the dynamics behind the enhancement of ReA_0 and suppression of ReA_2, the so-called Delta I = 1/2 rule for K-> pi pi decays, has a simple structure: the usual octet enhancement through quark-gluon renormalization group evolution down to the scales O(1 GeV) is continued as a meson evolution down to zero momentum scales at which the factorization of hadronic matrix elements is at work. The inclusion of lowest-lying vector meson contributions in addition to the pseudoscalar ones and of Wilson coefficients in a momentum scheme improves significantly the matching between quark-gluon and meson evolutions. In particular, the anomalous dimension matrix governing the meson evolution exhibits the structure of the known anomalous dimension matrix in the quark-gluon evoluti...

  20. Search for Hadronic Decays of a Light Higgs Boson in the Radiative Decay

    Energy Technology Data Exchange (ETDEWEB)

    Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Milanes, D.A.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.

    2012-02-16

    The authors search for hadronic decays of a light Higgs boson (A{sup 0}) produced in radiative decays of an {Upsilon}(2S) or {Upsilon}(3S) meson, {Upsilon} {yields} {gamma}A{sup 0}. The data have been recorded by the BABAR experiment at the {Upsilon}(3S) and {Upsilon}(2S) center of mass energies, and include (121.3 {+-} 1.2) x 10{sup 6} {Upsilon}(3S) and (98.3 {+-} 0.9) x 10{sup 6} {Upsilon}(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions {beta}({Upsilon}(nS) {yields} {gamma}A{sup 0}) {center_dot} {beta}(A{sup 0} {yields} hadrons) (n = 2 or 3) that range from 1 x 10{sup -6} for an A{sup 0} mass of 0.3 GeV/c{sup 2} to 8 x 10{sup -5} at 7 GeV/c{sup 2}.

  1. New Physics Patterns in $\\varepsilon^\\prime/\\varepsilon$ and $\\varepsilon_K$ with Implications for Rare Kaon Decays and $\\Delta M_K$

    CERN Document Server

    Buras, Andrzej J

    2016-01-01

    The SM prediction for the ratio $\\varepsilon^\\prime/\\varepsilon$ appears to be significantly below the experimental data. Also $\\varepsilon_K$ in the SM tends to be below the data. Any NP removing these anomalies will first of all have impact on flavour observables in the $K$ meson system, in particular on rare $K$ decays and $\\Delta M_K$. Restricting the operators contributing to $\\varepsilon^\\prime/\\varepsilon$ to the SM ones and to the corresponding primed operators, NP contributions are quite generally dominated either by QCD penguin (QCDP) operators $Q_6(Q_6^\\prime)$ or electroweak penguin (EWP) operators $Q_8(Q_8^\\prime)$ with rather different implications for other flavour observables. We discuss general models with tree-level $Z$ and $Z^\\prime$ flavour violating exchanges and few specific models. We find that simultaneous enhancements of $\\varepsilon^\\prime/\\varepsilon$, $\\varepsilon_K$, $\\mathcal{B}(K_L\\to\\pi^0\

  2. Calculation of Non-Leptonic Kaon Decay Amplitudes from $K\\to\\pi$ Matrix Elements in Quenched Domain-Wall QCD

    CERN Document Server

    Noaki, J I; Aoki, Y; Burkhalter, R; Ejiri, S; Fukugita, M; Hashimoto, S; Ishizuka, N; Iwasaki, Y; Izubuchi, T; Kanaya, K; Kaneko, T; Kuramashi, Y; Lesk, V I; Nagai, K I; Okawa, M; Taniguchi, Y; Ukawa, A; Yoshié, T

    2001-01-01

    We explore application of the domain wall fermion formalism of lattice QCD to calculate the $K\\to\\pi\\pi$ decay amplitudes in terms of the $K\\to\\pi$ and $K\\to 0$ hadronic matrix elements through relations derived in chiral perturbation theory. Numerical simulations are carried out in quenched QCD using domain-wall fermion action for quarks and an RG-improved gauge action for gluons on a $16^3\\times 32\\times 16$ and $24^3\\times 32\\times 16$ lattice at $\\beta=2.6$ corresponding to the lattice spacing $1/a\\approx 2$GeV. Quark loop contractions which appear in Penguin diagrams are calculated by the random noise method, and the $\\Delta I=1/2$ matrix elements which require subtractions with the quark loop contractions are obtained with a statistical accuracy of about 10%. We confirm the chiral properties required of the $K\\to\\pi$ matrix elements. Matching the lattice matrix elements to those in the continuum at $\\mu=1/a$ using the perturbative renormalization factor to one loop order, and running to the scale $\\mu=m...

  3. Kaon-condensed hypernuclei as highly dense self-bound objects

    CERN Document Server

    Muto, Takumi

    2008-01-01

    The structure of $K^-$-condensed hypernuclei, which may be produced in the laboratory in strangeness-conserving processes, is investigated using an effective chiral Lagrangian for the kaon-baryon interaction, combined with a nonrelativistic baryon-baryon interaction model. It is shown that a large number of negative strangeness is needed for the formation of highly dense and deeply bound state with kaon condensates and that part of the strangeness should be carried by hyperons mixed in the nucleus. The properties of kaon-condensed hypernuclei such as the ground state energy and particle composition are discussed. Such a self-bound object has a long lifetime and may decay only through weak interaction processes. Comparison with other possible nuclear states is also made, such as kaon-condensed nuclei without mixing of hyperons and noncondensed multistrange hypernuclei. Implications of kaon-condensed hypernuclei for experiments are mentioned.

  4. Measurement of the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay with the KLOE detector

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bossi, F; Branchini, P; Campana, P; Capon, G; Capussela, T; Ceradini, F; Cesario, F; Chi, S; Chiefari, G; Ciambrone, P; Crucianelli, F; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martemyanov, M; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Sibidanov, A; Spadaro, T; Testa, M; Tortora, L; Valente, P; Venanzoni, G; Versaci, R; Xu, G

    2008-01-01

    We have measured the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay, using about 20 million tagged K+ mesons collected with the KLOE detector at DAFNE, the Frascati phi-factory. Signal counts are obtained from the fit of the distribution of the momentum of the charged decay particle in the kaon rest frame. The result, inclusive of final-state radiation, is BR(K+ -> pi+ pi0 (gamma))=0.2065+/-0.0005_{stat}+/- 0.0008_{syst}.

  5. Studying radiative B decays with the Atlas detector; Etude des desintegrations radiatives des mesons B dans le detecteur ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Viret, S

    2004-09-01

    This thesis is dedicated to the study of radiative B decays with the ATLAS detector at the LHC (large hadron collider). Radiative decays belong to the rare decays family. Rare decays transitions involve flavor changing neutral currents (for example b {yields} s{gamma}), which are forbidden at the lowest order in the Standard Model. Therefore these processes occur only at the next order, thus involving penguin or box diagrams, which are very sensitive to 'new physics' contributions. The main goal of our study is to show that it would be possible to develop an online selection strategy for radiative B decays with the ATLAS detector. To this end, we have studied the treatment of low energy photons by the ATLAS electromagnetic calorimeter (ECal). Our analysis shows that ATLAS ECal will be efficient with these particles. This property is extensively used in the next section, where a selection strategy for radiative B decays is proposed. Indeed, we look for a low energy region of interest in the ECal as soon as the level 1 of the trigger. Then, photon identification cuts are performed in this region at level 2. However, a large part of the proposed selection scheme is also based on the inner detector, particularly at level 2. The final results show that large amounts of signal events could be collected in only one year by ATLAS. A preliminary significance (S/{radical}B) estimation is also presented. Encouraging results concerning the observability of exclusive radiative B decays are obtained. (author)

  6. Theoretical perspective on rare and radiative charm decays

    CERN Document Server

    Fajfer, Svjetlana

    2015-01-01

    Recent experimental bounds on rare charm decays offer a chance to improve our theoretical understanding of physics present in $c \\to u \\gamma$ and $c \\to u l^+ l^-$ transitions. Standard Model and New Physics contributions are reviewed for inclusive and exclusive $D \\to V\\gamma$, $D^+ \\to \\pi^+ l^+ l^-$, $D \\to l^+ l^-$ decays. Observables important for search of New Physics are discussed. Possibility to observe CP violation in rare charm decays is questioned.

  7. Inclusive neutral kaon production in 70 GeV/c K/sup +/p interactions

    CERN Document Server

    Barth, Monique; Beaufays, J; Berejnov, V V; Caso, C; Chliapnikov, P V; Contri, R; De Clercq, C; De Wolf, E A; Drevermann, H; Dumont, J J; Dziembowski, Z; Fenyuk, A; Fontanelli, F; Gatignon, L; Gerdyukov, L N; Goldschmidt-Clermont, Yves; Grard, F; Gritsaenko, I; Gumenyuk, S A; Hanton, J; Harigel, G G; Johnson, D P; Kittel, E W; Kubic, V; Lemonne, J; Lugovsky, S B; Metzger, W J; Milstene, C; Monge, R; Nikitin, S; Nikolaenko, V; Peeters, P; Petrovikh, Y; Porte, J P; Ronjin, V; Ross, R T; Schotanus, D J; Squarcia, S; Stergiou, Athanase; Theocharopoulos, P; Trevisan, U; Utochkin, B; Van de Walle, R T; Van der Poel, P A; Vassiliadis, G; Yarba, V A

    1981-01-01

    The inclusive production of neutral kaons in 70 GeV/c K/sup +/p interactions is studied with the CERN BEBC bubble chamber. The (semi-) inclusive cross sections are interpreted in terms of the various strangeness channels leading to neutral kaon production. The invariant inclusive cross section for kaon production is studied as a function of p/sub t//sup 2/ and the Feynman variable x. The latter distributions are considered both 'raw' and corrected for the presence of K/sup 0/'s resulting from K* decay. They are compared with the prediction expected from the Regge-Mueller formalism, the recombination model and fragmentation models. (24 refs).

  8. Analysis Of Neutral-d Decays To A Charged Kaon, A Charged Pion, And A Neutral Pion: Search For Neutral-d Mixing, And Measurements Of The Doubly Cabibbo-suppressed Decay Rate And Resonance Contributions

    CERN Document Server

    Wilson, M G

    2005-01-01

    Analyzing D0 → K +π- π0 decays, herein are presented the methods and results of a search for D0- D¯0 mixing, a measurement of the branching ratio R ≡ Γ(D0 → K+π- π0)/Γ( D0 → K-π +π0), and measurements of the contributions from D0 → K+π -, K*+π-, K*0π0; 230.4fb-1 of data collected from the BABAR detector at the PEP-II collider during 2000-2004 (Runs 1-4) are analyzed. An event-level tagging technique is developed, which facilitates the accurate determination of doubly Cabibbo-suppressed resonance contributions by suppressing background from Cabibbo-favored decays. The branching ratio is measured as R = (0.214 ± 0.008 (stat)±0.008 (syst))%, with (46.1±3.3 (stat)±2.9 (syst))% of D0 → K+π -π0 decays proceeding through the channel D0 → K*+π -. The data are consistent with the null-D- mixing h...

  9. Contribution of CPLEAR to the physics of the neutral-kaon system

    Energy Technology Data Exchange (ETDEWEB)

    Angelopoulos, A.; Apostolakis, A.; Aslanides, E.; Backenstoss, G.; Bargassa, P.; Behnke, O.; Benelli, A.; Bertin, V.; Blanc, F.; Bloch, P.; Carlson, P.; Carroll, M.; Cawley, E.; Chertok, M.B.; Danielsson, M.; Dejardin, M.; Derre, J.; Ealet, A.; Eleftheriadis, C.A.; Faravel, L.; Fetscher, W.; Fidecaro, M.; Filipcic, A.; Francis, D.; Fry, J.; Gabathuler, E.; Gamet, R.; Gerber, H.-J.; Go, A.; Haselden, A.; Hayman, P.J.; Henry-Couannier, F.; Hollander, R.W.; Jon-And, K.; Kettle, P.-R.; Kokkas, P.; Kreuger, R.; Le Gac, R.; Leimgruber, F.; Mandic, I.; Manthos, N.; Marel, G.; Mikuz, M.; Miller, J.; Montanet, F.; Muller, A.; Nakada, T.; Pagels, B.; Papadopoulos, I.; Pavlopoulos, P.; Polivka, G.; Rickenbach, R.; Roberts, B.L.; Ruf, T.; Schaefer, M.; Schaller, L.A.; Schietinger, T.; Schopper, A.; Schune, P.; Tauscher, L.; Thibault, C.; Touchard, F.; Touramanis, C.; Van Eijk, C.W.E.; Vlachos, S.; Weber, P.; Wigger, O.; Wolter, M.; Zavrtanik, D.; Zimmerman, D

    1999-04-01

    We report the results of the CPLEAR experiment on CP-, T- and CPT-symmetries in the neutral kaon system. CP-violation parameters are given for different decay channels. For the first time T-violation is measured by a direct method using semileptonic decays. The CPT symmetry in the kaons decays is tested through the parameters Im({delta}), from the Bell-Steinberger relation, with a precision of 10{sup -5} and Re({delta}) with a precision of a few 10{sup -4} (two order of magnitude better than the previous measurement). These two measurements allow us to bound the difference in mass and width of K{sup 0} and K-bar{sup 0} to be equal within 10{sup -18} GeV. In the limit of CPT invariance in the neutral kaon decays, the K{sup 0} and K-bar{sup 0} masses are equal within 10{sup -19} GeV.

  10. Radiative corrections to $K_{l3}$ decays

    CERN Document Server

    Cirigliano, V; Neufeld, H; Rupertsberger, H W; Talavera, P

    2002-01-01

    We present a complete calculation of the K_{l3} decays K^+ --> pi^0 l^+ nu_l and K^0 --> pi^- l^+ nu_l to O(p^4, (m_d-m_u) p^2, e^2 p^2) in chiral perturbation theory with virtual photons and leptons. We introduce the concept of generalized form factors and kinematical densities in the presence of electromagnetism, and propose a possible treatment of the real photon emission in K^+_{l3} decays. We illustrate our results by applying them to the extraction of the Kobayashi--Maskawa matrix element |V_{us}| from the experimental K^+_{e3} decay parameters.

  11. Kaon photoproduction off proton

    Science.gov (United States)

    Skoupil, Dalibor; Bydžovský, Petr

    2016-11-01

    We have recently constructed our version of the Regge-plus-resonance (RPR) model and two variants of an isobar model for photoproduction of kaons on the proton, utilizing new experimental data from CLAS, LEPS, and GRAAL collaborations for adjusting free parameters of the models. Higher-spin nucleon (3/2 and 5/2) and hyperon (3/2) resonances were included using the consistent formalism by Pascalutsa and found to play an important role in data description. The set of chosen nucleon resonances in our new isobar models agrees well with the set of the most probable contributing states determined in the Bayesian analysis with the RPR model whilst only 6 out of 10 N*'s selected in the RPR fit of ours overlap with the nucleon resonant states in the Bayesian analysis. Results of two versions of the isobar model are compared to the new version of the RPR model and experimental data in the third-resonance region and their properties are discussed. We place an emphasis on the choice of resonances, the predictions in the forward- and backward-angle region as well as the choice of the hadron form factor.

  12. Kaon photoproduction off proton

    Directory of Open Access Journals (Sweden)

    Skoupil Dalibor

    2016-01-01

    Full Text Available We have recently constructed our version of the Regge-plus-resonance (RPR model and two variants of an isobar model for photoproduction of kaons on the proton, utilizing new experimental data from CLAS, LEPS, and GRAAL collaborations for adjusting free parameters of the models. Higher-spin nucleon (3/2 and 5/2 and hyperon (3/2 resonances were included using the consistent formalism by Pascalutsa and found to play an important role in data description. The set of chosen nucleon resonances in our new isobar models agrees well with the set of the most probable contributing states determined in the Bayesian analysis with the RPR model whilst only 6 out of 10 N*’s selected in the RPR fit of ours overlap with the nucleon resonant states in the Bayesian analysis. Results of two versions of the isobar model are compared to the new version of the RPR model and experimental data in the third-resonance region and their properties are discussed. We place an emphasis on the choice of resonances, the predictions in the forward- and backward-angle region as well as the choice of the hadron form factor.

  13. Radiative distortion of kinematic edges in cascade decays

    CERN Document Server

    Beneke, Martin; Mück, Alexander; Ubiali, Maria

    2016-01-01

    Kinematic edges of cascade decays of new particles produced in high-energy collisions may provide important constraints on the involved particles' masses. For the exemplary case of gluino decay $\\tilde{g}\\to q\\bar q \\tilde{\\chi}$ into a pair of quarks and a neutralino through a squark resonance, we study the hadronic invariant mass distribution in the vicinity of the kinematic edge. We perform a next-to-leading order calculation in the strong coupling $\\alpha_s$ and the ratio of squark width and squark mass $\\Gamma_\\tilde{q}/m_\\tilde{q}$, based on a systematic expansion in $\\Gamma_\\tilde{q}/m_\\tilde{q}$. The separation into hard, collinear and soft contributions elucidates the process dependent and universal features of distributions in the edge region, represented by on-shell decay matrix elements, universal jet functions and a soft function that depends on the resonance propagator and soft Wilson lines.

  14. Photoproduction of the kaon(+)kaon(-)(1750)

    Science.gov (United States)

    Mitchell, Ryan Edward

    2003-07-01

    While photoproduction has often been advertised as an important environment in which to study light meson spectroscopy, solid experimental results are sparse. In fact, beyond the relatively straightforward photoproduction of the rho, o, and φ mesons, the few results of exclusive photoproduction that do exist are poorly understood, and several, perhaps, have even been misinterpreted. After extensively reviewing the sometimes tenuous history of the exclusive photoproduction of the "rho'(1600)," the "opi0(1250)," the "o(1650)," and the "K+K -(1750)," new results from the E831/FOCUS photoproduction experiment at Fermilab are presented which address the interpretation of the K+K-(1750). This enhancement in low-pT K +K- pairs at a mass near 1750 MeV/c2 has been observed by several previous photoproduction experiments, but, despite several apparent inconsistencies, it has always been interpreted as the JPC = 1-- φ(1680) meson. With nearly two orders of magnitude more events than any previous observation of the K+ K-(1750), and based on precise measurements of its mass and width, and its absence from the K* K final state, the FOCUS data can finally render this interpretation implausible. In addition, several steps have been taken towards establishing a new interpretation. Based on limited angular analyses of its decay and the beam energy dependence of its production, we argue that, in the absence of any wild interference scenarios, the K+ K-(1750) has JPC ≠ 1--, and, in fact, the most likely assignment appears to be 2++. It is hoped that this work can help set the stage for future reevaluations and new insights in photoproduction.

  15. Kaon Theory News

    CERN Document Server

    Buras, Andrzej J

    2015-01-01

    During the last fifteen years B_{s,d} decays, B_{s,d}^0-\\bar B^0_{s,d} mixings, CP-violating asymmetries S_{\\psi K_S} and S_{\\psi\\phi} provided the dominant information about the pattern of flavour violation within the SM and its extensions. We emphasize that in the coming years K meson physics will certainly strike back through the measurements of the branching ratios of theoretically very clean decays K^+->pi^+\

  16. Rare radiative decay of the $B_{c}$ meson

    CERN Document Server

    Barik, N; Kar, S; Dash, P C

    2001-01-01

    We study the decays B/sub c/ to D* gamma and B/sub c/ to D/sub s/* gamma in the relativistic independent quark model based on the confining potential in the scalar-vector harmonic form. Out of the two competing mechanisms contributing to these decays, we find that the weak annihilation contribution dominates the electromagnetic penguin one. Considering contributions from both mechanisms, total decay widths and branching ratios are predicted as Gamma (B/sub c/ to D* gamma )=5.22*10/sup -18/ GeV, Gamma (B/sub c/ to D/sub s/* gamma ) =1.98*10/sup -16/ GeV and Br(B/sub c/ to D* gamma ) approximately =3.64*10/sup -6/, Br(B/sub c/ to D/sub s/* gamma ) approximately =1.39*10/sup -4/ with tau /sub Bc/=0.46 ps. The decays B/sub c/ to D /sub s/* gamma can well be studied at CERN LHC in the near future. (33 refs).

  17. eta Physics and phi Radiative Decays at Kloe

    CERN Document Server

    Ambrosino, F; Antonelli, M; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bocci, V; Bossi, F; Branchini, P; Caloi, R; Campana, P; Capon, G; Capussela, T; Ceradini, F; Chi, S; Chiefari, G; Ciambrone, P; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Falco, S; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Finocchiaro, G; Fiore, S; Forti, C; Franzini, P; Gati, C; Gauzzi, P; Giocannella, S; Gorini, E; Graziani, E; Incagli, M; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martini, M; Massartti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Scuri, F; Sfiligoi, I; Spadaro, T; Testa, M; Tortora, L; Valente, P; Valeriani, B; Venanzoni, G; Versaci, R; Xu, G

    2007-01-01

    Here we present KLOE results on the phi meson decays in pi0 pi0 gamma, pi+ pi- gamma and eta pi0 gamma, the measurement of the ratio Br(phi to eta' gamma)/Br(phi to eta gamma) with the estimate of the eta' gluonium content and the measurement of the eta mass.

  18. Radiative and dilepton decays of the hadronic molecule Zc(3900)+

    CERN Document Server

    Gutsche, Thomas; Lyubovitskij, Valery E

    2014-01-01

    The newly observed hidden-charm meson Zc(3900) with quantum numbers J(P) = 1(+) is considered as a hadronic molecule composed of DD*. We give detailed predictions for the decay modes Zc(+) -> J/psi + pi(+) + gamma and Zc(+) -> J/psi + pi(+) + l(+) + l(-) (l = e, mu) in a phenomenological Lagrangian approach.

  19. Dark energy and the Rutherford-Soddy radiative decay law

    CERN Document Server

    Bento, M C

    2009-01-01

    It is argued that a putative evolution of the fundamental couplings of strong and weak interactions via coupling to dark energy through a generalized Bekenstein-type model may, for a linear model of variation, cause deviations on the statistical nuclear decay Rutherford-Soddy law unless bounds are imposed on the parameters of this variation.

  20. Activated barrier crossing dynamics in the non-radiative decay of NADH and NADPH

    Energy Technology Data Exchange (ETDEWEB)

    Blacker, Thomas S., E-mail: t.blacker@ucl.ac.uk [Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London WC1E 6BT (United Kingdom); Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom); Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT (United Kingdom); Marsh, Richard J., E-mail: richard.marsh@ucl.ac.uk [Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom); Duchen, Michael R., E-mail: m.duchen@ucl.ac.uk [Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT (United Kingdom); Bain, Angus J., E-mail: a.bain@ucl.ac.uk [Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London WC1E 6BT (United Kingdom); Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)

    2013-08-30

    Highlights: ► NADH and NADPH have a high rate of non-radiative excited state decay. ► Conformational relaxation is shown to be a significant non-radiative pathway. ► The Kramers equation describes the barrier crossing dynamics of the relaxation. ► Conformational restriction upon enzyme binding will alter NAD(P)H lifetimes. - Abstract: In live tissue, alterations in metabolism induce changes in the fluorescence decay of the biological coenzyme NAD(P)H, the mechanism of which is not well understood. In this work, the fluorescence and anisotropy decay dynamics of NADH and NADPH were investigated as a function of viscosity in a range of water–glycerol solutions. The viscosity dependence of the non-radiative decay is well described by Kramers and Kramers–Hubbard models of activated barrier crossing over a wide viscosity range. Our combined lifetime and anisotropy analysis indicates common mechanisms of non-radiative relaxation in the two emitting states (conformations) of both molecules. The low frequencies associated with barrier crossing suggest that non-radiative decay is mediated by small scale motion (e.g. puckering) of the nicotinamide ring. Variations in the fluorescence lifetimes of NADH and NADPH when bound to different enzymes may therefore be attributed to differing levels of conformational restriction upon binding.

  1. Search for bottomonium states in exclusive radiative Upsilon(2S) decays

    CERN Document Server

    Sandilya, S; Mohanty, G B; Adachi, I; Aihara, H; Asner, D M; Aushev, T; Bakich, A M; Bala, A; Bhardwaj, V; Bhuyan, B; Bondar, A; Bonvicini, G; Bozek, A; Bračko, M; Browder, T E; Chen, P; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, S -K; Choi, Y; Cinabro, D; Dalseno, J; Dingfelder, J; Doležal, Z; Drutskoy, A; Dutta, D; Eidelman, S; Farhat, H; Fast, J E; Feindt, M; Ferber, T; Frey, A; Gaur, V; Gabyshev, N; Ganguly, S; Gillard, R; Goh, Y M; Golob, B; Haba, J; Hara, T; Hayasaka, K; Hayashii, H; Hoshi, Y; Hou, W -S; Hsiung, Y B; Hyun, H J; Iijima, T; Ishikawa, A; Itoh, R; Iwasaki, Y; Julius, T; Kah, D H; Kang, J H; Kato, E; Kawai, H; Kawasaki, T; Kiesling, C; Kim, D Y; Kim, H O; Kim, J B; Kim, J H; Kim, Y J; Klucar, J; Ko, B R; Kodyš, P; Korpar, S; Križan, P; Krokovny, P; Kumita, T; Kuzmin, A; Kwon, Y -J; Lange, J S; Lee, S -H; Li, J; Li, Y; Liu, Z Q; Liventsev, D; Lukin, P; Matvienko, D; Miyabayashi, K; Miyata, H; Mizuk, R; Moll, A; Muramatsu, N; Mussa, R; Nagasaka, Y; Nakao, M; Nayak, M; Ng, C; Nisar, N K; Nishida, S; Nitoh, O; Ogawa, S; Okuno, S; Oswald, C; Pakhlova, G; Park, C W; Park, H; Park, H K; Pedlar, T K; Pestotnik, R; Petrič, M; Piilonen, L E; Ritter, M; Röhrken, M; Rostomyan, A; Ryu, S; Sahoo, H; Saito, T; Sakai, K; Sakai, Y; Santelj, L; Sanuki, T; Sato, Y; Savinov, V; Schneider, O; Schnell, G; Semmler, D; Senyo, K; Sevior, M E; Shapkin, M; Shen, C P; Shibata, T -A; Shiu, J -G; Shwartz, B; Sibidanov, A; Simon, F; Sohn, Y -S; Sokolov, A; Solovieva, E; Stanič, S; Starič, M; Steder, M; Sumiyoshi, T; Tamponi, U; Tanida, K; Tatishvili, G; Teramoto, Y; Tsuboyama, T; Uchida, M; Uehara, S; Uglov, T; Unno, Y; Uno, S; Urquijo, P; Vahsen, S E; Van Hulse, C; Vanhoefer, P; Varner, G; Vorobyev, V; Wagner, M N; Wang, C H; Wang, M -Z; Wang, P; Wang, X L; Watanabe, M; Watanabe, Y; Wiechczynski, J; Williams, K M; Won, E; Yabsley, B D; Yamaoka, J; Yamashita, Y; Yashchenko, S; Yuan, C Z; Yusa, Y; Zhang, C C; Zhang, Z P; Zhilich, V; Zupanc, A

    2013-01-01

    We search for bottomonium states in Upsilon(2S)-> (bb-bar) gamma decays with an integrated luminosity of 24.7fb^-1 recorded at the Upsilon(2S) resonance with the Belle detector at KEK, containing (157.8+-3.6) X 10^6 Upsilon(2S) events. The (bb-bar) system is reconstructed in 26 exclusive hadronic final states comprised of charged pions, kaons, protons, and K^0_S mesons. We find no evidence for the state recently observed around 9975 MeV (X_(bb-bar)) in an analysis based on a data sample of 9.3 X 10^6 Upsilon(2S) events collected with the CLEO III detector. We set a 90 % confidence-level upper limit on the branching fraction B[Upsilon(2S)-> X_(bb-bar) gamma] X \\sum_i{B[X_(bb-bar)-> h_i]} eta_b(1S) gamma] X \\sum_i{B[eta_b(1S)-> h_i]}< 3.7 X 10^-6.

  2. Search for Bottomonium States in Exclusive Radiative Υ(2S) Decays

    Science.gov (United States)

    Sandilya, S.; Trabelsi, K.; Mohanty, G. B.; Adachi, I.; Aihara, H.; Asner, D. M.; Aushev, T.; Aziz, T.; Bakich, A. M.; Bala, A.; Bhardwaj, V.; Bhuyan, B.; Bondar, A.; Bonvicini, G.; Bozek, A.; Bračko, M.; Browder, T. E.; Chen, P.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, K.; Chobanova, V.; Choi, S.-K.; Choi, Y.; Cinabro, D.; Dalseno, J.; Dingfelder, J.; Doležal, Z.; Drutskoy, A.; Dutta, D.; Eidelman, S.; Farhat, H.; Fast, J. E.; Feindt, M.; Ferber, T.; Frey, A.; Gaur, V.; Gabyshev, N.; Ganguly, S.; Gillard, R.; Goh, Y. M.; Golob, B.; Haba, J.; Hara, T.; Hayasaka, K.; Hayashii, H.; Hoshi, Y.; Hou, W.-S.; Hsiung, Y. B.; Hyun, H. J.; Iijima, T.; Ishikawa, A.; Itoh, R.; Iwasaki, Y.; Julius, T.; Kah, D. H.; Kang, J. H.; Kato, E.; Kawai, H.; Kawasaki, T.; Kiesling, C.; Kim, D. Y.; Kim, H. O.; Kim, J. B.; Kim, J. H.; Kim, Y. J.; Klucar, J.; Ko, B. R.; Kodyš, P.; Korpar, S.; Križan, P.; Krokovny, P.; Kumita, T.; Kuzmin, A.; Kwon, Y.-J.; Lange, J. S.; Lee, S.-H.; Li, J.; Li, Y.; Libby, J.; Liu, Z. Q.; Liventsev, D.; Lukin, P.; MacNaughton, J.; Matvienko, D.; Miyabayashi, K.; Miyata, H.; Mizuk, R.; Moll, A.; Muramatsu, N.; Mussa, R.; Nagasaka, Y.; Nakao, M.; Nayak, M.; Ng, C.; Nisar, N. K.; Nishida, S.; Nitoh, O.; Ogawa, S.; Okuno, S.; Oswald, C.; Pakhlova, G.; Park, C. W.; Park, H.; Park, H. K.; Pedlar, T. K.; Pestotnik, R.; Petrič, M.; Piilonen, L. E.; Ritter, M.; Röhrken, M.; Rostomyan, A.; Ryu, S.; Sahoo, H.; Saito, T.; Sakai, K.; Sakai, Y.; Santelj, L.; Sanuki, T.; Sato, Y.; Savinov, V.; Schneider, O.; Schnell, G.; Semmler, D.; Senyo, K.; Sevior, M. E.; Shapkin, M.; Shen, C. P.; Shibata, T.-A.; Shiu, J.-G.; Shwartz, B.; Sibidanov, A.; Simon, F.; Sohn, Y.-S.; Sokolov, A.; Solovieva, E.; Stanič, S.; Starič, M.; Steder, M.; Sumiyoshi, T.; Tamponi, U.; Tanida, K.; Tatishvili, G.; Teramoto, Y.; Tsuboyama, T.; Uchida, M.; Uehara, S.; Uglov, T.; Unno, Y.; Uno, S.; Urquijo, P.; Vahsen, S. E.; Van Hulse, C.; Vanhoefer, P.; Varner, G.; Vorobyev, V.; Wagner, M. N.; Wang, C. H.; Wang, M.-Z.; Wang, P.; Wang, X. L.; Watanabe, M.; Watanabe, Y.; Wiechczynski, J.; Williams, K. M.; Won, E.; Yabsley, B. D.; Yamaoka, J.; Yamashita, Y.; Yashchenko, S.; Yuan, C. Z.; Yusa, Y.; Zhang, C. C.; Zhang, Z. P.; Zhilich, V.; Zupanc, A.

    2013-09-01

    We search for bottomonium states in Υ(2S)→(bb¯)γ decays with an integrated luminosity of 24.7fb-1 recorded at the Υ(2S) resonance with the Belle detector at KEK, containing (157.8±3.6)×106 Υ(2S) events. The (bb¯) system is reconstructed in 26 exclusive hadronic final states composed of charged pions, kaons, protons, and KS0 mesons. We find no evidence for the state recently observed around 9975 MeV (Xbb¯) in an analysis based on a data sample of 9.3×106 Υ(2S) events collected with the CLEO III detector. We set a 90% confidence level upper limit on the branching fraction B[Υ(2S)→Xbb¯γ]×∑iB[Xbb¯→hi]<4.9×10-6, summed over the exclusive hadronic final states employed in our analysis. This result is an order of magnitude smaller than the measurement reported with CLEO data. We also set an upper limit for the ηb(1S) state of B[Υ(2S)→ηb(1S)γ]×∑iB[ηb(1S)→hi]<3.7×10-6.

  3. Effect of the Charged Higgs Bosons in the Radiative Leptonic Decays of $B^-$ and $D^-$ Mesons

    CERN Document Server

    Yang, Ji-Chong

    2015-01-01

    In this work, we study the radiative leptonic decays of $B^-$ and $D^-$ mesons in the standard model and the two-Higgs-doublet-model type II. The results are obtained using the factorization procedure, and the contribution of the order $O(\\Lambda _{\\rm QCD}\\left/m_Q\\right.)$ is included. The numerical results are calculated using the wave-function obtained in relativistic potential model. As a result, the decay mode $B\\to \\gamma \\tau \

  4. Search for Detour Transitions in the Radiative EC Decay of $^{81}$Kr

    CERN Multimedia

    Rykaczewski, K

    2002-01-01

    % IS355 \\\\ \\\\ It is proposed to produce at ISOLDE the $^{81}$Kr activity and to study its 1-st forbidden unique (1u) radiative electron-capture decay in low background conditions available in Warsaw. The intensity of the photon spectrum will be compared to predictions of the internal-bremsstrahlung theory. A question is whether an excess of the intensity will be observed, indicating the role of detour $\\gamma$/$\\beta$ transitions via intermediate virtual nuclear states, as detected already for the 1u radiative decay of $^{41}$Ca.

  5. What can radiative decays of the X(3872) teach us about its nature?

    CERN Document Server

    Guo, Feng-Kun; Kalashnikova, Yu S; Meißner, Ulf -G; Nefediev, A V

    2014-01-01

    Starting from the hypothesis that the X(3872) is a $D\\bar D^*$ molecule, we discuss the radiative decays of the X(3872) into $\\gamma J/\\psi$ and $\\gamma\\psi'$ from an effective field theory point of view. We show that radiative decays are not sensitive to the long-range structure of the X(3872). In particular, contrary to earlier claims, we argue that the experimentally determined ratio of the mentioned branching fractions is not in conflict with a wave function of the X(3872) that is dominated by the $D\\bar D^*$ hadronic molecular component.

  6. Measurement of the radiative decay width \\Gamma[\\Lambda(1520) --> \\Lambda \\gamma] with the SPHINX spectrometer

    CERN Document Server

    Antipov, Y M; Batarin, V A; Vavilov, D V; Victorov, V A; Eroshin, O V; Golovkin, S V; Gorin, Yu P; Kolganov, V Z; Kozhevnikov, A P; Konstantinov, A S; Kubarovskii, V P; Kurshetsov, V F; Landsberg, L G; Leontiev, V M; Lomkatsi, G S; Molchanov, V V; Mukhin, V A; Nilov, A F; Patalakha, D I; Petrenko, S V; Smolyankin, V T; Antipov, Yu.M.; Gorin, Yu.P.

    2004-01-01

    The radiative decay \\Lambda(1520) --> \\Lambda \\gamma was measured directly in the study of exclusive diffractive-like reaction p + N --> \\Lambda(1520) K^+ + N, \\Lambda(1520) --> \\Lambda \\gamma with the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR[\\Lambda(1520) --> \\Lambda \\gamma] = (1.02+/-0.21)x10^{-2} and \\Gamma[\\Lambda(1520) \\to \\Lambda \\gamma] = 159+/-35 keV (statistical uncertainty). The systematic uncertainty is estimated to be below 15%.

  7. Consistent Probabilistic Description of the Neutral Kaon System

    CERN Document Server

    Bernabeu, J; Villanueva-Perez, P

    2013-01-01

    The neutral Kaon system has both CP violation in the mass matrix and a non-vanishing lifetime difference in the width matrix. This leads to an effective Hamiltonian which is not a normal operator, with incompatible (non-commuting) masses and widths. In the Weisskopf-Wigner Approach (WWA), by diagonalizing the entire Hamiltonian, the unphysical non-orthogonal "stationary" states $K_{L,S}$ are obtained. These states have complex eigenvalues whose real (imaginary) part does not coincide with the eigenvalues of the mass (width) matrix. In this work we describe the system as an open Lindblad-type quantum mechanical system due to Kaon decays. This approach, in terms of density matrices for initial and final states, provides a consistent probabilistic description, avoiding the standard problems because the width matrix becomes a composite operator not included in the Hamiltonian. We consider the dominant-decay channel to two pions, so that one of the Kaon states with definite lifetime becomes stable. This new approa...

  8. Induced polarization of Λ(1116) in kaon electroproduction with CLAS

    Science.gov (United States)

    Gabrielyan, Marianna; Raue, Brian; Carman, Daniel S.; Park, Kijun

    2013-10-01

    The CLAS Collaboration is using the p(e,e'K+p)π- reaction to perform a measurement of the induced polarization of the electroproduced Λ(1116). The parity-violating weak decay of the Λ into p&pgr- (64%) allows extraction of the recoil polarization of the Λ. This study uses the CEBAF Large Acceptance Spectrometer (CLAS) to detect the scattered electron, the kaon, and the decay proton. CLAS allows for a large kinematic acceptance with 0.8 ≤ Q2 ≤ 3.5 GeV2, 1.6 ≤ W ≤ 3.0 GeV, as well as the kaon scattering angle. In this experiment a 5.5 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. The goal is to map out the kinematic dependencies for this polarization observable to provide new constraints for theoretical models of the electromagnetic production of kaon-hyperon final states. Along with previously published photo- and electro-production cross sections and polarization observables from CLAS, SAPHIR, and GRAAL, these data are needed in a coupled-channel analysis to identify previously unobserved s-channel resonances.

  9. Probing CPT in transitions with entangled neutral kaons

    CERN Document Server

    Bernabeu, J; Villanueva-Perez, P

    2015-01-01

    In this paper we present a novel CPT symmetry test in the neutral kaon system based, for the first time, on the direct comparison of the probabilities of a transition and its CPT reverse. The required interchange of "in" $\\leftrightarrow$ "out" states for a given process is obtained exploiting the Einstein-Podolsky-Rosen correlations of neutral kaon pairs produced at a $\\phi$-factory. The observable quantities have been constructed by selecting the two semileptonic decays for flavour tag, the $\\pi\\pi$ and $3\\pi^0$ decays for CP tag and the time orderings of the decay pairs. The interpretation in terms of the standard Weisskopf-Wigner approach to this system, directly connects CPT violation in these observables to the violating $\\Re\\delta$ parameter in the mass matrix of $K^0$-$\\bar{K^0}$, a genuine CPT violating effect independent of $\\Delta \\Gamma$ and not requiring the decay as an essential ingredient. Possible spurious effects induced by CP violation in the decay and/or a violation of the $\\Delta S= \\Delta...

  10. KTAG: The Kaon Identification Detector for CERN experiment NA62

    Science.gov (United States)

    Fry, J. R.

    2016-07-01

    In the study of ultra-rare kaon decays, CERN experiment NA62 exploits an unseparated monochromatic (75 GeV/c) beam of charged particles of flux 800 MHz, of which 50 MHz are K+. Kaons are identified with more than 95% efficiency, a time resolution of better than 100 ps, and misidentification of less than 10-4 using KTAG, a differential, ring-focussed, Cherenkov detector. KTAG utilises 8 sets of 48 Hamamatsu PMTs, of which 32 are of type 9880 and 16 of type 7400, with signals fed directly to the differential inputs of NINO front-end boards and then to TDC cards within the TEL62 system. Leading and trailing edges of the PMT signal are digitised, enabling slewing corrections to be made, and a mean hit rate of 5 MHz per PMT is supported. The electronics is housed within a cooled and insulated Faraday cage with environmental monitoring capabilities.

  11. Spin-flip processes and radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers

    Science.gov (United States)

    Slobodeniuk, A. O.; Basko, D. M.

    2016-09-01

    We perform a theoretical study of radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers. This decay necessarily involves an electronic spin flip. The intrinsic decay mechanism due to interband spin-flip dipole moment perpendicular to the monolayer plane, gives a rate about 100-1000 times smaller than that of bright excitons. However, we find that this mechanism also introduces an energy splitting due to a local field effect, and the whole oscillator strength is contained in the higher-energy component, while the lowest-energy state remains dark and needs an extrinsic spin-flip mechanism for the decay. Rashba effect due to a perpendicular electric field or a dielectric substrate, gives a negligible radiative decay rate (about 107 times slower than that of bright excitons). Spin flip due to Zeeman effect in a sufficiently strong in-plane magnetic field can give a decay rate comparable to that due to the intrinsic interband spin-flip dipole.

  12. Exclusive radiative b-decays in the light-cone QCD sum rule approach

    CERN Document Server

    Ali, A; Simma, H

    1994-01-01

    We carry out a detailed study of exclusive radiative rare $B$-decays in the framework of the QCD sum rules on the light cone, which combines the traditional QCD sum rule technique with the description of final state vector mesons in terms of the light-cone wave functions of increasing twist. The decays considered are: $B_{u,d} \\to K^* +\\gamma, B_{u,d}\\to \\rho+\\gamma, B_d\\to \\omega+\\gamma$ and the corresponding decays of the $B_s$ mesons, $B_s\\to \\phi+\\gamma$ and $B_s\\to K^*+\\gamma$. Based on our estimate of the transition form factor $F_1^{B \\to K^*\\pg}(0) =0.32\\pm0.05$, we find for the branching ratio $BR(B \\to K^* + \\gamma) = (4.8\\pm 1.5)\\times 10^{-5}$, which is in agreement with the observed value measured by the CLEO collaboration. We present detailed estimates for the ratios of the radiative decay form factors, which are then used to predict the rates for the exclusive radiative B-decays listed above. This in principle allows the extraction of the CKM matrix element $|V_{td}|$ from the penguin-dominated...

  13. Bottomonium States in Radiative Y(2S) Decays

    CERN Document Server

    Sandilya, S

    2014-01-01

    A study of various bottomonium states, in Y(2S)-> gamma (b b-bar) decays, reconstructed exclusively in 26 hadronic final states is presented. The study is performed using a data sample recorded at the Y(2S) resonance with the Belle detector at KEKB, that contains 157.8 X 10^6 Y(2S) events. The chi_{bJ}(1P) states are found with their masses being consistent with the world average values. We find no evidence for the state claimed to have been observed around 9975 MeV/c^{2} in an analysis based on a data sample of 9.3 X 10^6 Y(2S) events collected with the CLEO~III detector, and place an upper limit an order of magnitude lower than the latter result. In the same study, the eta_{b}(1S) state is also searched for.

  14. Radiative decays of the Sigma0(1385) and Lambda(1520) hyperons

    Energy Technology Data Exchange (ETDEWEB)

    Simon Taylor; Gordon Mutchler; CLAS Collaboration

    2005-03-01

    The electromagnetic decays of the {Sigma}{sup 0}(1385) and {Lambda}(1520) hyperons were studied in photon-induced reactions {gamma} p {yields} K{sup +} {Lambda}(1116){gamma} in the CLAS detector at the Thomas Jefferson National Accelerator Facility. We report the first observation of the radiative decay of the {Sigma}{sup 0}(1385) and a measurement of the {Lambda}(1520) radiative decay width. For the {Sigma}{sup 0}(1385) {yields} {Lambda}(1116){gamma} transition, we measured a partial width of 479 {+-} 120(stat){sub -100}{sup +81}(sys) keV, larger than all of the existing model predictions. For the {Lambda}(1520) {yields} {Lambda}(1116){gamma} transition, we obtained a partial width of 167 {+-} 43(stat){sub -12}{sup +26}(sys) keV.

  15. Radiative decays of the Sigma0(1385) and Lambda(1520) hyperons

    CERN Document Server

    Taylor, S; Schumacher, R A; Todor, L; Adams, G; Anciant, E; Anghinolfi, M; Asavapibhop, B; Audit, G; Auger, T; Avakian, H; Bagdasaryan, H; Ball, J P; Barrow, S; Battaglieri, M; Beard, K; Bektasoglu, M; Bellis, M; Berman, Barry L; Bianchi, N; Biselli, A S; Boiarinov, S; Bonner, B E; Bouchigny, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Butuceanu, C; Calarco, J R; Carman, D S; Carnahan, B; Cetina, C; Ciciani, L; Cole, P L; Coleman, A; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J P; De Sanctis, E; De Vita, R; Degtyarenko, P V; Denizli, H; Dennis, L; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Doughty, D C; Dragovitsch, P; Dugger, M; Dytman, S; Eckhause, M; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Eugenio, P; Fatemi, R; Feuerbach, R J; Ficenec, J; Forest, T A; Funsten, H; Gaff, S J; Gai, M; Gavalian, G; Gilad, S; Gilfoyle, G P; Giovanetti, K L; Girard, P; Gordon, C I O; Griffioen, K; Guidal, M; Guillo, M R; Guo, L; Gyurjyan, V; Hadjidakis, C; Hakobyan, R S; Hardie, J; Heddle, D; Heimberg, P; Hersman, F W; Hicks, K; Hicks, R S; Holtrop, M; Hu, J; Hyde-Wright, C E; Ilieva, Y; Ito, M M; Jenkins, D; Joo, K; Kelley, J H; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Klusman, M; Kossov, M; Kramer, L H; Kuang, Y; Kuhn, S E; Lachniet, J; Laget, J M; Lawrence, D; Ji Li; Lukashin, K; Manak, J J; Marchand, C; McAleer, S; McCarthy, J; Mecking, B A; Mehrabyan, S S; Melone, J J; Mestayer, M D; Meyer, C A; Mikhailov, K; Minehart, R C; Mirazita, M; Miskimen, R; Morand, L; Morrow, S A; Muccifora, V; Müller, J; Napolitano, J; Nasseripour, R; Nelson, S O; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Brien, J T; O'Rielly, G V; Osipenko, M; Park, K; Pasyuk, E A; Peterson, G; Philips, S A; Pivnyuk, N; Pocanic, D; Pogorelko, O I; Polli, E; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Quinn, B; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Ronchetti, F; Rossi, P; Rowntree, D; Rubin, P D; Sabatie, F; Sabourov, K; Salgado, C; Santoro, J P; Sapunenko, V; Serov, V S; Shafi, A; Sharabyan, Yu G; Shaw, J; Simionatto, S; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Spraker, M; Stavinsky, A V; Stepanyan, S; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tedeschi, D J; Thoma, U; Thompson, R; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weisberg, A; Weller, H; Weygand, D P; Whisnant, C S; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zhang, B; Zhao, J; Zhou, Z

    2005-01-01

    The electromagnetic decays of the Sig0(1385) and Lambda(1520) hyperons were studied in photon-induced reactions gamma p -> K+ Lambda(1116)gamma in the CLAS detector at the Thomas Jefferson National Accelerator Facility. We report the first observation of the radiative decay of the Sig0(1385) and a measurement of the Lambda(1520) radiative decay width. For the Sig0(1385) -> Lambda(1116)gamma transition, we measured a partial width of 479+/-120(stat)+81-100(sys) keV, larger than all of the existing model predictions. For the Lambda(1520) -> Lambda(1116)gamma transition, we obtained a partial width of 167+/-43(stat)+26-12(sys) keV.

  16. Study of the radiative decay phi to a0(980) gamma with the KLOE detector

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bocci, V; Bossi, F; Branchini, P; Caloi, R; Campana, P; Capon, G; Capussela, T; Ceradini, F; Chi, S; Chiefari, G; Ciambrone, P; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Falco, S; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Finocchiaro, G; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Incagli, M; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Scuri, F; Sfiligoi, I; Spadaro, T; Testa, M; Tortora, L; Valente, P; Valeriani, B; Venanzoni, G; Versaci, R; Xu, G

    2007-01-01

    A sample of 1.25x10^9 phi decays, collected with the KLOE detector at the Frascati phi-factory DAFNE at center of mass energy ~ Mphi, has been used to study the radiative decay phi to eta pi0 gamma. This decay is dominated by phi to a0(980) gamma. Two decay chains, corresponding to eta to gamma gamma and eta to pi+ pi- pi0, have been selected. We found respectively: Br(phi to eta pi0 gamma)=(6.92 +/- 0.10 (stat.) +/- 0.20 (syst.))x10^(-5) and (7.19 +/- 0.17 (stat.) +/- 0.24 (syst.))x 10 ^(-5). The eta pi0 invariant mass distributions have been fitted to obtain the relevant a0(980) parameters.

  17. First Experimental Study of Photon Polarization in Radiative B-s(0) Decays

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Andreassi, G.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Archilli, F.; d'Argent, P.; Romeu, J. Arnau; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Babuschkin, I.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baker, S.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Baszczyk, M.; Batozskaya, V.; Batsukh, B.; Battista, V.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Betti, F.; Bettler, M. -O.; van Beuzekom, M.; Bezshyiko, I.; Bifani, S.; Billoir, P.; Bird, T.; Birnkraut, A.; Bitadze, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Boettcher, T.; Bondar, A.; Bondar, N.; Bonivento, W.; Borgheresi, A.; Borghi, S.; Borisyak, M.; Borsato, M.; Bossu, F.; Boubdir, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Buchanan, E.; Burr, C.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Camboni, A.; Campana, P.; Perez, D. Campora; Perez, D. H. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chatzikonstantinidis, G.; Chefdeville, M.; Cheung, S. -F.; Chobanova, V.; Chrzaszcz, M.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombs, G.; Coquereau, S.; Corti, G.; Corvo, M.; Sobral, C. M. Costa; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Da Cunha Marinho, F.; Dall'Occo, E.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Aguiar Francisco, O.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Serio, M.; De Simone, P.; Dean, C. -T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Demmer, M.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Dordei, F.; Dorigo, M.; Suarez, A. Dosil; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dungs, K.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Deleage, N.; Easo, S.; Ebert, M.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Farley, N.; Farry, S.; Fay, R.; Fazzini, D.; Ferguson, D.; Fernandez Albor, V.; Fernandez Prieto, A.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fini, R. A.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fleuret, F.; Fohl, K.; Fontana, M.; Fontanelli, F.; Forshaw, D. C.; Forty, R.; Lima, V. Franco; Frei, C.; Furfaro, E.; Farber, C.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Garcia Martin, L. M.; Garcia Pardinas, J.; Tico, J. Garra; Garrido, L.; Garsed, P. J.; Gascon, D.; Gaspar, C.; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Giani, S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gizdov, K.; Gligorov, V. V.; Golubkov, D.; Golutvin, A.; Gorelov, I. V.; Gotti, C.; Gandara, M. Grabalosa; Graciani Diaz, R.; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Griffith, P.; Grillo, L.; Cazon, B. R. Gruberg; Grunberg, O.; Gushchin, E.; Guz, Yu.; Gys, T.; Gobel, C.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hatch, M.; He, J.; Head, T.; Heister, A.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Hess, M.; Hicheur, A.; Hill, D.; Hombach, C.; Hopchev, H.; Hulsbergen, W.; Humair, T.; Hushchyn, M.; Hutchcroft, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jalocha, J.; Jans, E.; Jawahery, A.; Jiang, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Kariuki, J. M.; Karodia, S.; Kecke, M.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khairullin, E.; Khanji, B.; Khurewathanakul, C.; Kirn, T.; Klaver, S.; Klimaszewski, K.; Koliiev, S.; Kolpin, M.; Komarov, I.; Koppenburg, P.; Kosmyntseva, A.; Kozachuk, A.; Kozeiha, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krokovny, P.; Krzemien, W.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kuonen, A. K.; Kurek, K.; Kvaratskheliya, T.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J. -P.; Leflat, A.; Lefrancois, J.; Lefevre, R.; Lemaitre, F.; Lemos Cid, E.; Leroy, O.; Lesiak, T.; Leverington, B.; Likhomanenko, T.; Lindner, R.; Linn, C.; Lionetto, F.; Loh, D.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Lusiani, A.; Lyu, X.; Machefert, F.; Maciuc, F.; Maev, O.; Maguire, K.; Malde, S.; Malinin, A.; Maltsev, T.; Manca, G.; Mancinelli, G.; Manning, P.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Marks, J.; Martellotti, G.; Martinelli, M.; Martinez Santos, D.; Martinez Vidal, F.; Martins Tostes, D.; Massacrier, L. M.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; Mcnab, A.; McNulty, R.; Meadows, B.; Meier, F.; Melnychuk, D.; Merk, M.; Merli, A.; Michielin, E.; Milanes, D. A.; Minard, M. -N.; Mitzel, D. S.; Mogini, A.; Molina Rodriguez, J.; Monroy, I. A.; Monteil, S.; Morandin, M.; Morawski, P.; Morda, A.; Morello, M. J.; Moron, J.; Morris, A. B.; Mountain, R.; Muheim, F.; Mulder, M.; Mussini, M.; Mueller, J.; Mueller, K.; Mueller, V.; Naik, P.; Nakada, T.; Nandakumar, R.; Nandi, A.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen-Mau, C.; Nieswand, S.; Niet, R.; Nikitin, N.; Nikodem, T.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Oldeman, R.; Onderwater, C. J. G.; Goicochea, J. M. Otalora; Otto, A.; Owen, P.; Oyanguren, A.; Pais, P. R.; Palano, A.; Palombo, F.; Palutan, M.; Papanestis, A.; Pappagallo, M.; Pappalardo, L. L.; Parker, W.; Parkes, C.; Passaleva, G.; Pastore, A.; Patel, G. D.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Altarelli, M. Pepe; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petrov, A.; Petruzzo, M.; Olloqui, E. Picatoste; Pietrzyk, B.; Pikies, M.; Pinci, D.; Pistone, A.; Piucci, A.; Playfer, S.; Plo Casasus, M.; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Pomery, G. J.; Popov, A.; Popov, D.; Popovici, B.; Poslavskii, S.; Potterat, C.; Price, E.; Price, J. D.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Navarro, A. Puig; Punzi, G.; Qian, W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rama, M.; Ramos Pernas, M.; Rangel, M. S.; Raniuk, I.; Raven, G.; Redi, F.; Reichert, S.; dos Reis, A. C.; Remon Alepuz, C.; Renaudin, V.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Rives Molina, V.; Rodrigues, A. B.; Rodrigues, E.; Lopez, J. A. Rodriguez; Perez, P. Rodriguez; Rogozhnikov, A.; Roiser, S.; Rollings, A.; Romanovskiy, V.; Romero Vidal, A.; Ronayne, J. W.; Rotondo, M.; Ruf, T.; Ruiz Valls, P.; Saborido Silva, J. J.; Sadykhov, E.; Sagidova, N.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santimaria, M.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schael, S.; Schellenberg, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schubiger, M.; Schune, M. -H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sergi, A.; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Siddi, B. G.; Coutinho, R. Silva; Silva de Oliveira, L.; Simi, G.; Simone, S.; Sirendi, M.; Skidmore, N.; Skwarnicki, T.; Smith, I. T.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Stefko, P.; Stefkova, S.; Steinkamp, O.; Stemmle, S.; Stenyakin, O.; Stevenson, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Sutcliffe, W.; Swientek, K.; Syropoulos, V.; Szczekowski, M.; Szumlak, T.; T'Jampens, S.; Tayduganov, A.; Tekampe, T.; Tellarini, G.; Teubert, F.; van Tilburg, J.; Tilley, M. J.; Tisserand, V.; Tobin, M.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Toriello, F.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Traill, M.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tully, A.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valassi, A.; Valat, S.; Valenti, G.; Vallier, A.; Gomez, R. Vazquez; Vazquez Regueiro, P.; Vecchi, S.; van Veghel, M.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Venkateswaran, A.; Vernet, M.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Volkov, V.; Vollhardt, A.; Voneki, B.; Vorobyev, A.; Vorobyev, V.; Voss, C.; Vazquez Sierra, C.; Waldi, R.; Wallace, C.; Wallace, R.; Ward, D. R.; Wark, H. M.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wicht, J.; Wilkinson, G.; Williams, T.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wraight, K.; Wright, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Yu, J.; Yuan, X.; Yushchenko, O.; Zarebski, K. A.; Zavertyaev, M.; Zhelezov, A.; Zheng, Y.; Zhokhov, A.; Zhukov, V.; Zucchelli, S.

    2017-01-01

    The polarization of photons produced in radiative B-s(0) decays is studied for the first time. The data are recorded by the LHCb experiment in pp collisions corresponding to an integrated luminosity of 3 fb(-1) at center-of-mass energies of 7 and 8 TeV. A time-dependent analysis of the B-s(0) ->phi

  18. Role of gauge invariance in B -> V gamma radiative weak decays

    CERN Document Server

    Riazuddin, M

    2002-01-01

    The role of gauge invariance in calculating B -> V gamma radiative weak decays is clarified. It is shown that the gauge invariance severely restricts the contributions mediated by the usual weak non-leptonic Hamiltonian dominated by u and c quaks with one photon attachment. Such contributions are found to be almost negligible.

  19. Search for radiative decays of solar neutrinos during a solar eclipse

    CERN Document Server

    Giacomelli, G

    2001-01-01

    A search for possible radiative decays of solar neutrinos with emission of photons in the visible range may be performed during total solar eclipses. We discuss some results obtained from the digitized images recorded during the August 11, 1999 total solar eclipse in Romania, and report on the observations made in June 21, 2001, in Zambia.

  20. Probing lepton flavour (universality) violation at NA62 and future kaon experiments

    CERN Document Server

    Tunstall, Lewis C; D'Ambrosio, Giancarlo; Hoferichter, Martin

    2016-01-01

    Recent results from the LHC's first run have revealed intriguing departures from lepton flavour universality in the semi-leptonic decays of $B$-mesons. We discuss the complementary role that rare kaon decays can provide in testing new physics explanations of these flavour anomalies. In the framework of minimal flavour violation, we relate the chiral low-energy constants involved in $K\\to\\pi\\ell\\ell'$ and $K\\to\\ell\\ell'$ ($\\ell = \\mu \\mbox{ or } e$) with the new physics Wilson coefficients of the $b\\to s$ effective Hamiltonian. We comment on the determination of these low-energy constants at NA62 and future kaon experiments, as well as the required improvements in sensitivity necessary to test the $B$-physics anomalies in the kaon sector.

  1. ENUBET: Enhanced NeUtrino BEams from kaon Tagging

    Science.gov (United States)

    Meregaglia, A.

    2016-12-01

    A reduction of the neutrino flux uncertainty by one order of magnitude in conventional neutrino beams can be achieved monitoring the positron production in the decay tunnel originating from the Ke3 decays of charged kaons. This novel approach will be developed in the framework of the ERC ENUBET Project. In this talk we present the aims of the project and the ongoing R&D for the instrumentation of the decay tunnel. In particular, we describe a specialized shashlik calorimeter (iron-scintillator) with a compact readout based on small-area silicon photo multipliers that allows for a very effective longitudinal segmentation of the detector to enhance electron/hadron separation. The expected performance of the detector estimated from a full GEANT4 simulation of the neutrino decay tunnel are presented. We also discuss preliminary results on a prototype composed by 12 ultra compact modules exposed to pions and electrons at CERN-PS.

  2. Vector meson photoproduction studied in its radiative decay channel

    CERN Document Server

    Zhao, Q; Cole, P L; Zhao, Qiang

    2005-01-01

    We provide an analysis of vector meson photoproduction in the channel of the vector meson decaying into a pseudoscalar meson plus a photon, i.e. $V\\to P\\gamma$. It is shown that non-trivial kinematic correlations arise from the measurement of the $P\\gamma$ angular distributions in the overall c.m. system in comparison with those in the vector-meson-rest frame. In terms of the vector meson density matrix elements, the implication of such kinematic correlations in the measurement of polarization observables is discussed. For the $\\omega$ meson production, due to its relatively large branching ratios for $\\omega\\to\\pi^0\\gamma$, additional events from this channel may enrich the information about the reaction mechanism and improve the statistics of the recent measurement of polarized beam asymmetries by the GRAAL Collaboration. For $\\phi\\to \\eta\\gamma$, $\\rho\\to \\pi\\gamma$, and $K^*\\to K\\gamma$, we expect that additional information about the spin structure of the vector meson production vertex can be derived.

  3. Quasifree kaon photoproduction on nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Frank Lee; T. MART; Cornelius Bennhold; Lester Wright

    2001-12-01

    Investigations of the quasifree reaction A({gamma}, K Y)B are presented in the distorted wave impulse approximation (DWIA). For this purpose, we present a revised tree-level model of elementary kaon photoproduction that incorporates hadronic form factors consistent with gauge invariance, uses SU(3) values for the Born couplings and uses resonances consistent with multi-channel analyses. The potential of exclusive quasifree kaon photoproduction on nuclei to reveal details of the hyperon-nucleus interaction is examined. Detailed predictions for the coincidence cross section, the photon asymmetry, and the hyperon polarization and their sensitivities to the ingredients of the model are obtained for all six production channels. Under selected kinematics these observables are found to be sensitive to the hyperon-nucleus final state interaction. Some polarization observables are found to be insensitive to distortion effects, making them ideal tools to search for possible medium modifications of the elementary amplitude.

  4. Spontaneous radiative decay of translational levels of an atom near a dielectric surface

    CERN Document Server

    Le Kien, F; Kien, Fam Le

    2006-01-01

    We study spontaneous radiative decay of translational levels of an atom in the vicinity of a semi-infinite dielectric. We systematically derive the microscopic dynamical equations for the spontaneous decay process. We calculate analytically and numerically the radiative linewidths and the spontaneous transition rates for the translational levels. The roles of the interference between the emitted and reflected fields and of the transmission into the evanescent modes are clearly identified. Our numerical calculations for the silica--cesium interaction show that the radiative linewidths of the bound excited levels with large enough but not too large vibrational quantum numbers are moderately enhanced by the emission into the evanescent modes and those for the deep bound levels are substantially reduced by the surface-induced red shift of the transition frequency.

  5. Bayesian analysis for kaon photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Marsainy, T., E-mail: tmart@fisika.ui.ac.id; Mart, T., E-mail: tmart@fisika.ui.ac.id [Department Fisika, FMIPA, Universitas Indonesia, Depok 16424 (Indonesia)

    2014-09-25

    We have investigated contribution of the nucleon resonances in the kaon photoproduction process by using an established statistical decision making method, i.e. the Bayesian method. This method does not only evaluate the model over its entire parameter space, but also takes the prior information and experimental data into account. The result indicates that certain resonances have larger probabilities to contribute to the process.

  6. Renormalisation Group Flow and Kaon Condensation

    CERN Document Server

    Krippa, Boris

    2016-01-01

    Functional renormalisation group approach is applied to a system of kaons with finite chemical potential. A set of approximate flow equations for the effective couplings is derived and solved. At high scale the system is found to be at the normal phase whereas at some critical value of the running scale it undergoes the phase transition (PT) to the phase with a spontaneously broken symmetry with the kaon condensate as an order parameter. The value of the condensate turns out to be quite sensitive to the kaon-kaon scattering length.

  7. Rare radiative decays of the $B_c$ meson

    CERN Document Server

    Ju, Wan-Li; Jiang, Yue; Yuan, Han; Wang, Guo-Li

    2015-01-01

    In this paper, we study the rare radiative processes $B_c\\to D_{(s)J} ^{(*)}\\gamma$ within the Standard Model, where $D_{(s)J}^{(*)}$ stands for the meson $D_{(s)}^*$, $D_{s1}(2460,2536)$ or $D_{s2}^*(2573)$. During the investigations, we consider the contributions from the penguin, annihilation, color-suppressed and color-favored cascade diagrams. Our results show that: 1) the penguin and annihilation contributions are dominant in the branching fractions; 2) for the processes $B_c\\to D_{(s)}^{*}\\gamma$ and $B_c\\to D_{s1}(2460)\\gamma$, the effects from the color-suppressed and color-favored cascade diagrams are un-ignorable.

  8. Study of Rare Radiative B Decay to K*(1430) Meson Using the BABAR Detector

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Qinghua; /Pennsylvania U.

    2005-09-14

    Radiative B Meson decay through the b {yields} s{gamma} process has been one of the most sensitive probe of new physics beyond the Standard Model, because of its importance in understanding the phenomenon of CP violation, which is believed to be necessary to explain the excess of matter over anti-matter in our universe. The inclusive picture of the b {yields} s{gamma} process is well established; however, our knowledge of the exclusive final states in radiative B meson decays is rather limited. We have investigated one of them, the exclusive, radiative B decay to the charmless K*{sub 2}(1430) meson, in a sample of 88.5 x 10{sup 6} B{bar B} events with the BABAR detector at the PEP-II storage ring. We present a measurement of the branching fractions {Beta}(B{sup 0} {yields} K*{sub 2}(1430){sup 0}{gamma}) = (1.22 {+-} 0.25 {+-} 0.10) x 10{sup -5} and {Beta}(B{sup +} {yields} K*{sub 2}(1430){sup +}){gamma} = (1.45 {+-} 0.40 {+-} 0.15) x 10{sup -5}, where the first error is statistical and the second systematic. In addition, we have performed the first search for direct CP violation in this decay with the measured asymmetry in B{sup 0} {yields} K*{sub 2}(1430){sup 0}{gamma} of {Alpha}{sub CP} = -0.08 {+-} 0.15 {+-} 0.01.

  9. Exclusive radiative decays of W and Z bosons in QCD factorization

    Science.gov (United States)

    Grossman, Yuval; König, Matthias; Neubert, Matthias

    2015-04-01

    We present a detailed theoretical analysis of very rare, exclusive hadronic decays of the electroweak gauge bosons V = W, Z from first principles of QCD. Our main focus is on the radiative decays V → Mγ, in which M is a pseudoscalar or vector meson. At leading order in an expansion in powers of ΛQCD /m V the decay amplitudes can be factorized into convolutions of calculable hard-scattering coefficients with the leading-twist light-cone distribution amplitude of the meson M. Power corrections to the decay rates arise first at order (ΛQCD /m V ) 2 . They can be estimated in terms of higher-twist distribution amplitudes and are predicted to be tiny. We include one-loop radiative corrections to the hard-scattering coefficients and perform the resummation of large logarithms ( α s ln( m {/v 2}/ μ {0/2})) n (with μ 0 ˜ 1 GeV a typical hadronic scale) to all orders in perturbation theory. Evolution effects have an important impact both numerically and conceptually, since they reduce the sensitivity to poorly determined hadronic parameters. We present detailed numerical predictions and error estimates, which can serve as benchmarks for future precision measurements. We also present an exploratory study of the weak radiative decays Z → MW. Some of the decay modes studied here have branching ratios large enough to be accessible in the high-luminosity run of the LHC. Many of them can be measured with high accuracy at a future lepton collider. This will provide stringent tests of the QCD factorization formalism and enable novel searches for new physics.

  10. Exclusive radiative decays of W and Z bosons in QCD factorization

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, Yuval [Department of Physics, LEPP, Cornell University,Ithaca, NY 14853 (United States); König, Matthias [PRISMA Cluster of Excellence & Mainz Institute for Theoretical Physics,Johannes Gutenberg University,55099 Mainz (Germany); Neubert, Matthias [Department of Physics, LEPP, Cornell University,Ithaca, NY 14853 (United States); PRISMA Cluster of Excellence & Mainz Institute for Theoretical Physics,Johannes Gutenberg University,55099 Mainz (Germany)

    2015-04-20

    We present a detailed theoretical analysis of very rare, exclusive hadronic decays of the electroweak gauge bosons V=W,Z from first principles of QCD. Our main focus is on the radiative decays V→Mγ, in which M is a pseudoscalar or vector meson. At leading order in an expansion in powers of Λ{sub QCD}/m{sub V} the decay amplitudes can be factorized into convolutions of calculable hard-scattering coefficients with the leading-twist light-cone distribution amplitude of the meson M. Power corrections to the decay rates arise first at order (Λ{sub QCD}/m{sub V}){sup 2}. They can be estimated in terms of higher-twist distribution amplitudes and are predicted to be tiny. We include one-loop O(α{sub s}) radiative corrections to the hard-scattering coefficients and perform the resummation of large logarithms (α{sub s}ln (m{sub V}{sup 2}/μ{sub 0}{sup 2})){sup n} (with μ{sub 0}∼1 GeV a typical hadronic scale) to all orders in perturbation theory. Evolution effects have an important impact both numerically and conceptually, since they reduce the sensitivity to poorly determined hadronic parameters. We present detailed numerical predictions and error estimates, which can serve as benchmarks for future precision measurements. We also present an exploratory study of the weak radiative decays Z→MW. Some of the decay modes studied here have branching ratios large enough to be accessible in the high-luminosity run of the LHC. Many of them can be measured with high accuracy at a future lepton collider. This will provide stringent tests of the QCD factorization formalism and enable novel searches for new physics.

  11. Vacuum Cherenkov radiation and photon decay rates from generic Lorentz Invariance Violation

    CERN Document Server

    Martínez-Huerta, H

    2016-01-01

    Among the most studied approaches to introduce the breaking of Lorentz symmetry, the generic approach is one of the most frequently used for phenomenology, it converges on the modification of the free particle dispersion relation. Using this approach in the photon sector, we have calculated the squared probability amplitude for vacuum Cherenkov radiation and photon decay by correcting the QED coupling at tree level and first order in LIV parameters. For the lower order energy correction we calculate the emission and decay rate for each process.

  12. Radiative decays $V\\rightarrow P\\gamma^{*}$ in the instant form of relativistic quantum mechanics

    CERN Document Server

    Krutov, Alexander; Troitsky, Vadim

    2016-01-01

    Calculations of form factor for the radiative decays $V\\rightarrow P\\gamma^{*}$ process are performed in the framework of an instant form of relativistic quantum mechanics. The electromagnetic current operator for this decay is constructed. The transition form factor is obtained in the so called relativistic modified impulse approximation (MIA). The current operator satisfies the conditions of Lorentz-covariance and current conservation in MIA. The results of the calculations are compared with the analogous results in the light-front dynamics and in the model of vector meson dominance

  13. ANISOTROPIC RADIATIVE DECAY OF InP SELF-ASSEMBLED QUANTUM DOTS

    OpenAIRE

    1998-01-01

    Strong optical anisotropy of the photoluminescence (PL) spectra and time resolvedPL spectra is observed in InP self-assembled quantum dots (SADs) embedded inGaInP matrix. From the TEM study, the origin of the optical anisotropy appearsto be due to the formation of composition modulation planes in GaInP matrix.We also studied the size dependence of the radiative decay time. In the vicinityof the PL peak from InP SADs, slowdown of the PL decay time was observed ondecreasing the detection energy...

  14. Electromagnetic transition form factor and radiative corrections in decays of neutral pions

    Directory of Open Access Journals (Sweden)

    Husek Tomáš

    2016-01-01

    Full Text Available We briefly summarize experimental and theoretical results on the rare decay π0 → e+e−. The notorious 3.3σ discrepancy between the SM prediction and the experimental value provided by KTeV collaboration is discussed in the view of a complete set of NLO QED radiative corrections. We also present the Two-Hadron Saturation (THS scenario for the PVV correlator and apply it to the decay under discussion. The discrepancy then reduces down to 1.8σ.

  15. Radiative decays of $1^{++}$ heavy mesons in the covariant light-front approach

    CERN Document Server

    Shi, Yan-Liang

    2016-01-01

    We calculate the predicted width for the radiative decay of a $1^{++}$ heavy meson via the channel $1^{++} \\to 1^{--} +\\gamma$ in the covariant light-front quark model. Specifically, we compute the decay widths for $\\chi_{c1}(1P) \\to J/\\psi + \\gamma$ and $\\chi_{b1}(nP) \\to \\Upsilon(n'S) + \\gamma$. The results are compared with experimental data and with predictions from calculations based on nonrelativistic models and their extensions to include relativistic effects.

  16. Nanoantenna enhanced radiative and anisotropic decay rates in monolayer-quantum dots

    CERN Document Server

    Tripathi, Laxmi Narayan; Johns, Ben; Basu, Jaydeep Kumar

    2016-01-01

    Nanoantenna enhanced ultrafast emission from colloidal quantum dots as quantum emitters is required for fast quantum communications. On chip integration of such devices require a scalable and high throughput technology. We report self-assembly lithography technique of preparing hybrid of gold-nanorods antenna over a com- pact CdSe quantum dot monolayer. We demonstrate resonant and off resonant gold nanorod antenna enhanced radiative and anisotropic decay. Extensive simulations explain the mechanism of the decay rates and the role of antenna in both random and a compact monolayer of quantum dots. The study could find applications in quantum dots display and quantum communications devices.

  17. CP violation and Kaon weak matrix elements from Lattice QCD

    CERN Document Server

    Garron, Nicolas

    2015-01-01

    In this short review, I present the recent lattice computations of kaon weak matrix elements relevant to $K \\to \\pi\\pi$ decays and neutral kaon mixing. These matrix elements are key to the theoretical determination of the CP violation parameters $\\epsilon$ and $\\epsilon'$ . Impressive progress have been achieved recently, in particular the first realistic computation of $\\epsilon'/\\epsilon$ with physical kinematics has been reported in [1]. The novelty is the $\\Delta I = 1/2$ channel, whereas the $\\Delta I = 3/2$ contribution is now computed at several values of the lattice spacing and extrapolated to the continuum limit. I will also present the status of $B_K$ and discuss its error budget, with a particular emphasis on the perturbative error. Finally I will review the matrix elements of neutral kaon mixing beyond the standard model and will argue that the discrepancy observed by different collaborations could be explained by the renormalisation procedure of the relevant four-quark operators.

  18. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is taken from one of CERN's bubble chambers and shows the decay of a positive kaon in flight. The decay products of this kaon can be seen spiraling in the magnetic field of the chamber. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that has been heated to boiling point.

  19. Effect of the charged Higgs bosons in the radiative leptonic decays of B- and D- mesons

    Science.gov (United States)

    Yang, Ji-Chong; Yang, Mao-Zhi

    2016-12-01

    In this work, we study the radiative leptonic decays of B- and D- mesons in the Standard Model (SM) and two-Higgs-doublet-model (2HDM) Type II. The results are obtained using the factorization procedure, and the contribution of the order O(ΛQCD/mQ) is included. The numerical results are calculated using the wave function obtained in relativistic potential model. As a result, the decay mode B → γτντ is found to be sensitive to the effect of the charged Higgs boson. Using the constraint on the free parameters of 2HDM given in previous works, we find the contribution of the charged Higgs boson in the decay mode B → γτντ can be as large as about 13%.

  20. Observation of tree-level B decays with ss production from gluon radiation.

    Science.gov (United States)

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Ricciardi, S; Roethel, W; Wilson, F F; Aleksan, R; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Hryn'ova, T; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2008-05-02

    We report on our search for decays proceeding via a tree-level b-->c quark transition in which a gluon radiates into an ss[over ] pair. We present observations of the decays B;{-}-->D_{s};{+}K;{-}pi;{-} and B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and evidence for B;{-}-->D_{s};{+}K;{-}K;{-} and set upper limits on the branching fractions for B[over ];{0}-->D_{s};{+}K_{S};{0}pi;{-} and B;{-}-->D_{s};{+}K;{-}K;{-} using 383x10;{6} Upsilon(4S)-->BB[over ] events collected by the BABAR detector at SLAC. We present evidence that the invariant mass distributions of D_{s};{+}K;{-} pairs from B;{-}-->D_{s};{+}K;{-}pi;{-} decays are inconsistent with the phase-space model, suggesting the presence of charm resonances lying below the D_{s};{+}K;{-} threshold.

  1. Report on strangeness photoproduction experiments performed with the Neutral Kaon Spectrometer 2

    CERN Document Server

    Beckford, B; Doi, D; Fujibayashi, J; Fujii, T; Fujii, Y; Futatsukawa, K; Gogami, T; Hashimoto, O; Han, Y C; Hirose, K; Hirose, S; Honda, R; Honda, R; Hosomi, K; Iguchi, A; Ishikawa, T; Kanda, H; Kaneta, M; Kaneko, Y; Kato, S; Kawama, D; Kawasaki, T; Kiyokawa, S; Koike, T; Maeda, K; Makabe, K; Maruyama, N; Matsubara, M; Miwa, K; Miyagi, Y; Nagao, S; Nakamura, S N; Okuyama, A; Shirotori, K; Sugihara, K; Suzuki, K; Tamae, T; Tamura, H; Terada, N; Tsukada, K; Yagi, K; Yamamoto, F; Yamamoto, T O; Yamazaki, H; Yonemoto, Y

    2012-01-01

    An experiment designed to investigate the strangeness photoproduction process using a tagged photon beam in the energy range of 0.90 -1.08 GeV incident on a liquid deuterium target was successfully performed. The purpose of the experiment was to measure the production of neutral kaons and the lambda particles on a deuteron. The generation of photo produced particles was verified by the measurement of their decayed charged particles in the Neutral Kaon Spectrometer 2. The reconstructed invariant mass distributions were achieved by selecting events where two or more particles tracks were identified. Preliminary results are presented here.

  2. Simulation of decay processes and radiation transport times in radioactivity measurements

    Science.gov (United States)

    García-Toraño, E.; Peyres, V.; Bé, M.-M.; Dulieu, C.; Lépy, M.-C.; Salvat, F.

    2017-04-01

    The Fortran subroutine package PENNUC, which simulates random decay pathways of radioactive nuclides, is described. The decay scheme of the active nuclide is obtained from the NUCLEIDE database, whose web application has been complemented with the option of exporting nuclear decay data (possible nuclear transitions, branching ratios, type and energy of emitted particles) in a format that is readable by the simulation subroutines. In the case of beta emitters, the initial energy of the electron or positron is sampled from the theoretical Fermi spectrum. De-excitation of the atomic electron cloud following electron capture and internal conversion is described using transition probabilities from the LLNL Evaluated Atomic Data Library and empirical or calculated energies of released X rays and Auger electrons. The time evolution of radiation showers is determined by considering the lifetimes of nuclear and atomic levels, as well as radiation propagation times. Although PENNUC is designed to operate independently, here it is used in conjunction with the electron-photon transport code PENELOPE, and both together allow the simulation of experiments with radioactive sources in complex material structures consisting of homogeneous bodies limited by quadric surfaces. The reliability of these simulation tools is demonstrated through comparisons of simulated and measured energy spectra from radionuclides with complex multi-gamma spectra, nuclides with metastable levels in their decay pathways, nuclides with two daughters, and beta plus emitters.

  3. Results and prospects on kaon physics with the NA62 experiment at CERN

    CERN Document Server

    Mirra, M

    2015-01-01

    The measurement of the ratio of the rates of leptonic kaon decays performed by NA48/2 and NA62 ( R K phase) experiments is presented, together with the description of the NA62 experiment that will start collecting data in 2015 at the CERN SPS with the main goal of measuring the branching ratio(BR) of the rare decay K + → π + ν ̄ ν with a precision of 10%

  4. A Green's function method for handling radiative effects on false vacuum decay

    CERN Document Server

    Garbrecht, Bjorn

    2015-01-01

    We introduce a Green's function method for handling radiative effects on false vacuum decay. In addition to the usual thin-wall approximation, we achieve further simplification by treating the bubble wall in the planar limit. As an application, we take the $\\lambda\\phi^4$ theory, extended with $N$ additional heavier scalars, wherein we calculate analytically both the functional determinant of the quadratic fluctuations about the classical soliton configuration as well as the first correction to the soliton configuration itself.

  5. Search for possible solar neutrino radiative decays during total solar eclipses

    CERN Document Server

    Cecchini, S; Giacomelli, G; Giacomelli, R; Popa, V

    2006-01-01

    Total solar eclipses (TSEs) offer a good opportunity to look for photons produced in possible radiative decays of solar neutrinos. In this paper we briefly review the physics bases of such searches as well as the existing limits on the neutrino proper lifetimes obtained by such experiments. We the report on the observations performed in occasion of the 29 March 2006 TSE, from Waw an Namos, Libya.

  6. Radiative corrections to all charge assignments of heavy quark baryon semileptonic decays

    CERN Document Server

    Martínez, A; García, A; Flores-Mendieta, R; Flores-Mendieta, Ruben

    2002-01-01

    In semileptonic decays of spin-1/2 baryons containing heavy quarks up to six charge assignments for the baryons and lepton are possible. We show that the radiative corrections to four of these possibilities can be directly obtained from the final results of the two possibilities previously studied. There is no need to recalculate integrals over virtual or real photon momentum or any traces.

  7. Monte Carlo study of the measurement of the Michel parameters in the radiative decay of the τ at Belle

    Science.gov (United States)

    Shimizu, N.; Aihara, H.; Epifanov, D.

    2016-07-01

    Michel parameters are kinematic values defined as bilinear combinations of the coupling terms in the general matrix element of the Fermi interaction where all possible Lorentz-invariant scalar, vector and tensor terms are included. The leptonic τ decays provide an excellent laboratory in which to measure the Michel parameters. Any deviation of these parameters from the Standard Model expectation would indicate New Physics. Two Michel parameters, η bar and ξκ, can only be measured in the radiative leptonic decay. These parameters have previously been measured in the radiative decay of the muon but as yet have not been measured in τ decays. We report the results of a feasibility study of the measurement of η bar and ξκ in radiative leptonic τ decays at Belle and Belle II.

  8. $K_S$ semileptonic decays and test of $\\mathcal{CPT}$ symmetry with the KLOE detector

    CERN Document Server

    Kamińska, D

    2015-01-01

    Study of semileptonic decays of neutral kaons allows to perform a test of discrete symmetries, as well as basic principles of the Standard Model. In this paper a general review on dependency between charge asymmetry constructed for semileptonic decays of short- and long-lived kaons and $\\mathcal{CPT}$ symmetry is given.

  9. Dark Radiation or Warm Dark Matter from long lived particle decays in the light of Planck

    Energy Technology Data Exchange (ETDEWEB)

    Di Bari, Pasquale, E-mail: P.Di-Bari@soton.ac.uk; King, Stephen F., E-mail: S.F.King@soton.ac.uk; Merle, Alexander, E-mail: A.Merle@soton.ac.uk

    2013-07-09

    Although Planck data supports the standard ΛCDM model, it still allows for the presence of Dark Radiation corresponding up to about half an extra standard neutrino species. We propose a scenario for obtaining a fractional “effective neutrino species” from a thermally produced particle which decays into a much lighter stable relic plus standard fermions. At lifetimes much longer than ∼1 s, both the relic particles and the non-thermal neutrino component contribute to Dark Radiation. By increasing the stable-to-unstable particle mass ratio, the relic particle no longer acts as Dark Radiation but instead becomes a candidate for Warm Dark Matter with mass O(1 keV–100 GeV). In both cases it is possible to address the lithium problem.

  10. External meeting - Geneva University: Semileptonic and Radiative B-meson decays

    CERN Multimedia

    2007-01-01

    GENEVA UNIVERSITY ECOLE DE PHYSIQUE Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 - Tél : 022 379 62 73 - Fax: 022 379 69 92 Wednesday 4 April 2007 PARTICLE PHYSICS SEMINAR at 17:00 - Stückelberg Auditorium Semileptonic and Radiative B-meson decays by Dr Antonio Limosani / K2K, Japon The success of the B Factories at KEK and SLAC has furthered our knowledge of CP violation, a necessary ingredient for the creation of a matter-dominanted universe. Ever increasing data samples has ushered in a new era of precision CP measurements, in which the unitarity of the Cabibbo-Kobayashi-Maskawa matrix is examined for signs of New Physics. One of the crucial pieces of information, surprisingly, comes not from CP violation but from studies of semileptonic decays of the B mesons. I will discuss how various measurements of semileptonic and radiative B decays combine together to provide a precision measurement of the CKM matrix element |Vcb| and to determine the value of s...

  11. Radiative Decays of the $X(3872)$ in the Charmonium-Molecule Hybrid Picture

    CERN Document Server

    Takeuchi, Sachiko; Shimizu, Kiyotaka

    2016-01-01

    The X(3872) radiative decay is discussed by employing a two-meson multichannel model with the charmonium components, which explains many of the other observed features of X(3872). We have found that the ratio of the branching fractions of the X(3872) radiative decays, $R_\\gamma =\\text{Br}(X(3872)\\rightarrow\\psi(2S)\\gamma)$ / Br$(X(3872)\\rightarrow J/\\psi\\gamma)$, is 1.1 $\\sim$ 3.4 if one assumes that the decay occurs only from the charmonium components. The invariant mass spectra of $cc^{bar}$($2P$)$\\rightarrow J/\\psi \\gamma$ and $cc^{bar}$($2P$)$\\rightarrow \\psi(2S) \\gamma$ are also investigated. It is found that an enhancement appears at around $E\\sim 3960$ MeV in the $\\psi(2S) \\gamma$ spectrum but not in the $J/\\psi\\gamma$ spectrum. This corresponds to the missing $cc^{bar}$($2P$) pole which was predicted by the quark models but has not been observed due to the coupling to the $DD^{bar}$ states. We argue that the fluctuation seen in the experimental $\\psi(2S) \\gamma$ spectrum reported by LHCb may correspon...

  12. Measurement of the radiative decay of polarized muons in the MEG experiment

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, A.M.; Bemporad, C.; Cei, F.; D' Onofrio, A.; Dussoni, S.; Galli, L.; Grassi, M.; Nicolo, D.; Sergiampietri, F.; Signorelli, G.; Tenchini, F. [INFN, Sezione di Pisa (Italy); Dipartimento di Fisica, Pisa Univ. (Italy); Bao, Y.; Hildebrandt, M.; Kettle, P.R.; Mtchedlishvili, A.; Papa, A.; Ritt, S. [Paul Scherrer Institut PSI, Villigen (Switzerland); Baracchini, E. [ICEPP, The University of Tokyo, Tokyo (Japan); INFN, Laboratori Nazionali di Frascati, Frascati, Rome (Italy); Berg, F.; Hodge, Z.; Rutar, G. [Paul Scherrer Institut PSI, Villigen (Switzerland); Swiss Federal Institute of Technology ETH, Zurich (Switzerland); Biasotti, M.; De Gerone, M.; Gatti, F.; Pizzigoni, G. [INFN, Sezione di Genova (Italy); Dipartimento di Fisica, Genoa Univ. (Italy); Boca, G.; Cattaneo, P.W.; De Bari, A.; Rossella, M. [INFN, Sezione di Pavia (Italy); Dipartimento di Fisica, Pavia Univ. (Italy); Cavoto, G.; Graziosi, A.; Piredda, G.; Ripiccini, E.; Voena, C. [INFN, Sezione di Roma (Italy); Dipartimento di Fisica, ' ' Sapienza' ' Univ. Rome (Italy); Chiarello, G.; Chiri, C.; Grancagnolo, F.; Panareo, M.; Pepino, A.; Tassielli, G.F. [INFN, Sezione di Lecce (Italy); Dipartimento di Matematica e Fisica, Salento Univ. Lecce (Italy); Fujii, Y.; Iwamoto, T.; Kaneko, D.; Mori, Toshinori; Nakaura, S.; Nishimura, M.; Ogawa, S.; Ootani, W.; Sawada, R.; Uchiyama, Y.; Yoshida, K. [ICEPP, The University of Tokyo, Tokyo (Japan); Grigoriev, D.N. [Budker Institute of Nuclear Physics of Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation); Novosibirsk State Technical University, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Haruyama, T.; Mihara, S.; Nishiguchi, H.; Yamamoto, A. [KEK, High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Ieki, K. [Paul Scherrer Institut PSI, Villigen (Switzerland); ICEPP, The University of Tokyo, Tokyo (Japan); Ignatov, F.; Khazin, B.I.; Popov, A.; Yudin, Yu.V. [Budker Institute of Nuclear Physics of Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Kang, Tae Im; Lim, G.M.A.; Molzon, W.; You, Z. [University of California, Irvine, CA (United States); Khomutov, N.; Korenchenko, A.; Kravchuk, N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Renga, F. [Paul Scherrer Institut PSI, Villigen (Switzerland); INFN, Sezione di Roma (Italy); Dipartimento di Fisica, ' ' Sapienza' ' Univ. Rome (Italy); Venturini, M. [INFN Sezione di Pisa (Italy); Dipartimento di Fisica, Pisa Univ. (Italy); Scuola Normale Superiore, Pisa (Italy); Collaboration: The MEG Collaboration

    2016-03-15

    We studied the radiative muon decay μ{sup +} → e{sup +}νanti νγ by using for the first time an almost fully polarized muon source. We identified a large sample (∝13,000) of these decays in a total sample of 1.8 x 10{sup 14} positive muon decays collected in the MEG experiment in the years 2009-2010 and measured the branching ratio B(μ{sup +} → eνanti νγ) = (6.03 ± 0.14(stat.) ± 0.53(sys.)) x 10{sup -8} for E{sub e} > 45 MeV and E{sub γ} > 40 MeV, consistent with the Standard Model prediction. The precise measurement of this decay mode provides a basic tool for the timing calibration, a normalization channel, and a strong quality check of the complete MEG experiment in the search for μ{sup +} → e{sup +}γ process. (orig.)

  13. Characterizing the decay of ancient Chinese silk fabrics by microbeam synchrotron radiation diffraction.

    Science.gov (United States)

    Hermes, A C; Davies, R J; Greiff, S; Kutzke, H; Lahlil, S; Wyeth, P; Riekel, C

    2006-03-01

    Scanning synchrotron radiation microdiffraction with an approximately 1 x 1 microm(2) beam has been used as a novel method for characterizing the decay of several T'ang dynasty (618-907 AD) silk fabrics. The crystalline fraction could be visualized based on beta-sheet 210 reflection intensities, extracted by recursive peak fits from several thousand diffraction patterns recorded during mesh scans. The azimuthal width of the 210 reflection, which is related to the orientation distribution of the crystalline domains within nanofibrils and the macroscopic orientation of the fibers traversed by the beam, was found to be sensitive to the overall state of decay of the fabric. The fine structure of the histogram of azimuthal width was related to the fiber hierarchical microstructure and the fabric morphology. SAXS/WAXS analysis supports the assumption of an initial loss of the random chain network with decay. At a subsequent state of aging, decay proceeds into the nanofibrils and the silk fibers break up into even smaller fractions.

  14. Contribution of Neutron Beta Decay to Radiation Belt Pumping from High Altitude Nuclear Explosion

    Energy Technology Data Exchange (ETDEWEB)

    Marrs, R

    2002-11-13

    In 1962, several satellites were lost following high altitude nuclear tests by the United States and the Soviet Union. These satellite failures were caused by energetic electrons injected into the earth's radiation belts from the beta decay of bomb produced fission fragments and neutrons. It has been 40 years since the last high altitude nuclear test; there are now many more satellites in orbit, and it is important to understand their vulnerability to radiation belt pumping from nuclear explosions at high altitude or in space. This report presents the results of a calculation of the contribution of neutron beta decay to artificial belt pumping. For most high altitude nuclear explosions, neutrons are expected to make a smaller contribution than fission products to the total trapped electron inventory, and their contribution is usually neglected. However, the neutron contribution may dominate in cases where the fission product contribution is suppressed due to the altitude or geomagnetic latitude of the nuclear explosion, and for regions of the radiation belts with field lines far from the detonation point. In any case, an accurate model of belt pumping from high altitude nuclear explosions, and a self-consistent explanation of the 1962 data, require inclusion of the neutron contribution. One recent analysis of satellite measurements of electron flux from the 1962 tests found that a better fit to the data is obtained if the neutron contribution to the trapped electron inventory was larger than that of the fission products [l]. Belt pumping from high altitude nuclear explosions is a complicated process. Fission fragments are dispersed as part of the ionized bomb debris, which is constrained and guided by the earth's magnetic field. Those fission products that beta decay before being lost to the earth's atmosphere can contribute trapped energetic electrons to the earth's radiation belts. There has been a large effort to develop computer models for

  15. Annihilation type rare radiative $B_{(s)}\\to V\\gamma$ decays

    CERN Document Server

    Kozachuk, Anastasiya; Nikitin, Nikolai

    2016-01-01

    We obtain predictions for a number of radiative decays $B_{(s)}\\to V\\gamma$, $V$ the vector meson, which proceed through the weak-annihilation mechanism. Within the factorization approximation, we take into account the photon emission from the $B$-meson loop and from the vector-meson loop; the latter subprocesses were not considered in the previous analyses but are found to have sizeable impact on the $B_{(s)}\\to V\\gamma$ decay rate. The highest branching ratios for the weak-annihilation reactions reported here are ${\\cal B}(\\bar B^0_s\\to J/\\psi\\gamma)=1.5\\cdot 10^{-7}$ and ${\\cal B}(B^-\\to \\bar D_s^{*-}\\gamma)=1.7\\cdot 10^{-7}$, the estimated accuracy of these predictions being at the level of 20\\%.

  16. First experimental study of photon polarization in radiative $B^{0}_{s}$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Babuschkin, Igor; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Baszczyk, Mateusz; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bitadze, Alexander; Bizzeti, Andrea; Blake, Thomas; Blanc, Frederic; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel; Campora Perez, Daniel Hugo; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chobanova, Veronika; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombs, George; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Costa Sobral, Cayo Mar; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Da Cunha Marinho, Franciole; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Déléage, Nicolas; Easo, Sajan; Ebert, Marcus; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Albor, Victor; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Furfaro, Emiliano; Färber, Christian; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David

    2017-01-09

    The polarization of photons produced in radiative $B^{0}_{s}$ decays is studied for the first time. The data are recorded by the LHCb experiment in $pp$ collisions corresponding to an integrated luminosity of 3fb$^{-1}$ at center-of-mass energies of $7$ and $8$TeV. A time-dependent analysis of the $B^{0}_{s} \\to \\phi \\gamma$ decay rate is conducted to determine the parameter ${\\mathcal{A}}^\\Delta$, which is related to the ratio of right- over left-handed photon polarization amplitudes in $b \\to s \\gamma$ transitions. A value of ${\\mathcal{A}}^\\Delta=-0.98^{\\,+0.46\\,+0.23}_{\\,-0.52\\,-0.20}$ is measured. This result is consistent with the Standard Model prediction within two standard deviations.

  17. Revisiting LHC gluino mass bounds through radiative decays using MadAnalysis 5

    CERN Document Server

    Chalons, G

    2015-01-01

    The ATLAS and CMS experiments at the CERN LHC have collected about 25 inverse femtobarns (fb) of data each at the end of their 8 TeV run, and ruled out a huge swath of parameter space in the context of Minimally Supersymmetric Standard Model (MSSM). Limits on masses of the gluino have been pushed to above 1 TeV. These limits are however extremely model dependent and do not always reflect the level of exclusion. So far the limits on the gluino mass using the simplified model approach only constrained its value using its three-body decays. We show in this work that already existing ATLAS and CMS analysis can also constrain the radiative gluino decay mode and we derived improved mass limits in particular when the mass difference between the LSP and the gluino is small.

  18. Lasing in organic semiconductors - time-resolved studies of non-radiative decay processes

    CERN Document Server

    Zenz, C R

    2000-01-01

    Based on the demonstration of optical gain in an organic single crystal of a soluble oligo-phenylene-vinylene with gain values higher than 60 cm-1 and optically pumped lasing in a longitudinal adjustable microcavity based on laddertype polyparaphenylene, the realization of an organic laserdiode is discussed. The output characteristics of the microcavity can be modeled using classical rate equations, however the obtained threshold values are limited by the short excited state lifetime. A comparison with the lifetime measured on isolated molecules shows, that non-radiative decay processes in the solid state are determining the excited state lifetime. Using conventional and a novel field-assisted differential transmission spectroscopy with femtosecond time resolution, two main decay mechanism could be identified. (i) Triplet exciton in para-hexaphenyl is formed by non-geminate recombination of photo-generated polarons. (ii) Dissociation of the luminescent singlet excitons into polarons is important for two reaso...

  19. Radiative $h_{c/b}$ decays to $\\eta$ or $\\eta^\\prime$

    CERN Document Server

    Zhu, Ruilin

    2016-01-01

    Motivated by recent measurements of the radiative decay rates of the P-wave spin singlet charmonium $h_c$ to the light meson $\\eta$ or $\\eta^\\prime$ by the BESIII Collaboration, we investigate the decay rates of these channels at order $\\alpha \\alpha_s^4$. The photon is radiated mainly from charm quark pairs in the lowest order Feynman diagrams, since the diagrams where a photon radiated from light quarks are suppressed by $\\alpha_s$ or the relative charm quark velocity $v$, due to Charge parity conservation. The form factors of two gluons to $\\eta$ or $\\eta^\\prime$ are employed, which are the major mechanism for $\\eta$ and $\\eta^\\prime$ productions. $\\eta(\\eta^\\prime)$ is treated as a light cone object when we consider that the parent charmonium mass is much heavier than that of the final light meson. We obtain the branching ratio ${\\cal B}(h_c\\to \\gamma\\eta^\\prime) = (1.94^{+0.70}_{-0.51})\\times 10^{-3}$ in the nonrelativistic QCD approach, which is in agreement with the BESIII measurement. The prediction o...

  20. Radiative decays of the psi prime to all-photon final states

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R.A.

    1985-06-01

    Results of studies of selected radiative decays of the psi' to charmonium and non-charmonium states which decay into photons are presented. These studies were performed using a sample of 1.8 x 10/sup 6/ produced psi''s collected by the Crystal Ball detector at the SPEAR electron-positron storage ring. The branching ratios of the chi/sub 0/, chi/sub 2/, and eta'/sub c/ to two photons have been measured to be (4.5 +- 2.2 +- 2.0) x 10/sup -4/, (9.5 +- 2.9 +- 4.5) x 10/sup -4/ (first errors statistical, second systematic), and <1 x 10/sup -2/ (90% C.L.). The signal from the decay chain psi' ..-->.. ..gamma..chi/sub 0/, chi/sub 0/ ..-->.. ..pi../sup 0/..pi../sup 0/ has been observed with essentially no background. Using the observed line shape of the radiative photon in this reaction, the full width of the psi/sub 0/ has been found to be 8.8 +- 1.3 +- 1.5 MeV/c/sup 2/. In addition, the branching ratios of the chi/sub 0/ and chi/sub 2/ to ..pi../sup 0/..pi../sup 0/ have been measured to be (3.5 +- 0.3 +- 1.2) x 10/sup -3/ and (1.2 +- 0.2 +- 0.4) x 10/sup -3/; the branching ratios of the chi/sub 0/ and chi/sub 2/ to eta eta have been measured to be (2.8 +- 0.9 +- 1.3) x 10/sup -3/ and (8.4 +- 4.2 +- 4.0) x 10/sup -4/. The decays of the psi' to four non-charmonium states have been investigated. The branching ratios and upper limits of these decays have been normalized to the branching ratios of the corresponding decays from the J/psi which have been measured using a sample of 2.2 x 10/sup 6/ produced J/psi's collected by the Crystal Ball detector. The ratios of the psi' branching ratios to the J/psi branching ratios for the final states ..gamma..eta, ..gamma..eta', ..gamma..theta, and ..gamma..f have been measured to be <1.8%, <2.6%, <10 to 15%, and 9 +- 3%. These results are compared with the theoretical expectations of lowest-order quantum chromodynamics potential models. Substantial disagreement is found between theory and

  1. CPT Tests: Kaon vs neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Hitoshi

    2003-07-09

    CPT violation has an impressive limit in the neutral kaon system |m(K{sup 0})-m({bar K}{sup 0})| < 10{sup -18} m{sub K} = 0.50 x 10{sup -18} GeV. However, if viewed as a constraint on the mass-squared, the bound appears weak, |m{sup 2}(K{sup 0})-m{sup 2}({bar K}{sup 0})| < 0.25 eV{sup 2}. the authors point out that neutrino oscillation offers better limits on CPT violation in this case. The comparison of solar and rector neutrino results puts the best limit on CPT violation by far, |{Delta}m{sub {nu}}{sup 2}-{Delta}m{sub {rho}}{sup 2}| < 1.3 x 10{sup -3} eV{sup 2} (90% CL).

  2. Nucleon Resonances in Kaon Photoproduction

    CERN Document Server

    Bennhold, C; Waluyo, A; Haberzettl, H; Penner, G; Feuster, T; Mosel, U

    1999-01-01

    Nucleon resonances are investigated through the electromagnetic production of K-mesons. We study the kaon photoproduction process at tree-level and compare to a recently developed unitary K-matrix approach. Employing hadronic form factors along with the proper gauge prescription yields suppression of the Born terms and leads a resonance dominated process for both K-Lambda and K-Sigma photoproduction. Using new SAPHIR data we find the K+-Lambda photoproduction to be dominated by the S11(1650) at threshold, with additional contributions from the P11(1710) and P13(1720) states. The K-Sigma channel couples to a cluster of Delta resonances around W = 1900 MeV. We briefly discuss some tantalizing evidence for a missing D13 resonance around 1900 MeV with a strong branching ratio into KLambda channel.

  3. Radiation-induced growth and isothermal decay of infrared-stimulated luminescence from feldspar

    DEFF Research Database (Denmark)

    Guralnik, Benny; Li, Bo; Jain, Mayank

    2015-01-01

    Optically stimulated luminescence (OSL) ages can determine a wide range of geological events or processes, such as the timing of sediment deposition, the exposure duration of a rock surface, or the cooling rate of bedrock. The accuracy of OSL dating critically depends on our capability to describe...... the growth and decay of laboratory-regenerated luminescence signals. Here we review a selection of common models describing the response of infrared stimulated luminescence (IRSL) of feldspar to constant radiation and temperature as administered in the laboratory. We use this opportunity to introduce...

  4. Factorization of Radiative Leptonic Decays of $B^-$ and $D^-$ Mesons Including the Soft Photon Region

    CERN Document Server

    Yang, Ji-Chong

    2016-01-01

    In this work, we study the radiative leptonic decays of $B^-$ and $D^-$ mesons using factorization approach. Factorization is proved to be valid explicitly at 1-loop level at any order of $O(\\Lambda _{\\rm QCD}\\left/m_Q\\right.)$. We consider the contribution in the soft photon region that $E_{\\gamma} \\sim \\left. \\Lambda^2 _{\\rm QCD} /\\right. m_Q$. The numerical results shows that, the soft photon region is very important for both the $B$ and $D$ mesons. The branching ratios of $B\\to \\gamma e\

  5. Kaons in nuclear matter; Kaonen in Kernmaterie

    Energy Technology Data Exchange (ETDEWEB)

    Kolomeitsev, E.E.

    1997-02-01

    The subject of the doctoral thesis is examination of the properties of kaons in nuclear matter. A specific method is explained that has been developed for the scientific objectives of the thesis and permits description of the kaon-nucleon interactions and kaon-nucleon scattering in a vacuum. The main challenge involved was to find approaches that would enable application of the derived relations out of the kaon mass shell, connected with the second objective, namely to possibly find methods which are independent of models. The way chosen to achieve this goal relied on application of reduction formulas as well as current algebra relations and the PCAC hypothesis. (orig./CB) [Deutsch] Die Arbeit befasst sich mit der Untersuchung der Eigenschaften von Kao nen in Kernmaterie. Zu diesem Zweck wurde ein Verfahren entwickelt, di e Kaon- Nukleon- Wechselwirkung und Kaon- Nukleon- Streuung im Vakuumzu beschreiben. Die Hauptherausforderung bestand darin, dass die abgel eiteten Relationen ausserhalb der Kaonen- Massenschale anwendbar werde n. Eine Nebenforderung war, dass die vorgeschlagenen Verfahren moeglic hst modell- unabhaengig sind. Um dieses Ziel zu erreichen, wurden Redu ktionsformeln, Stromalgebra- Relationen und die PCAC- Hypothese angewe ndet.

  6. Measurement of the branching fraction and $CP$ asymmetry in radiative $D^0 \\to V \\gamma$ decays

    CERN Document Server

    Abdesselam, A; Adamczyk, K; Aihara, H; Said, S Al; Arinstein, K; Arita, Y; Asner, D M; Aso, T; Atmacan, H; Aulchenko, V; Aushev, T; Ayad, R; Aziz, T; Babu, V; Badhrees, I; Bahinipati, S; Bakich, A M; Bala, A; Ban, Y; Bansal, V; Barberio, E; Barrett, M; Bartel, W; Bay, A; Bedny, I; Behera, P; Belhorn, M; Belous, K; Besson, D; Bhardwaj, V; Bhuyan, B; Bischofberger, M; Biswal, J; Bloomfield, T; Blyth, S; Bobrov, A; Bondar, A; Bonvicini, G; Bookwalter, C; Boulahouache, C; Bozek, A; Bračko, M; Breibeck, F; Brodzicka, J; Browder, T E; Červenkov, D; Chang, M -C; Chang, P; Chao, Y; Chekelian, V; Chen, A; Chen, K -F; Chen, P; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, S -K; Choi, Y; Cinabro, D; Crnkovic, J; Dalseno, J; Danilov, M; Dash, N; Di Carlo, S; Dingfelder, J; Doležal, Z; Drásal, Z; Drutskoy, A; Dubey, S; Dutta, D; Dutta, K; Eidelman, S; Epifanov, D; Esen, S; Farhat, H; Fast, J E; Feindt, M; Ferber, T; Frey, A; Frost, O; Fujikawa, M; Fulsom, B G; Gaur, V; Gabyshev, N; Ganguly, S; Garmash, A; Getzkow, D; Gillard, R; Giordano, F; Glattauer, R; Goh, Y M; Goldenzweig, P; Golob, B; Greenwald, D; Perdekamp, M Grosse; Grygier, J; Grzymkowska, O; Guo, H; Haba, J; Hamer, P; Han, Y L; Hara, K; Hara, T; Hasegawa, Y; Hasenbusch, J; Hayasaka, K; Hayashii, H; He, X H; Heck, M; Hedges, M T; Heffernan, D; Heider, M; Heller, A; Higuchi, T; Himori, S; Hirose, S; Horiguchi, T; Hoshi, Y; Hoshina, K; Hou, W -S; Hsiung, Y B; Hsu, C -L; Huschle, M; Hyun, H J; Igarashi, Y; Iijima, T; Imamura, M; Inami, K; Inguglia, G; Ishikawa, A; Itagaki, K; Itoh, R; Iwabuchi, M; Iwasaki, M; Iwasaki, Y; Iwata, S; Jacobs, W W; Jaegle, I; Jeon, H B; Joffe, D; Jones, M; Joo, K K; Julius, T; Kakuno, H; Kang, J H; Kang, K H; Kapusta, P; Kataoka, S U; Kato, E; Kato, Y; Katrenko, P; Kawai, H; Kawasaki, T; Keck, T; Kichimi, H; Kiesling, C; Kim, B H; Kim, D Y; Kim, H J; Kim, H -J; Kim, J B; Kim, J H; Kim, K T; Kim, M J; Kim, S H; Kim, S K; Kim, Y J; Kinoshita, K; Kleinwort, C; Klucar, J; Ko, B R; Kobayashi, N; Koblitz, S; Kodyš, P; Koga, Y; Korpar, S; Kotchetkov, D; Kouzes, R T; Križan, P; Krokovny, P; Kronenbitter, B; Kuhr, T; Kumar, R; Kumita, T; Kurihara, E; Kuroki, Y; Kuzmin, A; Kvasnička, P; Kwon, Y -J; Lai, Y -T; Lange, J S; Lee, D H; Lee, I S; Lee, S -H; Leitgab, M; Leitner, R; Levit, D; Lewis, P; Li, C H; Li, H; Li, J; Li, L; Li, X; Li, Y; Gioi, L Li; Libby, J; Limosani, A; Liu, C; Liu, Y; Liu, Z Q; Liventsev, D; Loos, A; Louvot, R; Lubej, M; Lukin, P; Luo, T; MacNaughton, J; Masuda, M; Matsuda, T; Matvienko, D; Matyja, A; McOnie, S; Mikami, Y; Miyabayashi, K; Miyachi, Y; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Mohanty, G B; Mohanty, S; Mohapatra, D; Moll, A; Moon, H K; Mori, T; Morii, T; Moser, H -G; Müller, T; Muramatsu, N; Mussa, R; Nagamine, T; Nagasaka, Y; Nakahama, Y; Nakamura, I; Nakamura, K R; Nakano, E; Nakano, H; Nakano, T; Nakao, M; Nakayama, H; Nakazawa, H; Nanut, T; Nath, K J; Natkaniec, Z; Nayak, M; Nedelkovska, E; Negishi, K; Neichi, K; Ng, C; Niebuhr, C; Niiyama, M; Nisar, N K; Nishida, S; Nishimura, K; Nitoh, O; Nozaki, T; Ogawa, A; Ogawa, S; Ohshima, T; Okuno, S; Olsen, S L; Ono, Y; Onuki, Y; Ostrowicz, W; Oswald, C; Ozaki, H; Pakhlov, P; Pakhlova, G; Pal, B; Palka, H; Panzenböck, E; Park, C -S; Park, C W; Park, H; Park, K S; Paul, S; Peak, L S; Pedlar, T K; Peng, T; Pesántez, L; Pestotnik, R; Peters, M; Petrič, M; Piilonen, L E; Poluektov, A; Prasanth, K; Prim, M; Prothmann, K; Pulvermacher, C; Purohit, M V; Rauch, J; Reisert, B; Ribežl, E; Ritter, M; Röhrken, M; Rorie, J; Rostomyan, A; Rozanska, M; Rummel, S; Ryu, S; Sahoo, H; Saito, T; Sakai, K; Sakai, Y; Sandilya, S; Santel, D; Santelj, L; Sanuki, T; Sasao, N; Sato, Y; Savinov, V; Schlüter, T; Schneider, O; Schnell, G; Schönmeier, P; Schram, M; Schwanda, C; Schwartz, A J; Schwenker, B; Seidl, R; Seino, Y; Sekiya, A; Semmler, D; Senyo, K; Seon, O; Seong, I S; Sevior, M E; Shang, L; Shapkin, M; Shebalin, V; Shen, C P; Shibata, T -A; Shibuya, H; Shinomiya, S; Shiu, J -G; Shwartz, B; Sibidanov, A; Simon, F; Singh, J B; Sinha, R; Smerkol, P; Sohn, Y -S; Sokolov, A; Soloviev, Y; Solovieva, E; Stanič, S; Starič, M; Steder, M; Strube, J F; Stypula, J; Sugihara, S; Sugiyama, A; Sumihama, M; Sumisawa, K; Sumiyoshi, T; Suzuki, K; Suzuki, S; Suzuki, S Y; Suzuki, Z; Takeichi, H; Takizawa, M; Tamponi, U; Tanaka, M; Tanaka, S; Tanida, K; Taniguchi, N; Taylor, G N; Teramoto, Y; Tikhomirov, I; Trabelsi, K; Trusov, V; Tse, Y F; Tsuboyama, T; Uchida, M; Uchida, T; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Uozumi, S; Urquijo, P; Ushiroda, Y; Usov, Y; Vahsen, S E; Van Hulse, C; Vanhoefer, P; Varner, G; Varvell, K E; Vervink, K; Vinokurova, A; Vorobyev, V; Vossen, A; Wagner, M N; Wang, C H; Wang, J; Wang, M -Z; Wang, P; Wang, X L; Watanabe, M; Watanabe, Y; Wedd, R; Wehle, S; White, E; Wiechczynski, J; Williams, K M; Won, E; Yabsley, B D; Yamada, S; Yamamoto, H; Yamaoka, J; Yamashita, Y; Yamauchi, M; Yashchenko, S; Ye, H; Yelton, J; Yook, Y; Yuan, C Z; Yusa, Y; Zhang, C C; Zhang, L M; Zhang, Z P; Zhao, L; Zhilich, V; Zhukova, V; Zhulanov, V; Ziegler, M; Zivko, T; Zupanc, A; Zwahlen, N; Zyukova, O

    2016-01-01

    We report a measurement of the branching fractions of the radiative decays $D^0 \\to V \\gamma$, where $V=\\phi,~\\overline{K}{}^{*0}$ or $\\rho^0$. This is the first observation of the decay $D^0 \\to \\rho^0 \\gamma$. We measure preliminary branching fractions $\\mathcal{B}(D^0 \\to \\phi \\gamma)=(2.76 \\pm 0.20 \\pm 0.08) \\times 10^{-5}$, $\\mathcal{B}(D^0 \\to \\overline{K}{}^{*0} \\gamma)=(4.66 \\pm 0.21 \\pm 0.18) \\times 10^{-4} $ and $\\mathcal{B}(D^0 \\to \\rho^0 \\gamma)=(1.77 \\pm 0.30 \\pm 0.08) \\times 10^{-5}$, where the first uncertainty is statistical and the second systematic. We also present the first measurement of $CP$ asymmetry in these decays. The preliminary values are $\\mathcal{A}_{CP}(D^0 \\to \\phi \\gamma)=-(0.094 \\pm 0.066 \\pm 0.001)$, $\\mathcal{A}_{CP}(D^0 \\to \\overline{K}{}^{*0} \\gamma)=-(0.003 \\pm 0.020 \\pm 0.000)$ and $\\mathcal{A}_{CP}(D^0 \\to \\rho^0 \\gamma)=0.056 \\pm 0.151 \\pm 0.006$. The analysis was conducted using 943 fb$^{-1}$ of data collected by the Belle detector at the KEKB $e^+e^-$ collider.

  7. Fully radiative relaxation of silicon nanocrystals in colloidal ensemble revealed by advanced treatment of decay kinetics

    Science.gov (United States)

    Greben, Michael; Khoroshyy, Petro; Liu, Xiangkai; Pi, Xiaodong; Valenta, Jan

    2017-07-01

    A comprehensive study of the spectrally resolved photoluminescence (PL) decay kinetics of dodecyl-passivated colloidal silicon nanocrystals (Si NCs) is presented. The correct treatment of average decay lifetime is demonstrated. We report on importance to distinguish the external quantum efficiency (QE) from the internal QE. The external QE of the ensemble of Si NCs is measured to be ˜60%, while the internal QE of Si NCs emitting around ˜1.5 eV is evaluated to be near unity. This difference between internal and external QE is attributed to a fraction of "dark" (absorbing but non-emitting) Si NCs in the ensemble. This conclusion is based on the analysis of deconvoluted size-selected decay curves retrieved by the presented mathematical procedure. The homogeneous line-broadening is estimated to be around 180 meV by experimentally challenging single-NC PL measurements. In addition, radiative lifetimes are calculated by the envelope function approximation and confirm the observed exponential increase of lifetime with decreasing emission photon energy.

  8. Naturally Large Radiative Lepton Flavor Violating Higgs Decay Mediated by Lepton-flavored Dark Matter

    CERN Document Server

    Baek, Seungwon

    2015-01-01

    In the standard model (SM), lepton flavor violating (LFV) Higgs decay is absent at renormalizable level and thus it is a good probe to new physics. In this article we study a type of new physics that could lead to large LFV Higgs decay, i.e., a lepton-flavored dark matter (DM) model which is specified by the particle property of DM (a Majorana fermion) and DM-SM mediators (scalar leptons). Different from other similar setups, here we introduce both the left-handed and the right-handed scalar leptons. They allow large LFV Higgs decay and thus may explain the tentative Br$(h\\ra\\tau\\mu)\\sim1\\%$ experimental results from LHC. In particular, we find that the stringent bound from $\\tau\\ra\\mu\\gamma$ can be naturally evaded. One reason, among others, is a large chirality violation in the mediator sector. Aspects of relic density and especially radiative direct detection of the leptonic DM are also investigated, stressing the difference from previous lepton-flavored DM models.

  9. Steep Decay of GRB X-Ray Flares: The Results of Anisotropic Synchrotron Radiation

    Science.gov (United States)

    Geng, Jin-Jun; Huang, Yong-Feng; Dai, Zi-Gao

    2017-05-01

    When an emitting spherical shell with a constant Lorentz factor turns off emission abruptly at some radii, its high-latitude emission would obey the relation of \\hat{α } (the temporal index) = 2+\\hat{β } (the spectral index). However, this relation is violated by the X-ray fares in some gamma-ray bursts (GRBs), whose \\hat{α } is much more steeper. We show that the synchrotron radiation should be anisotropic when the angular distribution of accelerated electrons has a preferable orientation, and this anisotropy would naturally lead to a steeper decay for the high-latitude emission if the intrinsic emission is limb-brightened. We use this simple toy model to reproduce the temporal and spectral evolution of X-ray flares. We show that our model can well interpret the steep decay of the X-ray flares in the three GRBs selected as an example. Recent simulations on particle acceleration may support the specific anisotropic distribution of the electrons adopted in our work. Reversely, confirmation of the anisotropy in the radiation would provide meaningful clues to the details of electron acceleration in the emitting region.

  10. Radionuclide Ionization in Protoplanetary Disks: Calculations of Decay Product Radiative Transfer

    CERN Document Server

    Cleeves, L Ilsedore; Bergin, Edwin A; Visser, Ruud

    2013-01-01

    We present simple analytic solutions for the ionization rate $\\zeta_{\\rm{SLR}}$ arising from the decay of short-lived radionuclides (SLRs) within protoplanetary disks. We solve the radiative transfer problem for the decay products within the disk, and thereby allow for the loss of radiation at low disk surface densities; energy loss becomes important outside $R\\gtrsim30$ for typical disk masses $M_g=0.04$ M$_\\odot$. Previous studies of chemistry/physics in these disks have neglected the impact of ionization by SLRs, and often consider only cosmic rays (CRs), because of the high CR-rate present in the ISM. However, recent work suggests that the flux of CRs present in the circumstellar environment could be substantially reduced by relatively modest stellar winds, resulting in severely modulated CR ionization rates, $\\zeta_{\\rm{CR}}$, equal to or substantially below that of SLRs ($\\zeta_{\\rm{SLR}}\\lesssim10^{-18}$ s$^{-1}$). We compute the net ionizing particle fluxes and corresponding ionization rates as a func...

  11. Fourier Transform Infrared Radiation Spectroscopy Applied for Wood Rot Decay and Mould Fungi Growth Detection

    Directory of Open Access Journals (Sweden)

    Bjørn Petter Jelle

    2012-01-01

    Full Text Available Material characterization may be carried out by the attenuated total reflectance (ATR Fourier transform infrared (FTIR radiation spectroscopical technique, which represents a powerful experimental tool. The ATR technique may be applied on both solid state materials, liquids, and gases with none or only minor sample preparations, also including materials which are nontransparent to IR radiation. This facilitation is made possible by pressing the sample directly onto various crystals, for example, diamond, with high refractive indices, in a special reflectance setup. Thus ATR saves time and enables the study of materials in a pristine condition, that is, the comprehensive sample preparation by pressing thin KBr pellets in traditional FTIR transmittance spectroscopy is hence avoided. Materials and their ageing processes, both ageing by natural and accelerated climate exposure, decomposition and formation of chemical bonds and products, may be studied in an ATR-FTIR analysis. In this work, the ATR-FTIR technique is utilized to detect wood rot decay and mould fungi growth on various building material substrates. An experimental challenge and aim is to be able to detect the wood rot decay and mould fungi growth at early stages when it is barely visible to the naked eye. Another goal is to be able to distinguish between various species of fungi and wood rot.

  12. Measurement of Inclusive Radiative B -Meson Decay B -> X_s gamma

    Energy Technology Data Exchange (ETDEWEB)

    Ozcan, V.E.; /SLAC /Stanford U., Appl. Phys. Dept.

    2006-01-06

    Radiative decays of the B meson, B {yields} X{sub s}{gamma}, proceed via virtual flavor changing neutral current processes that are sensitive to contributions from high mass scales, either within the Standard Model of electroweak interactions or beyond. In the Standard Model, these transitions are sensitive to the weak interactions of the top quark, and relatively robust predictions of the inclusive decay rate exist. Significant deviation from these predictions could be interpreted as indications for processes not included in the minimal Standard Model, like interactions of charged Higgs or SUSY particles. The analysis of the inclusive photon spectrum from B {yields} X{sub s}{gamma} decays is rather challenging due to high backgrounds from photons emitted in the decay of mesons in B decays as well as e{sup +}e{sup -} annihilation to low mass quark and lepton pairs. Based on 88.5 million B{bar B} events collected by the BABAR detector, the photon spectrum above 1.9 GeV is presented. By comparison of the first and second moments of the photon spectrum with QCD predictions (calculated in the kinetic scheme), QCD parameters describing the bound state of the b quark in the B meson are extracted: m{sub b} = (4.45 {+-} 0.16) GeV/c{sup 2}; {mu}{sub {pi}}{sup 2} = (0.65 {+-} 0.29) GeV{sup 2}. These parameters are useful input to non-perturbative QCD corrections to the semileptonic B decay rate and the determination of the CKM parameter |V{sub ub}|. Based on these parameters and heavy quark expansion, the full branching fraction is obtained as: {Beta}(B {yields} X{sub s}{gamma}){sup E{sub {gamma}}>1.6 GeV} = (4.05 {+-} 0.32(stat) {+-} 0.38(syst) {+-} 0.29(model)) x 10{sup -4}. This result is in good agreement with previous measurements, the statistical and systematic errors are comparable. It is also in good agreement with the theoretical Standard Model predictions, and thus within the present errors there is no indication of any interactions not accounted for in the

  13. The radiative decay of a neutrino with a magnetic moment in a strong magnetic field with taking account of the positronium influence on the photon dispersion

    Science.gov (United States)

    Mosichkin, A. F.

    2016-02-01

    We study the process of the radiative decay of the neutrino with a magnetic moment in a strong magnetic field, with taking account of the influence of the positronium on the photon dispersion. The positronium contribution into the photon polarization operator leads to an essential modification of the photon dispersion law, and of the neutrino radiative decay amplitude. It has been shown that the probability of the neutrino radiative decay essentially increases under an influence of the positronium on the photon dispersion.

  14. Radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying hyperons and emitted charged leptons

    CERN Document Server

    Martínez, A; Flores-Mendieta, R; García, A

    2001-01-01

    We obtain a model-independent expression for the Dalitz plot of semileptonic decays of polarized hyperons including radiative corrections to order alpha and neglecting terms of order (alpha q)/(pi M_1), where q is the four-momentum transfer and M_1 is the mass of the decaying hyperon. We specialize our results to exhibit the correlation between the charged-lepton momentum and the spin of the decaying hyperon. We present results for the three-body region of the Dalitz plot and for the complete Dalitz plot (which includes the four-body region). From these results we also obtain the corresponding radiative corrections to the integrated lepton spin-asymmetry coefficient. Our formulas are valid for charged as well as for neutral decaying hyperons and are appropriate for model-independent experimental analysis whether the real photon is discriminated or not.

  15. Radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying hyperons and emitted charged leptons (17 pages)

    CERN Document Server

    Flores-Mendieta, R; Martínez, A; Torres, J J; Flores-Mendieta, Ruben

    2001-01-01

    We obtain a model-independent expression for the complete Dalitz plot of semileptonic decays of polarized hyperons, which includes both the three-body and the four-body regions. We calculate radiative corrections to order alpha, neglecting terms of order alpha q/(pi M_1), where q is the four-momentum transfer and M_1 is the mass of the decaying hyperon. Our results exhibit explicitly the correlation between the emitted hyperon three-momentum and the spin of the decaying hyperon. This allows us to obtain the corresponding radiative corrections to the integrated emitted hyperon spin-asymmetry coefficient. Our formulas are valid for charged as well as for neutral decaying hyperons and are appropriate for model-independent experimental analysis whether the real photon is discriminated or not.

  16. Search for a bound state of kaon and pion

    CERN Document Server

    Kishimoto, T; Hayakawa, T; Ajimura, S; Itabashi, T; Matsuoka, K; Minami, S; Mitoma, Y; Sakaguchi, A; Shimizu, Y; Terai, K; Sato, T; Noumi, H; Sekimoto, M; Takahashi, H; Fukuda, T; Imoto, W; Mizoi, Y

    2012-01-01

    We have searched for a bound state of kaon and pion denoted by $X$. The $X$ was conjectured to explain the so-called $\\Theta^+$ resonance as a bound state of kaon, pion and nucleon. This model explains almost all properties of the $\\Theta^+$, however, the model works only if the $K \\pi$ interaction is strongly attractive. It is so strong that it could make a bound state $X$. Here we report a result of the search for the $X$ by using the $K^+ + N \\rightarrow X^+ + N$ reaction at P$_K\\sim$ 1.2 GeV/c. The $X^+ \\rightarrow K^+ \\gamma \\gamma$ decay produces $K^+$ in momentum region where other processes cannot fill. We observed signature of the $X^+$ with statistical significance of 2 $\\sigma$. Production cross section of $X$ with respect to that of $\\pi^0$ is 1$\\pm$0.5% if we take it as an evidence and 1.5% if we set an upper limit.

  17. Induced polarization of {\\Lambda}(1116) in kaon electroproduction

    CERN Document Server

    Gabrielyan, M; Carman, D S; Park, K; Adhikari, K P; Adikaram, D; Amaryan, M J; Pereira, S Anefalos; Avakian, H; Ball, J; Baltzell, N A; Battaglieri, M; Baturin, V; Bedlinskiy, I; Biselli, A S; Bono, J; Boiarinov, S; Briscoe, W J; Brooks, W K; Burkert, V D; Cao, T; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Cortes, O; Crede, V; DAngelo, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; Fassi, L El; Eugenio, P; Fedotov, G; Fegan, S; Fleming, J A; Forest, T A; Garillon, B; Gevorgyan, N; Ghandilyan, Y; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Golovatch, E; Gothe, R W; Griffioen, K A; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hattawy, M; Hicks, K; Ho, D; Holtrop, M; Hughes, S M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Jenkins, D; Jiang, H; Jo, H S; Joo, K; Keller, D; Khandaker, M; Kim, W; Klein, F J; Koirala, S; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Lenisa, P; Levine, W I; Livingston, K; MacGregor, I J D; Mayer, M; McKinnon, B; Meyer, C A; Mestayer, M D; Mirazita, M; Mokeev, V; Moody, C I; Moutarde, H; Movsisyan, A; Munevar, E; Camacho, C Munoz; Nadel-Turonski, P; Niccolai, S; Niculescu, G; Osipenko, M; Pappalardo, L L; Paremuzyan, R; Pasyuk, E; Peng, P; Phelps, W; Phillips, J J; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Protopopescu, D; Rimal, D; Ripani, M; Rizzo, A; Sabatie, F; Salgado, C; Schott, D; Schumacher, R A; Simonyan, A; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Strakovsky, I I; Strauch, S; Sytnik, V; Tang, W; Ungaro, M; Vlassov, A V; Voskanyan, H; Voutier, E; Walford, N K; Watts, D P; Wei, X; Weinstein, L B; Zachariou, N; Zana, L; Zhang, J

    2014-01-01

    We have measured the induced polarization of the ${\\Lambda}(1116)$ in the reaction $ep\\rightarrow e'K^+{\\Lambda}$, detecting the scattered $e'$ and $K^+$ in the final state along with the proton from the decay $\\Lambda\\rightarrow p\\pi^-$.The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy $W$ ($1.6\\leq W \\leq 2.7$ GeV) and covered the full range of the kaon production angle at an average momentum transfer $Q^2=1.90$ GeV$^2$.In this experiment a 5.50 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the $W$ and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially $Q^2$ independent in our kinematic domain, suggesting that somewhere below the $Q^2$ covered here there must be a strong $Q^2$ dependence. Along wit...

  18. The radiative charmed baryon decay $\\Xi_{c2}^{0}$ --> $\\Xi_{c1}^{0}$ $\\gamma$

    CERN Document Server

    Lu, M; Walden, J W; Lu, Ming; Savage, Martin J; Walden, James

    1995-01-01

    V-spin symmetry (s \\leftrightarrow d symmetry) forbids the radiative decay \\Xi_{c2}^{0*} \\rightarrow \\Xi_{c1}^0 \\gamma in the SU(3) limit. The quark mass term breaks V-spin symmetry and the leading nonanalytic contribution to the radiative decay amplitude is computable in heavy baryon chiral perturbation theory. The radiative decay branching ratio is determined by the coupling constant g_2 and at leading order in chiral perturbation theory is given by Br(\\Xi_{c2}^{0*} \\rightarrow \\Xi_{c1}^0 \\gamma) = 1.0\\times 10^{-3} g_2^2. Measurement of this branching fraction will determine |g_2|.

  19. Fluorescence quenching and photobleaching in Au/Rh6G nanoassemblies: impact of competition between radiative and non-radiative decay

    Science.gov (United States)

    Dong, L.; Ye, F.; Hu, J.; Popov, S.; Friberg, A. T.; Muhammed, M.

    2011-04-01

    Fluorescence quenching from nanoassemblies formed by Rhodamine 6G and gold nanoparticles (Au NPs) of 2.6 nm radius has been investigated. The presence of Au NPs also induces long-term degradation of the photostability (photobleaching) of Rhodamine 6G used as gain medium in a Fabry-Perot laser cavity. We found that the degradation gets profound when the Au NPs concentration is significantly increased. Calculation of the radiative rate and direct time-resolved measurement of the fluorescence decay indicates that both the decrease of radiative decay rate and increase of non-radiative decay rate are responsible for the fluorescence quenching and photostability degradation. An energy transfer from the dye molecules to gold nanoparticles is dominating within the small distance between them and suppresses the quantum efficiency of Rhodamine 6G drastically. In long time scale, the photobleaching rate was slowing down, and laser output intensity reached a stabilized level which depends on the gold nanoparticles concentration.

  20. Strong and radiative decays of the $D_{s0}^*(2317)$ and $D_{s1}(2460)$

    CERN Document Server

    Cleven, Martin; Guo, Feng-Kun; Hanhart, Christoph; Meißner, Ulf-G

    2014-01-01

    Since their discovery in 2003, the open charm states $D_{s0}^*(2317)$ and $D_{s1}(2460)$ provide a challenge to the conventional quark model. In recent years, theoretical evidence has been accumulated for both states in favor of a predominantly $DK$ and $D^*K$ molecular nature, respectively. However, a direct experimental proof of this hypothesis still needs to be found. Since radiative decays are generally believed to be sensitive to the inner structure of the decaying particles, we study in this work the radiative and strong decays of both the $D_{s0}^*(2317)$ and $D_{s1}(2460)$, as well as of their counterparts in the bottom sector. While the strong decays are indeed strongly enhanced for molecular states, the radiative decays are of similar order of magnitude in different pictures. Thus, the experimental observable that allows one to conclusively quantify the molecular components of the $D_{s0}^*(2317)$ and $D_{s1}(2460)$ is the hadronic width, and not the radiative one, in contradistinction to common bel...

  1. Measurement of the radiative decay width {gamma}[{lambda}(1520)->{lambda}{gamma}] with the SPHINX spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, Yu.M. [Institute for High Energy Physics, Protvino (Russian Federation); Artamonov, A.V. [Institute for High Energy Physics, Protvino (Russian Federation); Batarin, V.A. [Institute for High Energy Physics, Protvino (Russian Federation); Vavilov, D.V. [Institute for High Energy Physics, Protvino (Russian Federation); Victorov, V.A. [Institute for High Energy Physics, Protvino (Russian Federation); Eroshin, O.V. [Institute for High Energy Physics, Protvino (Russian Federation); Golovkin, S.V. [Institute for High Energy Physics, Protvino (Russian Federation); Gorin, Yu.P. [Institute for High Energy Physics, Protvino (Russian Federation); Kolganov, V.Z. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Kozhevnikov, A.P. [Institute for High Energy Physics, Protvino (Russian Federation); Konstantinov, A.S. [Institute for High Energy Physics, Protvino (Russian Federation); Kubarovsky, V.P. [Institute for High Energy Physics, Protvino (Russian Federation); Kurshetsov, V.F. [Institute for High Energy Physics, Protvino (Russian Federation); Landsberg, L.G. [Institute for High Energy Physics, Protvino (Russian Federation)]. E-mail: lgl@mx.ihep.su; Leontiev, V.M. [Institute for High Energy Physics, Protvino (Russian Federation); Lomkatsi, G.S. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Molchanov, V.V. [Institute for High Energy Physics, Protvino (Russian Federation)]. E-mail: molchanov@mx.ihep.su; Mukhin, V.A. [Institute for High Energy Physics, Protvino (Russian Federation); Nilov, A.F. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Patalakha, D.I. [Institute for High Energy Physics, Protvino (Russian Federation); Petrenko, S.V. [Institute for High Energy Physics, Protvino (Russian Federation); Smolyankin, V.T. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation)

    2004-12-16

    The radiative decay {lambda}(1520)->{lambda}{gamma} was measured directly in the study of the exclusive diffractive-like reaction p+N->{lambda}(1520)K{sup +}+N, {lambda}(1520)->{lambda}{gamma} with the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR[{lambda}(1520)->{lambda}{gamma}]=(1.02+/-0.21(stat)+/-0.15(syst))x10{sup -2} and {gamma}[{lambda}(1520)->{lambda}{gamma}]=159+/-33(stat)+/-26(syst)-bar keV.

  2. X International Conference on Kaon Physics

    Science.gov (United States)

    2017-01-01

    The International Conference on Kaon Physics 2016 took place at the University of Birmingham (United Kingdom) on 14-17 September 2016. This conference continued the KAON series, offering an opportunity for theorists and experimentalists from the high-energy physics community to discuss all aspects of kaon physics. The 2016 edition saw a strong participation from theory and phenomenology and the first kaon results from the LHCb experiment at CERN, as well as updates from several experiments around the world including NA62 and KOTO. All papers published in this volume of KAON2016 have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing. The organizers and the participants wish to thank the University of Birmingham, the European Research Council, CERN, the UK Science and Technology Facility Council and the UK Institute for Particle Physics Phenomenology for their support in the organization of this successful edition. Figure for summary

  3. Exploring Hadron Structure Through Exclusive Kaon Electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Carmignotto, Marco A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2017-04-01

    The kaon electroproduction cross section was extracted from data from the E93-018 and the E01-004 (FPI-2) experiments taken at the Thomas Jefferson National Accelerator Facility in the p(e,e'K+)Λ channel. The cross section was fully separated into longitudinal, transverse, and two interference components at four-momentum transfers Q2 of 1.0 (GeV/c)2 (with center of mass energy W=1.81 GeV), 1.36 and 2.07 (GeV/c)2 (W=2.31 GeV). The kaon form factor (FK) was extracted from the longitudinal cross section in these kinematics using the Regge model by Vanderhaeghen, Guidal, and Laget. Results show FK to be systematically lower than the empirical monopole form, although still compatible with this form within the estimated uncertainties. The resulting kaon form factor values were combined with the world pion and kaon form factor data to extract the transverse change densities of the pion and kaon. These were compared to that of the proton, showing a possible experimental glimpse of the transition between the proton core and the meson cloud in terms of transverse densities.

  4. Revisiting RG Flow for Kaon Condensation

    CERN Document Server

    Paeng, Won-Gi

    2014-01-01

    Kaon condensation in compact-star matter can be considered as a quantum critical phenomenon with the kaon mass tuned to zero by the baryon density plus the electron chemical potential that increases at the increase of the density. We approach this problem with a renormalization group flow at one loop of the system of anti-kaons considered as pseudo-Goldstone bosons coupled to nucleonic matter described as a Fermi liquid near its fixed point. While the Weinberg-Tomozawa term in chiral Lagrangians is of leading order in describing kaon-nucleon interactions in chiral perturbation theory, hence widely employed in the literature, it is irrelevant in the RG sense, therefore plays, if any, a less important role in the condensation process. The consequence is that the $\\Lambda (1405)$ resonance which is driven by the Weinberg-Tomozawa term is irrelevant for triggering kaon condensation. On the contrary, the $KN$ sigma term $\\Sigma_{KN}$, subleading in chiral counting, can play a more crucial role in renormalization g...

  5. Transverse Flow of Kaons in Heavy-Ion Collisions

    Institute of Scientific and Technical Information of China (English)

    郑玉明; 储自力; FUCHS Christian; FAESSLER Amand; 肖武; 华大平; 阎玉鹏

    2002-01-01

    The transverse flow of positively charged kaons from heavy-ion collisions at intermediate energy is investigatedwithin the framework of the quantum molecular dynamics model. The calculated results show that the experi-mental data are only consistent with those including the kaon mean-field potential from the chiral Lagrangian.This indicates that the transverse flow pattern of kaons is a useful probe of the kaon potential in a nuclearmedium.

  6. Kaon experiments at CERN: recent results and prospects

    CERN Document Server

    Goudzovski, Evgueni

    2016-11-29

    The NA48/2 and NA62-$R_K$ experiments at the CERN SPS collected large samples of charged kaon decays in flight in 2003--07. The data analysis is still on-going (with over 20 publications produced so far); the recent results from these experiments are presented. A new upper limit on the rate of a lepton number violating decay $K^\\pm\\to\\pi^\\mp\\mu^\\pm\\mu^\\pm$ is reported: $\\mathcal{B} < 8.6\\times 10^{-11}$ at 90\\% CL. Searches for heavy sterile neutrino $N_4$ and neutral scalar resonances ($\\chi$) in $K^\\pm\\to\\pi\\mu\\mu$ decays are reported. Upper limits on the products $\\mathcal{B}(K^\\pm\\to\\mu^\\pm N_4)\\mathcal{B}(N_4\\to\\pi^\\mp\\mu^\\pm)$ and $\\mathcal{B}(K^\\pm\\to\\pi^\\pm \\chi)\\mathcal{B}(\\chi\\to\\mu^+\\mu^-)$ are set in the range $10^{-10}$ to $10^{-9}$ for resonance lifetimes up to 100~ps. A preliminary measurement of the electromagnetic transition form factor slope of the $\\pi^0$ from $1.05\\times 10^6$ fully reconstructed $\\pi^0\\to\\gamma e^+e^-$ decays is presented: the obtained result $a = (3.70 \\pm 0.53_\\text{...

  7. Kaon experiments at CERN: recent results and prospects

    Science.gov (United States)

    Goudzovski, Evgueni

    2016-11-01

    The NA48/2 and NA62-RK experiments at the CERN SPS collected large samples of charged kaon decays in flight in 2003-07. The data analysis is still on-going (with over 20 publications produced so far); the recent results from these experiments are presented. A new upper limit on the rate of a lepton number violating decay K± →π∓μ±μ± is reported: B< 8.6×10-11 at 90% CL. Searches for heavy sterile neutrino N4 and neutral scalar resonances (χ) in K± → πμμ decays are reported. Upper limits on the products B(K± → μ±N4)B(N4 → π∓μ±) and B(K± → π±χ)B(χ → μ+μ-) are set in the range 10-10 to 10-9 for resonance lifetimes up to 100 ps. A preliminary measurement of the electromagnetic transition form factor slope of the π0 from 1.05 × 106 fully reconstructed π0 → γe+e- decays is presented: the obtained result a = (3:70 ± 0:53stat ± 0:36syst) × 10-2 represents the first observation of a non-zero slope in the time-like region of momentum transfer.

  8. Hints for Enhanced $b \\to sg$ from Charm and Kaon Counting

    CERN Document Server

    Kagan, A L; Kagan, Alexander L.; Rathsman, Johan

    1997-01-01

    Previously, motivation for enhanced b -> sg from new flavor physics has centered on discrepancies between theory and experiment. Here two experimental hints are considered: (1) updated measurements of the charm multiplicity and BR(Bbar -> X_{ccbars}) at the Upsilon (4S) imply BR(B -> Xnocharm}) \\approx 12.4 \\pm 5.6 %, (2) the Bbar} -> K- X and Bbar -> K+/K- X branching fractions are in excess of conventional Bbar -> Xc -> KX yields by about 16.9 \\pm 5.6 % and 18 \\pm 5.3 %, respectively. JETSET 7.4 was used to estimate kaon yields from ssbar popping in Bbar -> Xcubard decays. JETSET 7.4 Monte Carlos for BR(Bbar -> Xsg) \\sim 15 % imply that the additional kaon production would lead to 1 \\sigma agreement with observed charged and neutral kaon yields. The Ks momentum spectrum would be consistent with recent CLEO bounds in the end point region. Search strategies for enhanced b -> sg are discussed in light of large theoretical uncertainty in the standard model fast kaon background from b -> s penguin operators.

  9. Observation of hc Radiative Decay hc→γ η' and Evidence for hc→γ η

    Science.gov (United States)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; de Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, S. G.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

    2016-06-01

    A search for radiative decays of the P -wave spin singlet charmonium resonance hc is performed based on 4.48 ×108 ψ' events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels hc→γ η' and γ η are observed with a statistical significance of 8.4 σ and 4.0 σ , respectively, for the first time. The branching fractions of hc→γ η' and hc→γ η are measured to be B (hc→γ η')=(1.52 ±0.27 ±0.29 )×10-3 and B (hc→γ η )=(4.7 ±1.5 ±1.4 )×10-4, respectively, where the first errors are statistical and the second are systematic uncertainties.

  10. Search for the Radiative Decays B -> rho gamma and B0 -> omega gamma

    CERN Document Server

    Aubert, Bernard; Boutigny, D; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; Kukartsev, G; Le Clerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmücker, H; Steinke, M; Barlow, N R; Bhimji, W; Boyd, J T; Chevalier, N; Cottingham, W N; MacKay, C; Wilson, F F; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M A; McMahon, S; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dorsten, M P; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Blanc, F; Bloom, P; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, Klaus R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Thiebaux, C; Vasileiadis, G; Verderi, M; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Bozzi, C; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Taylor, G P; Grenier, G J; Lee, S J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Bionta, R M; Brigljevic, V; Cheng, C H; Lange, D J; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, Erwin; Gamet, R; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Bellodi, G; Harrison, P F; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; Flächer, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Hart, P A; Jackson, F; Lafferty, G D; Lyon, A J; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Kovalskyi, D; Laé, K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Milek, M; Patel, P M; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, Gallieno; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; LoSecco, J M; Gabriel, T A; Brau, B; Pulliam, T; Brau, J E; Frey, R; Iwasaki, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; Leruste, P; Ocariz, J; Pivk, M; Roos, L; Stark, J; T'Jampens, S; Manfredi, P F; Re, V; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Leonardi, E; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Serra, M; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Convery, M R; Coupal, D P; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Field, R C; Glanzman, T; Gowdy, S J; Graugès-Pous, E; Hadig, T; Halyo, V; Hrynóva, T; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Menke, S; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Robertson, S H; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Tanaka, H A; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, Patricia R; Meyer, T I; Roat, C; Ahmed, S; Ernst, J A; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Hu, H; Johnson, J R; Liu, R; Di Lodovico, F; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; Von Wimmersperg-Töller, J H; Wu, J; Wu Sau Lan; Yu, Z; Neal, H

    2003-01-01

    A search for the exclusive radiative decays B --> rho(770) gamma and B0 --> omega(782) gamma is performed on a sample of about 84times 10^{6} Bbar B events collected by the BaBar detector at the PEP-II asymmetric-energy e+e- storage ring. No significant signal is seen in any of the channels. We set upper limits on the branching fractions of BR(B^0 -> rho^0 gamma) rho^+ gamma) omega gamma) rho gamma) = Gamma(B+ --> rho+ gamma) =2timesGamma(B0 --> rho0 gamma), we find the combined limit BR(B --> rho gamma) rho gamma)/BR(B --> K* gamma) < 0.047 at 90% C.L.

  11. Υ Radiative Decays to Light Quark Jets and Color Octet Mechanism

    Institute of Scientific and Technical Information of China (English)

    GAO Ying-Jia; ZHANG Yu-Jie; CHAO Kuang-Ta

    2006-01-01

    We study radiative decays of Υ to light quark jets in nonrelativistic QCD by taking both the color singlet and color octet b(b) operators into consideration. The cut for quark jet energy and cut for the angle between two quarkjets are introduced. The sensitivity to the soft and collinear singularities in the loop integrals are greatly reduced by these cuts. With the jet energy cut of about 1 GeV, and the jet angle cut of about 36°, the branching ratio for Υ→γq(q)is found to be 8.2 × 10-4 from color singlet contributions. The color octet contributions could be much larger than that of color singlet, depending on the estimate of the color octet matrix elements. This process may provide a new test for the color octet mechanism in nonrelativistic QCD.

  12. Study on the radiative decays of h{sub c} via intermediate meson loops model

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qi; Li, Gang; Zhang, Yawei [Qufu Normal University, College of Physics and Engineering, Qufu (China)

    2017-05-15

    Recently, the BESIII Collaboration reported two new decay processes: h{sub c}(1P) → γη and γη{sup '}. Inspired by this measurement, we propose to study the radiative decays of h{sub c} via intermediate charmed meson loops in an effective Lagrangian approach. With the acceptable cutoff parameter range, the calculated branching ratios of h{sub c}(1P) → γη and γη{sup '} are of the orders of 10{sup -4} to 10{sup -3} and 10{sup -3} to 10{sup -2}, respectively. The ratio R{sub h{sub c}} = B(h{sub c} → γη)/ B(h{sub c} → γη{sup '}) can reproduce the experimental measurements with the commonly acceptable α range. This ratio provide us with some information on the η-η{sup '} mixing, which may be helpful for us to test the SU(3)-flavor symmetries in QCD. (orig.)

  13. Revisiting radiative decays of $1^{+-}$ heavy quarkonia in the covariant light-front approach

    CERN Document Server

    Shi, Yan-Liang

    2016-01-01

    We revisit the calculation of the width for the radiative decay of a $1^{+-}$ heavy $Q \\bar Q$ meson via the channel $1^{+-} \\to 0^{-+} +\\gamma$ in the covariant light-front quark model. We carry out the reduction of the light-front amplitude in the non-relativistic limit, explicitly computing the leading and next-to-leading order relativistic corrections. This shows the consistency of the light-front approach with the non-relativistic formula for this electric dipole transition. Furthermore, the theoretical uncertainty in the predicted width is studied as a function of the inputs for the heavy quark mass and wavefunction structure parameter. We analyze the specific decays $h_{c}(1P) \\to \\eta_{c}(1S) + \\gamma$ and $h_{b}(1P) \\to \\eta_{b}(1S) + \\gamma$. We compare our results with experimental data and with other theoretical predictions from calculations based on non-relativistic models and their extensions to include relativistic effects, finding reasonable agreement.

  14. Revisiting radiative decays of 1{sup +-} heavy quarkonia in the covariant light-front approach

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yan-Liang [Stony Brook University, C. N. Yang Institute for Theoretical Physics, Stony Brook, NY (United States)

    2017-04-15

    We revisit the calculation of the width for the radiative decay of a 1{sup +-} heavy Q anti Q meson via the channel 1{sup +-} → 0{sup -+}+γ in the covariant light-front quark model. We carry out the reduction of the light-front amplitude in the non-relativistic limit, explicitly computing the leading and next-to-leading order relativistic corrections. This shows the consistency of the light-front approach with the non-relativistic formula for this electric dipole transition. Furthermore, the theoretical uncertainty in the predicted width is studied as a function of the inputs for the heavy-quark mass and wave function structure parameter. We analyze the specific decays h{sub c}(1P) → η{sub c}(1S) + γ and h{sub b}(1P) → η{sub b}(1S) + γ. We compare our results with experimental data and with other theoretical predictions from calculations based on non-relativistic models and their extensions to include relativistic effects, finding reasonable agreement. (orig.)

  15. Searches for the Anomalous Photon Polarisation in Radiative B Decays at LHCb

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00455305

    This thesis is exploring the measurements of the photon polarisation in radiative $B$ decays at LHCb, which are mediated through $b\\to s\\gamma$ transitions. To ensure optimal physics performance, procedures to align the LHCb detector and to monitor the alignment quality over time are presented. Using data corresponding to an integrated luminosity of $3~\\text{fb}^{-1}$, collected in the year of 2011 at the centre-of-energy $\\sqrt{s} = 7$~TeV and the year of 2012 at $\\sqrt{s} = 8$~TeV in proton-proton collisions, the photon polarisation parameter $A^\\Delta$, which is related to the ratio of right- over left-handed photon polarisation amplitudes in $b\\to s\\gamma$ transitions, is measured by performing an untagged time-dependent analysis of more than $4000$ $B_s^0\\to \\phi\\gamma$ decays. From an unbinned simultaneous fit to the $B_s^0\\to\\phi\\gamma$ and the control channel $B^0\\to{K^*}^0\\gamma$ data samples, a value of $A^\\Delta = -0.98^{~+0.46}_{~-0.52}\\text{(stat.)}^{~+0.23}_{~-0.20}\\text{(syst.)}$ is measured. T...

  16. Evidence for the eta(b)(1S) meson in radiative Upsilon(2S) decay.

    Science.gov (United States)

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B

    2009-10-16

    We have performed a search for the eta_{b}(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6x10(6) Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Egamma=609.3(-4.5)(+4.6)(stat)+/-1.9(syst) MeV, corresponding to an eta(b)(1S) mass of 9394.2(-4.9)(+4.8)(stat)+/-2.0(syst) MeV/c2. The branching fraction for the decay Upsilon(2S)-->gamma(eta)b(1S) is determined to be [3.9+/-1.1(stat)-0.9+1.1(syst)]x10(-4). We find the ratio of branching fractions B[Upsilon(2S)-->gamma(eta)b(1S)]/B[Upsilon(3S)-->gamma(eta)b(1S)]=0.82+/-0.24(stat)(-0.19)(+0.20)(syst).

  17. Evidence for the ηb(1S) Meson in Radiative Υ(2S) Decay

    Science.gov (United States)

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Zhang, L.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Bonneaud, G. R.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Chai, X.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Firmino da Costa, J.; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Saremi, S.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Marchiori, G.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Li Gioi, L.; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Renga, F.; Voena, C.; Ebert, M.

    2009-10-01

    We have performed a search for the ηb(1S) meson in the radiative decay of the Υ(2S) resonance using a sample of 91.6×106 Υ(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Eγ=609.3-4.5+4.6(stat)±1.9(syst)MeV, corresponding to an ηb(1S) mass of 9394.2-4.9+4.8(stat)±2.0(syst)MeV/c2. The branching fraction for the decay Υ(2S)→γηb(1S) is determined to be [3.9±1.1(stat)-0.9+1.1(syst)]×10-4. We find the ratio of branching fractions B[Υ(2S)→γηb(1S)]/B[Υ(3S)→γηb(1S)]=0.82±0.24(stat)-0.19+0.20(syst).

  18. Precision measurement of the radiative $\\beta$ decay of the free neutron

    CERN Document Server

    Bales, M J; Bass, C D; Beise, E J; Breuer, H; Byrne, J; Chupp, T E; Coakley, K J; Cooper, R L; Dewey, M S; Gardner, S; Gentile, T R; He, D; Mumm, H P; Nico, J S; O'Neill, B; Thompson, A K; Wietfeldt, F E

    2016-01-01

    The Standard Model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the $\\beta$ decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14~keV to 782~keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335 $\\pm$ 0.00005 [stat] $\\pm$ 0.00015 [syst]. A second detector array of large area avalanche photodiodes directly detected photons from 0.4~keV to 14~keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582 $\\pm$ 0.00023 [stat] $\\pm$ 0.00062 [syst]. We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies.

  19. Dynamics of strong and radiative decays of Ds-mesons in the hadrogenesis conjecture

    CERN Document Server

    Soyeur, Madeleine

    2009-01-01

    The positive parity scalar D$_{s0}^*$(2317) and axial-vector D$_{s1}^*$(2460) charmed strange mesons are generated by coupled-channel dynamics through the s-wave scattering of Goldstone bosons off the pseudoscalar and vector D(D$_s$)-meson ground states. The specific masses of these states are obtained as a consequence of the attraction arising from the Weinberg-Tomozawa interaction in the chiral Lagrangian. Chiral corrections to order Q$_\\chi^2$ are calculated and found to be small. The D$_{s0}^*$(2317) and D$_{s1}^*$(2460) mesons decay either strongly into the isospin-violating $\\pi^0$D$_s$ and $\\pi^0$D$_s^*$ channels or electromagnetically. We show that the $\\pi^0$-$\\eta$ and (K$^0$D$^+$-K$^+$D$^0$) mixings act constructively to generate strong widths of the order of 140 keV and emphasize the sensitivity of this value to the $KD$ component of the states. The one-loop contribution to the radiative decay amplitudes of scalar and axial-vector states is calculated using the electromagnetic Lagrangian to chiral...

  20. Possible radiative decays of solar neutrinos. Expectations from the total solar eclipse - 11th August 1999

    CERN Document Server

    Tanasa, A

    2001-01-01

    The paper treats the possibility of radiative decays of the oscillation product of the electron neutrinos coming from the Sun; to eliminate the background of photons collected with the telescope, the totality phase of the Total Solar Eclipse from August, 1999 in Romania will be used. To minimize this background in the NOTTE experiment (Neutrino Oscillation with Telescope during the Total Eclipse) one telescope will be mounted aboard a MIG29 plain flying in the totality band at high altitude. A theoretical calculation of the distribution of the distance from the center of the telescope for the decay photons is presented. Similar experiments could be placed aboard satellites having the advantage that the Earth occults the Sun every day while the detection time would be much longer than a typical eclipse duration. A positive result of such an experiment would be relevant not only for neutrino physics but also for astroparticle physics, dark matter searches and cosmology. Even negative results would lead to impro...

  1. RADIONUCLIDE IONIZATION IN PROTOPLANETARY DISKS: CALCULATIONS OF DECAY PRODUCT RADIATIVE TRANSFER

    Energy Technology Data Exchange (ETDEWEB)

    Cleeves, L. Ilsedore; Adams, Fred C.; Bergin, Edwin A.; Visser, Ruud [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States)

    2013-11-01

    We present simple analytic solutions for the ionization rate ζ{sub SLR} arising from the decay of short-lived radionuclides (SLRs) within protoplanetary disks. We solve the radiative transfer problem for the decay products within the disk, and thereby allow for the loss of radiation at low disk surface densities; energy loss becomes important outside R ∼> 30 AU for typical disk masses M{sub g} = 0.04 M{sub ☉}. Previous studies of chemistry/physics in these disks have neglected the impact of ionization by SLRs, and often consider only cosmic rays (CRs), because of the high CR-rate present in the interstellar medium. However, recent work suggests that the flux of CRs present in the circumstellar environment could be substantially reduced by relatively modest stellar winds, resulting in severely modulated CR ionization rates, ζ{sub CR}, equal to or substantially below that of SLRs (ζ{sub SLR} ∼< 10{sup –18} s{sup –1}). We compute the net ionizing particle fluxes and corresponding ionization rates as a function of position within the disk for a variety of disk models. The resulting expressions are especially simple for the case of vertically Gaussian disks (frequently assumed in the literature). Finally, we provide a power-law fit to the ionization rate in the midplane as a function of gas disk surface density and time. Depending on location in the disk, the ionization rates by SLRs are typically in the range ζ{sub SLR} ∼ (1-10) × 10{sup –19} s{sup –1}.

  2. Radiative decays of the psi(3097) to two meson final states

    Energy Technology Data Exchange (ETDEWEB)

    Einsweiler, K.F.

    1984-05-01

    The MARK III detector operating at the SPEAR storage ring has acquired a sample of 2.7 x 10/sup 6/ produced psi(3097)'s. These events are used to investigate the radiative decays of the psi to two meson final states. Such decays are of topical interest because of the unusual QCD laboratory they provide - of particular interest is the possibility of observing glueball states. The process psi ..-->.. ..gamma pi../sup +/..pi../sup -/ is studied. The f(1270) tensor meson is observed and the helicity structure of its production is measured. The data indicate that helicity 2 is suppressed, in disagreement with lowest order QCD calculations. Evidence is presented for the first observation of the theta(1700) in the ..pi../sup +/..pi../sup -/ final state. The strong, but not complete, suppression of this state in the ..pi pi.. channel, combined with the absence of a J/sup P/ = 2/sup +/ signal in a recent MARK III analysis of psi ..-->.. ..gamma.. rho rho, suggest a very mysterious nature for the theta(1700). The process psi ..-->.. ..gamma..K/sup +/K/sup -/ is also studied. The f'(1515) tensor meson is observed with a branching ratio in agreement with the SU(3) symmetry prediction for the standard two gluon radiative decay diagram with no mixing corrections. The helicity structure of the f'(1515) is measured for the first time, and is found to be similar to that of the f(1270). The theta(1700) is observed with high statistics. Its spin and parity are measured, with the result that J/sup P/ = 2/sup +/ is preferred over J/sup P/ = 0/sup +/ at the 99.9% C.L. In addition, evidence is presented for a remarkable narrow state, designated the xi(2220). Its parameters are measured to be: m = 2.218 +- 0.003 +- 0.010 GeV, GAMMA less than or equal to 0.040 GeV at 95% C.L., and BR(psi ..-->.. ..gamma..xi(2220))BR(xi(2220) ..-->.. K/sup +/K/sup -/) = (5.7 +- 1.9 +- 1.4) x 10/sup -5/.

  3. Quark model for kaon nucleon scattering

    Indian Academy of Sciences (India)

    Ahmed Osman

    2011-12-01

    Kaon nucleon elastic scattering is studied using chiral (3) quark model including antiquarks. Parameters of the present model are essentially based on nucleon–nucleon and nucleon–hyperon interactions. The mass of the scalar meson is taken as 635 MeV. Using this model, the phase shifts of the and partial waves of the kaon nucleon elastic scattering are investigated for isospins 0 and 1. The results of the numerical calculations of different partial waves are in good agreement with experimental data.

  4. Search for CP symmetry violation in the three pion decay mode of the K0 meson

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, Nancy Lee [Univ. of Minnesota, Minneapolis, MN (United States)

    1990-01-01

    Experimental measurements of CP symmetry violating parameters can make important contributions to our understanding of the electroweak interaction. At present the only well known values of CP symmetry violating parameters are determined from K → 2π decays. The theoretical parameter of interest is ϵ' which measures CP symmetry violation in the decay matrix element of the neutral kaon. The final sample was over 122, 000 kaons decaying in this mode.

  5. Measurement of the branching ratio of the long lived neutral kaon decay into a muon pair and a photon, and development of a trigger system in the NA48 experiment at CERN; Mesure du rapport d`embranchement de la desintegration K{sub l}{yields}{mu}{sup +}{mu}{sup -}{gamma} et developpement d`un systeme de declenchement dans l`experience NA48 au CERN

    Energy Technology Data Exchange (ETDEWEB)

    Schanne, S

    1997-10-24

    The study of direct CP violation in the neutral K meson system is the primary goal of the high precision NA 48 experiment at CERN, based on a spectrometer and a liquid krypton calorimeter. This experiment is also sensitive to rare kaon decays, in particular the one of the K{sub L} into a muon pair and a photon, discussed on the first part of he dissertation. The second part presents a detailed description on the second level `charged` trigger system of the experiment, operating at a 100 kHz event input rate. Its aim is to select the decays of K{sub L} or K{sub S} into a pair of charged pions, based on a high speed digital signal processor farm performing the online reconstruction of the invariant mass of an event in less than 100 microseconds, using the spectrometer data for an efficient rejection of the physical backgrounds. The reconstruction algorithm, the realization of the farm and its performances are presented. The third part determines a measurement of the branching ratio of the K{sub L} decay into a pair of muons and a proton using the data taken in 1995. 59 signal events are found containing a background estimated to 14. The results is 3.4{+-}0.6 (stat) {+-} 0.4 (syst) x 10{sup -7} and allows the determination of the value of the ratio between the coupling constants of the weak non leptonic transitions through vector and pseudo-scalar intermediate states {alpha}{sub K} = 0.048680{sub .21}{sup +024}. A search for decays of K{sub l} into two muons and two electrons has been performed. No candidate has been found. An upper limit for the branching fraction of the process of 3.8 x 10{sup -8} at a 90 % confidence level is obtained. (author) 86 refs.

  6. First observation and branching fraction and decay parameter measurements of the weak radiative decay $\\Xi^0 \\to \\Lambda e^{+}e^{-}$

    CERN Document Server

    Batley, J Richard; Lazzeroni, C; Munday, D J; Patel, M; Slater, M W; Wotton, S A; Arcidiacono, R; Bocquet, G; Ceccucci, A; Cundy, Donald C; Doble, N; Falaleev, V; Gatignon, L; Gonidec, A; Grafstrm, P; Kubischta, Werner; Mikulec, I; Norton, A; Panzer-Steindel, B; Rubin, P; Wahl, H; Goudzovski, E; Khristov, P Z; Kekelidze, V D; Litov, L; Madigozhin, D T; Molokanova, N A; Potrebenikov, Yu K; Stoynev, S; Zinchenko, A I; Monnier, E; Swallow, E; Winston, R; Sacco, R; Walker, A; Baldini, W; Dalpiaz, P; Frabetti, P L; Gianoli, A; Martini, M; Petrucci, F; Savrié, M; Scarpa, M; Bizzeti, A; Calvetti, M; Collazuol, G; Iacopini, E; Lenti, M; Veltri, M; Ruggiero, G; Behler, M; Eppard, K; Eppard, M; Hirstius, A; Kleinknecht, K; Koch, U; Marouelli, P; Masetti, L; Moosbrugger, U; Morales-Morales, C; Peters, A; Wanke, R; Winhart, A; Dabrowski, A; Fonseca-Martin, T; Velasco, M; Anzivino, Giuseppina; Cenci, P; Imbergamo, E; Lamanna, G; Lubrano, P; Michetti, A; Nappi, A; Pepé, M; Valdata, M; Petrucci, M C; Piccini, M; Cerri, C; Costantini, F; Fantechi, R; Fiorini, L; Giudici, S; Mannelli, I; Pierazzini, G M; Sozzi, M; Cheshkov, C; Chèze, J B; De Beer, M; Debu, P; Gouge, G; Marel, Gérard; Mazzucato, E; Peyaud, B; Vallage, B; Holder, M; Maier, A; Ziolkowski, M; Biino, C; Cartiglia, N; Clemencic, M; Goy-Lopez, S; Marchetto, F; Menichetti, E; Pastrone, N; Wislicki, W; Dibon, Heinz; Jeitler, Manfred; Markytan, Manfred; Neuhofer, G; Widhalm, L

    2007-01-01

    The weak radiative decay $Xi^0 -> \\Lambda e^+ e^- $ has been detected for the first time. We find 412 candidates in the signal region, with an estimated background of $15pm 5$ events. We determine the branching fraction ${cal{B}}(\\Xi^0 -> \\Lambda e^+ e^- ) = [7.6pm 0.4({m stat})pm 0.4({m syst})pm 0.2({m norm})] imes 10^{-6}$, consistent with an internal bremsstrahlung process, and the decay asymmetry parameter $\\alpha_{\\Xi \\Lambda ee} = -0.8pm 0.2$, consistent with that of $\\Xi^0 -> \\Lambda \\gamma$. The charge conjugate reaction $\\overline{\\Xi^{0}} -> \\overline{\\Lambda} e^+ e^- $ has also been observed.

  7. Understanding and eliminating non-radiative decay in organic-inorganic perovskites (Conference Presentation)

    Science.gov (United States)

    Stranks, Samuel D.; de Quilettes, Dane

    2016-09-01

    Organic-inorganic perovskites such as CH3NH3PbI3 are highly promising materials for a variety of optoelectronic applications, with certified power conversion efficiencies in solar cells already exceeding 21% and promising applications in light-emitting diodes, lasers and photodetectors also emerging. A key enabling property of the perovskites is their high photoluminescence quantum efficiency, suggesting that these materials could in principle approach the thermodynamic device efficiency limits in which all recombination is radiative. However, non-radiative recombination sites are present which vary heterogeneously from grain to grain and limit device performance. Here, I will present results where we probe the local photophysics of neat CH3NH3PbI3 perovskite films using confocal photoluminescence (PL) measurements and correlate the observations with the local chemistry of the grains using energy-dispersive X-ray spectroscopy (EDX) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). We investigate the connection between grains that are bright or dark in emission and the local Pb:I ratios at the surface and through the grains. We also examine how the photophysics, local chemistry and non-radiative decay pathways change slowly over time under illumination. Our results reveal a "photo-induced cleaning" arising from a redistribution of iodide content in the films, giving strong evidence for photo-induced ion migration. These slow transient effects appear to be related to anomalous hysteresis phenomena observed in full solar cells. I will discuss how immobilizing ions, reducing trap densities and achieving homogenous stoichiometries could suppress hysteresis effects and lead to devices approaching the efficiency limits.

  8. Study of KS semileptonic decays and CPT test with the KLOE detector

    CERN Document Server

    Kamińska, Daria

    2015-01-01

    Study of semileptonic decays of neutral kaons allows to perform a test of discrete symmetries, as well as basic principles of the Standard Model. In this paper a general review on dependency between charge asymmetry constructed for semileptonic decays of short- and long-lived kaons and CPT symmetry is given. The current status of determination of charge asymmetry for short-lived kaon, obtained by reconstruction of about 10^5 KS -> pen decays collected at DAFNE with the KLOE detector is also reviewed.

  9. Neutrino emissivity under neutral kaon condensation

    CERN Document Server

    Kubis, S

    2006-01-01

    Neutrino emissivity from neutron star matter with neutral kaon condensate is considered. It is shown that a new cooling channel is opened, and what is more, all previously known channels acquire the greater emissivity reaching the level of the direct URCA cycle in normal matter.

  10. Nonlinear Effect on Effective Mass of Kaon

    Institute of Scientific and Technical Information of China (English)

    LiXiguo; GuoYanrui; GaoYuan; JinGenming

    2003-01-01

    The study of hardron properties in dense medium crekted in relativistic heavy ion collision is a subject of considerable current interest. Of particular importance is the modification of kaon properties in-medium. The knowledge is useful for our understanding of both chiral symmetry restoration in dense matter and the properties of the dense nuclear matter existing in neutron stars.

  11. Neutrino emissivity under neutral kaon condensation

    OpenAIRE

    Kubis, Sebastian

    2005-01-01

    Neutrino emissivity from neutron star matter with neutral kaon condensate is considered. It is shown that a new cooling channel is opened, and what is more, all previously known channels acquire the greater emissivity reaching the level of the direct URCA cycle in normal matter.

  12. Exclusive channels in semi-inclusive production of pions and kaons

    Energy Technology Data Exchange (ETDEWEB)

    Markus Diehl; Wolfgang Kugler; Andreas Schaefer; Christian Weiss

    2005-06-01

    We investigate the role of exclusive channels in semi-inclusive electroproduction of pions and kaons. Using the QCD factorization theorem for hard exclusive processes we evaluate the cross sections for exclusive pseudoscalar and vector meson production in terms of generalized parton distributions and meson distribution amplitudes. We investigate the uncertainties arising from the modeling of the nonperturbative input quantities. Combining these results with available experimental data, we compare the cross sections for exclusive channels to that obtained from quark fragmentation in semi-inclusive deep inelastic scattering. We find that rho0 production is the only exclusive channel with significant contributions to semi-inclusive pion production at large z and moderate Q2. The corresponding contribution to kaon production from the decay of exclusively produced phi and Kstar is rather small.

  13. Search for di-muon decays of a light scalar Higgs boson in radiative Y(1S) decays

    CERN Document Server

    Prasad, Vindhyawasini

    2013-01-01

    We search for di-muon decays of a low-mass Higgs boson ($A^0$) in the fully reconstructed decay chain of $\\Upsilon(2S,3S) \\to \\pipi\\Upsilon(1S)$, $\\Upsilon(1S) \\to \\g A^0$, $A^0 \\to \\mumu$. The $A^0$ is predicted by several extensions of the Standard Model (SM), including the Next-to-Minimal Supersymmetric Standard Model (NMSSM). NMSSM introduces a \\CP-odd light Higgs boson whose mass could be less than 10 \\gevcc. The data samples used in this analysis contain $92.8 \\times 10^6$ $\\Upsilon(2S)$ and $116.8 \\times 10^6$ $\\Upsilon(3S)$ events collected by the \\babar\\ detector. The $\\Upsilon(1S)$ sample is selected by tagging the pion pair in the $\\Upsilon(2S, 3S) \\to \\pi^+\\pi^-\\Upsilon(1S)$ transitions. We find no evidence for $A^0$ production and set 90% confidence level (C.L.) upper limits on the product branching fraction $\\mathcal{B}(\\Upsilon(1S) \\to \\g A^0) \\times \\mathcal{B}(A^0 \\to \\mumu)$ in the range of $(0.28 - 9.7)\\times 10^{-6}$ for $0.212 \\le m_{A^0} \\le 9.20$ \\gevcc. We also combine our results with...

  14. Bs mesons: semileptonic and nonleptonic decays

    Directory of Open Access Journals (Sweden)

    Albertus C.

    2014-01-01

    Full Text Available In this contribution we compute some nonleptonic and semileptonic decay widths of Bs mesons, working in the context of constituent quark models [1, 2]. For the case of semileptonic decays we consider reactions leading to kaons or different Jπ Ds mesons. The study of nonleptonic decays has been done in the factorisation approximation and includes the final states enclosed in Table 2.

  15. Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma

    CERN Document Server

    Aubert, B; Karyotakis, Yu; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Graugès-Pous, E; Lopezab, L; Palanoab, A; Pappagalloab, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N; Jacobsen, R G; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabé, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schröder, T; Walker, D; Asgeirsson, D J; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Teodorescu, L; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Wilson, M G; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Clifton, Z C; Ford, W T; Gaz, A; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Smith, J G; Ulmer, K A; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Mader, W F; Nogowski, R; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, C; Verderi, M; Clark, P J; Gradl, W; Playfer, S; Watson, J E; Andreottiab, M; Bettonia, D; Bozzia, C; Calabreseab, R; Cecchiab, A; Cibinettoab, G; Franchiniab, P; Luppiab, E; Negriniab, M; Petrellaab, A; Piemontesea, L; Santoroab, V; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzoa, A; Contriab, R; Lo Vetereab, M; Macria, M M; Mongeab, M R; Passaggioa, S; Patrignaniab, C; Robuttia, E; Santroniab, A; Tosiab, S; Chaisanguanthum, K S; Morii, M; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Klose, V; Lacker, H M; De Nardoab, G; Listaa, L; Monorchioab, D; Onoratoab, G; Sciaccaab, C; Bard, D J; Dauncey, P D; Nash, J A; Panduro-Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Bquilleux, J; D'Orazio, A; Davier, M; Firminoda Costa, J; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Flächer, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Alwyn, K E; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Hertzbach, S S; Li, X; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaroab, A; Lombardoa, V; Palomboab, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J E; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelliab, G; Gagliardiab, N; Margoniab, M; Morandina, M; Posoccoa, M; Rotondoa, M; Simonettoab, F; Stroiliab, R; Vociab, C; Del Amo-Sánchez, P; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; Hamon, O; Leruste, P; Ocariz, J; Pérez, A; Prendki, J; Gladney, L; Biasiniab, M; Covarelliab, R; Manoniab, E; Angeliniab, C; Batignaniab, G; Bettariniab, S; Carpinelliab, M; Cervelliab, A; Fortiab, F; Giorgiab, M A; Lusianiac, A; Marchioriab, G; Morgantiab, M; Neriab, N; Paoloniab, E; Rizzoab, G; Walsha, J J; Biesiada, J; Lopes-Pegna, D; Lü, C; Olsen, J; Smith, A J S; Telnov, A V; Anullia, F; Baracchiniab, E; Cavotoa, G; del Reab, D; Di Marcoab, E; Facciniab, R; Ferrarottoa, F; Ferroniab, F; Gasperoab, M; Jacksona, P D; Li Gioia, L; Mazzonia, M A; Morgantia, S; Pireddaa, G; Polciab, F; Rengaab, F; Voenaa, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Röthel, W; Wilson, F F; Emery, S; Escalier, M; Esteve, L; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Y`che, C; Zito, M; Chen, X R; Liu, H; Park, e W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Lüth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Müller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Vavra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchiab, F; Gambaab, D; Pelliccioniab, M; Bombenab, M; Bosisioab, L; Cartaroab, C; Della Riccaab, G; Lanceriab, L; Vitaleab, L; Azzolini, V; Lopez-March, N; Martínez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, S; Bhuyan, B; Choi, H H F; Hamano, K; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Pierini, M; Prepost, R; Vuosalo, C O; Wu, S L

    2008-01-01

    We present measurements of the CP-violation parameters S and C for the radiative decay B0 -> eta K0s gamma; for B -> eta K gamma we also measure the branching fractions and for B+ -> eta K+ gamma the time-integrated charge asymmetry Ach. The data, collected with the BaBar detector at the Stanford Linear Accelerator Center, represent $465 \\times 10^6$ BBbar pairs produced in $e^{+} e^{-}$ annihilation. The results are $S = -0.18^{+0.49}_{-0.46} \\pm 0.12$, $C = -0.32^{+0.40}_{-0.39} \\pm 0.07$, BF(B0 -> eta K0 gamma) = $(7.1^{+2.1}_{-2.0} \\pm 0.4) \\times 10^{-6}$, BF(B+ -> eta K+ gamma) = $(7.7+-1.0 \\pm 0.4) \\times 10^{-6}$, and Ach = $(-9.0^{+10.4}_{-9.8} \\pm 1.4) \\times 10^{-2}$. The first error quoted is statistical and the second systematic.

  16. Updated NNLO QCD predictions for the weak radiative B-meson decays

    CERN Document Server

    Misiak, M; Boughezal, R; Czakon, M; Ewerth, T; Ferroglia, A; Fiedler, P; Gambino, P; Greub, C; Haisch, U; Huber, T; Kaminski, M; Ossola, G; Poradzinski, M; Rehman, A; Schutzmeier, T; Steinhauser, M; Virto, J

    2015-01-01

    We perform an updated analysis of the inclusive weak radiative B-meson decays in the standard model, incorporating all our results for the O(alpha_s^2) and lower-order perturbative corrections that have been calculated after 2006. New estimates of non-perturbative effects are taken into account, too. For the CP- and isospin-averaged branching ratios, we find B_{s gamma} = (3.36 +_ 0.23) * 10^-4 and B_{d gamma} = 1.73^{+0.12}_{-0.22} * 10^-5, for E_gamma > 1.6 GeV. These results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain R_gamma = ( B_{s gamma} + B_{d gamma})/B_{c l nu} = (3.31 +_ 0.22) * 10^-3. A new bound from B_{s gamma} on the charged Higgs boson mass in the two-Higgs-doublet-model II reads M_{H^+} > 480 GeV at 95%C.L.

  17. Relativistic electron acceleration and decay time scales in the inner and outer radiation belts: SAMPEX

    Science.gov (United States)

    Baker, D. N.; Blake, J. B.; Callis, L. B.; Cummings, J. R.; Hovestadt, D.; Kanekal, S.; Klecker, B.; Mewaldt, R. A.; Zwickl, R. D.

    1994-01-01

    High-energy electrons have been measured systematically in a low-altitude (520 x 675 km), nearly polar (inclination = 82 deg) orbit by sensitive instruments onboard the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX). Count rate channels with electron energy thresholds ranging from 0.4 MeV to 3.5 MeV in three different instruments have been used to examine relativistic electron variations as a function of L-shell parameter and time. A long run of essentially continuous data (July 1992 - July 1993) shows substantial acceleration of energetic electrons throughout much of the magnetosphere on rapid time scales. This acceleration appears to be due to solar wind velocity enhancements and is surprisingly large in that the radiation belt 'slot' region often is filled temporarily and electron fluxes are strongly enhanced even at very low L-values (L aprroximately 2). A superposed epoch analysis shows that electron fluxes rise rapidly for 2.5 is approximately less than L is approximately less than 5. These increases occur on a time scale of order 1-2 days and are most abrupt for L-values near 3. The temporal decay rate of the fluxes is dependent on energy and L-value and may be described by J = Ke-t/to with t(sub o) approximately equals 5-10 days. Thus, these results suggest that the Earth's magnetosphere is a cosmic electron accelerator of substantial strength and efficiency.

  18. Power-law decay of collisionally excited amino acids and quenching by radiative cooling

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, J.U.; Hvelplund, P.; Liu, B.; Brondsted Nielsen, S.; Perdersen, U.V.; Tomita, S. [Aarhus Univ., Dept. for Fysik og Astronomi (Denmark); Cederquist, H.; Jensen, J.; Schmidt, H.T.; Zettergren, H. [Stockholm Univ. (Sweden). Dept. of Physics; Forster, J.S. [Montreal Univ., PQ (Canada). Dept. of Physics; Huber, B.A.; Manil, B.; Maunoury, L. [Centre Interdisciplinaire de Recherche Ions Lasers, 14 - Caen (France)

    2003-08-01

    We have investigated the time dependence of the fragmentation of protonated amino acids stored at 22 keV in the electrostatic ring ELISA. The ions were produced in an electro-spray source and after bunching in a quadrupole trap they were excited by collisions in a Ne gas. As in earlier studies of metal clusters and fullerenes produced in 'hot' ion sources we find that the dissociation of metastable molecules follows approximately a 1/t decay law until a time {tau} after which the yield falls off much more rapidly. We interpret this reduction as a result of radiative cooling with a characteristic cooling time, {tau}{sub c} {approx} G{tau}, where G is the magnitude of the exponent in an Arrhenius expression for the rate of the dominant fragmentation process. The values of {tau} obtained from fits to the data are in the range 9-17 ms corresponding to cooling times of a few hundred milliseconds, in good accord with the expected rate of cooling by emission from IR-active vibrations. The power-law behaviour for t < {tau} varies somewhat between the different amino acids, with powers between -0.9 and -1.1. We argue that this may be due to a competition between fragmentation channels with different Arrhenius parameters. (authors)

  19. Neutral kaon decay without symmetry violation a nonstandard theoretical speculation

    CERN Document Server

    Hannibal, L

    1995-01-01

    It is shown that if antiparticles are realized in quantum field theory by negative frequency states, which nevertheless have positive energy density, the resulting theory provides a qualitative explanation for the experiments on the neutral K mesons, without assumming any symmetry violation.

  20. Rare kaon decays: $K^{+} → ^{+} \\bar{}$ and future

    Indian Academy of Sciences (India)

    Bipul Bhuyan

    2004-03-01

    The experimental progress in the search for $K^{+} → ^{+} \\bar{}$ will be presented in this paper. Also the physics potential of the proposed BNL experiment to search for $K_{L}^{0} → ^{0} \\bar{}$ (KOPIO) will be discussed.

  1. Search for New Physics in Neutral Kaon Decays

    Energy Technology Data Exchange (ETDEWEB)

    Comfort, Joseph R. [Arizona State Univ., Tempe, AZ (United States)

    2016-04-30

    This report will summarize contributions made by the ASU group during the grant period. Focus will be given to three areas: (1) Monte Carlo simulations; (2) signal processing in the electronics; and (3) data analysis software. For reference, a drawing of the KOTO detector is shown in Fig. 1. The production target for the neutral beam particles was about 20 meters upstream of the detector.

  2. Kaon Condensates, Nuclear Symmetry Energy and Cooling of Neutron Stars

    CERN Document Server

    Kubis, S

    2003-01-01

    The cooling of neutron stars by URCA processes in the kaon-condensed neutron star matter for various forms of nuclear symmetry energy is investigated. The kaon-nucleon interactions are described by a chiral lagrangian. Nuclear matter energy is parametrized in terms of the isoscalar contribution and the nuclear symmetry energy in the isovector sector. High density behaviour of nuclear symmetry energy plays an essential role in determining the composition of the kaon-condensed neutron star matter which in turn affects the cooling properties. We find that the symmetry energy which decreases at higher densities makes the kaon-condensed neutron star matter fully protonized. This effect inhibits strongly direct URCA processes resulting in slower cooling of neutron stars as only kaon-induced URCA cycles are present. In contrast, for increasing symmetry energy direct URCA processes are allowed in the almost whole density range where the kaon condensation exists.

  3. Nonequilibrium Weak Processes in Kaon Condensation; 2, Kinetics of condensation

    CERN Document Server

    Muto, T; Iwamoto, N; Muto, Takumi; Tatsumi, Toshitaka; Iwamoto, Naoki

    2000-01-01

    The kinetics of negatively charged kaon condensation in the early stages of a newly born neutron star is considered. The thermal kaon process, in which kaons are thermally produced by nucleon-nucleon collisions, is found to be dominant throughout the equilibration process. Temporal changes of the order parameter of the condensate and the number densities of the chemical species are obtained from the rate equations, which include the thermal kaon reactions as well as the kaon-induced Urca and the modified Urca reactions. It is shown that the dynamical evolution of the condensate is characterized by three stages: the first, prior to establishment of a condensate, the second, during the growth and subsequent saturation of the condensate, and the third, near chemical equilibrium. The connection between the existence of a soft kaon mode and the instability of the noncondensed state is discussed. Implications of the nonequilibrium process on the possible delayed collapse of a protoneutron star are also mentioned.

  4. KEK workshop on kaon, muon and neutrino physics: summary

    Energy Technology Data Exchange (ETDEWEB)

    Bryman, D. [TRIUMF, Vancouver, BC (Canada)

    1998-02-01

    A broad range of current work and future possibilities associated with the interactions and properties of kaons, muons and neutrinos was discussed at the workshop with particular emphasis on possibilities for the Japanese Hadron Facility. The recent evidence for the flavor changing neutral current reaction K{sup +} {yields} {pi}{sup +}{nu}{nu}-bar was presented along with prospects for future work. New experiments at BNL, KEK and Fermilab are being developed to study the especially attractive CP-violating channel K{sub L}{sup 0} {yields} {pi}{sup 0}{nu}{nu}-bar. Very sensitive searches for lepton flavor violation in muon decays and muon capture, and measurements aiming at uncovering non-standard model T-violating effects in K{sub {mu}3} decay were also discussed. Several neutrino experiments continue to observe deficits in rates relative to expectations, possibly indicating evidence for oscillations, and promising new initiatives such at the K2K project at KEK are in the works to explore these matters further. Many of the issues raised at the workshop are relevant to the search for an understanding of the three generation spectrum of quarks and leptons i.e. the generation puzzle. (author)

  5. Extraction of kaon production cross-sections in HARP

    CERN Document Server

    Schroeter, Raphael; Blondel, Alain; Cervera Villanueva, Anselmo

    Precise measurements of secondary yields in hadron-nucleus collisions in the few GeV/c region are relevant to several areas of particle physics, particularly experimental neutrino physics. In particular, measurements made at HARP can have a direct impact on the detailed understanding of the neutrino fluxes of several accelerator-based neutrino experiments, including the K2K experiment in Japan and MiniBooNE and SciBooNE at Fermilab. HARP took data with these exact beam energies and target materials using both thin and thick targets. Strange particle production in the forward direction must be well known when trying to determine the ve background in a vµ beam, since Ke3 decays of K± and K0L constitute an irreducible background in the search of the vµ -> ve oscillations. This applies particularly to experiments such as MiniBooNE where G4 simulations showed that kaon decays contribute to more than 40% of the total intrinsic ve background of the beam. A complete analysis method has been developed to extract th...

  6. Search for Di-Muon Decays of a Light Scalar Higgs Boson in Radiative Upsilon(1S) Decays

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Vindhyawasini [Indian Inst. of Technology (IIT), Guwahati (India)

    2013-08-01

    We search for di-muon decays of a low-mass Higgs boson (A0) in the fully reconstructed decay chain of Υ(2S, 3S ) → π+π-Υ(1S ), Υ(1S ) → γA0, A0 → μ+μ+. The A0 is predicted by several extensions of the Standard Model (SM), including the Next-to-Minimal Supersymmetric Standard Model (NMSSM). NMSSM introduces a CP-odd light Higgs boson whose mass could be less than 10 GeV/c2. The data samples used in this analysis contain 92.8 × 106 Υ(2S ) and 116.8 × 106 Υ(3S ) events collected by the BABAR detector. The Υ(1S ) sample is selected by tagging the pion pair in the Υ(2S, 3S ) → π+π-Υ(1S ) transitions. We find no evidence for A0 production and set 90% confidence level (C.L.) upper limits on the product branching fraction B(Υ(1S ) → γA0) × B(A0 → μ+μ-) in the range of (0.28 - 9.7) × 10-6 for 0.212 ≤ mA0 ≤ 9.20 GeV/c2. We also combine our results with previous BABAR results of Υ(2S, 3S ) → γA0, A0 → μ+μ- to set limits on the effective coupling ( fΥ) of the b-quark to the A0, f 2 Υ × B(A0 → μ+μ-), at the level of (0.29- 40) × 10-6 for 0.212 ≤ mA0 ≤ 9.2 GeV/c2.

  7. Measurement of Michel Parameters ($\\bar\\eta$, $\\xi\\kappa$) in the radiative leptonic decay of tau at Belle

    CERN Document Server

    Abdesselam, A.

    2017-06-22

    We present the first measurement of the Michel parameters $\\bar{\\eta}$ and $\\xi\\kappa$ in the radiative leptonic decay of the $\\tau$ lepton using 703 f$\\mathrm{b}^{-1}$ of data collected with the Belle detector at the KEKB $e^+e^-$ collider. The Michel parameters are measured by an unbinned maximum likelihood fit to the kinematic information of $e^+e^-\\rightarrow\\tau^+\\tau^-\\rightarrow (\\pi^+\\pi^0 \\bar{\

  8. Loop corrections to pion and kaon neutrinoproduction

    CERN Document Server

    Siddikov, Marat

    2016-01-01

    In this paper we study the next-to-leading order corrections to deeply virtual pion and kaon production in neutrino experiments. We estimate these corrections in the kinematics of the Minerva experiment at FERMILAB, and find that they are sizable and increase the leading order cross-section by up to a factor of two. We provide a code, which can be used for the evaluation of the cross-sections, taking into account these corrections and employing various GPD models.

  9. CALCULATION OF KAON ELECTROMAGNETIC FORM FACTOR

    Institute of Scientific and Technical Information of China (English)

    WANG ZHI-GANG; WAN SHAO-LONG; WANG KE-LIN

    2001-01-01

    The kaon meson electromagnetic form factor is calculated in the framework of coupled Schwinger-Dyson and Bethe-Salpeter formulation in simplified impulse approximation (dressed vertex) with modified fiat-bottom potential,which is a combination of the flat-bottom potential taking into consideration the infrared and ultraviolet asymptotic behaviours of the effective quark-gluon coupling. All the numerical results give a good fit to experimental values.

  10. Direct test of time-reversal symmetry in the entangled neutral kaon system at a \\phi-factory

    CERN Document Server

    Bernabeu, J; Villanueva-Perez, P

    2013-01-01

    We present a novel method to perform a direct T (time reversal) symmetry test in the neutral kaon system, independent of any CP and/or CPT symmetry tests. This is based on the comparison of suitable transition probabilities, where the required interchange of in out states for a given process is obtained exploiting the Einstein-Podolsky-Rosen correlations of neutral kaon pairs produced at a \\phi-factory. In the time distribution between the two decays, we compare a reference transition like the one defined by the time ordered decays (l^-,\\pi\\pi) with the T -conjugated one defined by (3\\pi^0, l^+). With the use of this and other T conjugated comparisons, the KLOE-2 experiment at DAFNE could make a significant test.

  11. Investigation of photoneutron and capture gamma-ray production in Pb and W under irradiation from 16N decay radiation

    Science.gov (United States)

    Kebwaro, Jeremiah Monari; Zhao, Yaolin; He, Chaohui

    2015-09-01

    Lead and tungsten are potential alternative materials for shielding reactor ex-core components with high 16N activity when available space limits application of concrete. Since the two materials are vulnerable to photonuclear reactions, the nature and intensity of the secondary radiation resulting from (γ,n) and (n,γ) reactions when 16N decay radiation interact with these materials need to be well known for effective shielding design. In this study the MCNP code was used to calculate the photoneutron and capture gamma-ray spectra in the two materials when irradiated by 16N decay radiation. It was observed that some of the photoneutrons generated in the two materials lie in the low-energy range which is considered optimum for (n,γ) reactions. Lead is more transparent to the photoneutrons when compared to tungsten. The calculations also revealed that the bremsstrahlung generated by the beta spectrum was not sufficient to trigger any additional photoneutrons. Both energetic and less energetic capture gamma-rays are observed when photoneutrons interact with nuclei of the two materials. Depending on the strength of the 16N source term, the secondary radiation could affect the effectiveness of the shield and need to be considered during design.

  12. Possibilities for Lorentz violation in nonleptonic decays

    NARCIS (Netherlands)

    Keri Vos, K.; Wilschut, H.W.; Timmermans, R.G.E.

    2015-01-01

    The weak interaction offers an interesting portal to search for Lorentz symmetry breaking. We explore the possibilities to study Lorentz violation in nonleptonic decays, focusing on the recent measurement of the KLOE collaboration of the directional dependence of the lifetime of the neutral kaon

  13. Rare meson decays into very light neutralinos

    Energy Technology Data Exchange (ETDEWEB)

    Dreiner, H.K.; Grab, S. [Bonn Univ. (Germany). Bethe Center for Theoretical Physics und Physikalisches Inst.; Koschade, D. [RWTH Aachen Univ. (Germany). Inst. fuer Theoretische Physik; London Univ. (United Kingdom). Centre for Reserach in String Theory; Kraemer, M.; O' Leary, B. [RWTH Aachen Univ. (Germany). Inst. fuer Theoretische Physik; Langenfeld, U. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2009-05-15

    We investigate the bounds on the mass of the lightest neutralino from rare meson decays within the MSSM with and without minimal flavor violation. We present explicit formulae for the two-body decays of mesons into light neutralinos and perform the first complete calculation of the loop-induced decays of kaons to pions and light neutralinos and B mesons to kaons and light neutralinos. We find that the supersymmetric branching ratios are strongly suppressed within the MSSM with minimal flavor violation, and that no bounds on the neutralino mass can be inferred from experimental data, i.e. a massless neutralino is allowed. The branching ratios for kaon and B meson decays into light neutralinos may, however, be enhanced when one allows for non-minimal flavor violation. We find new constraints on the MSSM parameter space for such scenarios and discuss prospects for future kaon and B meson experiments. Finally, we comment on the search for light neutralinos in monojet signatures at the Tevatron and at the LHC. (orig.)

  14. Gray-Tone Lithography Implementation of Drexhage's Method for Calibrating Radiative and Nonradiative Decay Constants of Fluorophores

    CERN Document Server

    Kwadrin, Andrej; 10.1021/jp3048423

    2013-01-01

    We present a straightforward method to realize non-planar dielectric structures with a controlled height profile for use in calibration of fluorophores. Calibration of fluorescence quantum efficiency and intrinsic radiative and nonradiative decay rates of emitters is possible by using changes in the local density of optical states, provided one can control the emitter-surface distance with nanometer accuracy. We realize a method that is accurate yet fast to implement. We fabricate PMMA wedges (4 mm x 4 mm x 2 \\mu m) by gray-tone UV-lithography of Shipley S1813G2. Its applicability as dielectric spacer is demonstrated in Drexhage experiments for three different emitters in the visible and near-infrared wavelength regime. The decay-rate dependence of the fluorescent state of emitters on the distance to a silver mirror is observed and compared to calculations based on the local density of states. Quantitative values for (non)radiative decay rates and quantum efficiencies are extracted. Furthermore, we discuss ho...

  15. An amplitude analysis of the pi0pi0 system produced in radiative J/psi decays

    Science.gov (United States)

    Bennett, Jake Vernon

    Despite many years of study, a complete understanding of the interactions of quarks and gluons within hadronic states remains elusive. Quantum Chromodynamics (QCD) has long predicted the possibility of states in which gluonic excitations can contribute to the characteristics of the state (a hybrid) or even take the place of constituent quarks altogether (a glueball), yet no incontrovertible evidence yet exists. This is partially due to the nature of the low mass spectrum, in which broad, overlapping states make experimental methods challenging. Recent technological improvements and high statistics data sets now enable a rigorous study of regions in which experimentalists may perform fundamental tests of QCD. This dissertation presents one such study, focusing on the pi 0pi0 spectrum. Particular emphasis is placed on the scalar meson spectrum (JPC = 0++), wherein the lightest glueball state is expected. An amplitude analysis of the pi0pi0 system produced in radiative J/psi decays is presented. A mass independent analysis of the (1.3106 +/- 0.0072) x 10 9 J/psi decays collected by the BESIII detector at BEPCII in Beijing, China is repeated under different model assumptions and experimental conditions. Additionally, the branching ratio of radiative J/psi decays to pi0pi0 is measured to be (1.147+/-0.002+/-0.042) x 10-3, where the first error is statistical and the second is systematic. This is the first measurement of this reaction.

  16. Measurements of Direct CP Violation, CPT Symmetry, and Other Parameters in the Neutral Kaon System

    Energy Technology Data Exchange (ETDEWEB)

    Worcester, Elizabeth Turner [Univ. of Chicago, IL (United States)

    2007-12-01

    The authors present precision measurements of the direct CP violation parameter, Re(ϵ'/ϵ), the kaon parameters, Δm and τS, and the CPT tests, Φ± and ΔΦ, in neutral kaon decays. These results are based on the full dataset collected by the KTeV experiment at Fermi National Accelerator Laboratory during 1996, 1997, and 1999. This dataset contains ~ 15 million K → π0π0 decays and ~ 69 million K → π+π- decays. They describe significant improvements to the precision of these measurements relative to previous KTeV analyses. They find Re(ϵ'/ϵ = [19.2 ± 1.1(stat) ± 1.8(syst)] x 10-4, Δm = (5265 ± 10) x 106 hs-1, and τS = (89.62 ± 0.05) x 10-12 s. They measure Φ± = (44.09 ± 1.00)° and ΔΦ = (0.29 ± 0.31)°; these results are consistent with CPT symmetry.

  17. Isospin breaking and radiative corrections in K{sub l4} decays; Brisure d'isospin et corrections radiatives au processus K{sub l4}

    Energy Technology Data Exchange (ETDEWEB)

    Cuplov, V

    2004-04-15

    This thesis is dedicated to the impact of electromagnetic corrections on the decays of K{sub l4}. 2 types of electromagnetic contributions have to be considered: first the exchange of virtual photons and secondly the non-perturbative part of meson-photon interactions. We have also considered the effects of isospin breaking. We have shown that the isospin breaking and the electromagnetic corrections affect K{sub l4} decays in the neutral and mixed channels (respectively by 8% and -2%), while the charged channel is unaffected. It also appears that the tree approximation for the computation of the decay rates, is not accurate enough to explain experimental data. In the second part of this work, we give the analytical expressions of the F and G form factors associated with the amplitude of the K{sub l4} process in the charged mode. Infra-red divergencies counterbalance each other in the decay rates calculation when we consider the process K{sub l4{gamma}} where 1 photon is emitted with an energy below the sensitivity of the detector. We have found that the calculation in one loop order represents 75% of the measured value. The impact of radiative corrections is about 0.9% while the isospin breaking effect is about 1.6 per cent.

  18. Non-radiative decay of a dipole emitter close to a metallic nanoparticle: Importance of higher-order multipole contributions

    CERN Document Server

    Moroz, Alexander

    2009-01-01

    The contribution of higher-order multipoles to radiative and non-radiative decay of a single dipole emitter close to a spherical metallic nanoparticle is re-examined. Taking a Ag spherical nanoparticle (AgNP) with the radius of 5 nm as an example, a significant contribution (between 50% and 101% of the total value) of higher-order multipoles to non-radiative rates is found even at the emitter distance of 5 nm from the AgNP surface. On the other hand, the higher-order multipole contribution to radiative rates is negligible. Consequently, a dipole-dipole approximation can yield only an upper bound on the apparent quantum yield. In contrast, the non-radiative rates calculated with the quasistatic Gersten and Nitzan method are found to be in much better agreement with exact electrodynamic results. Finally, the size corrected metal dielectric function is shown to decrease the non-radiative rates near the dipolar surface plasmon resonance.

  19. Measurement of the absolute branching ratio of the K+→π+π−π+(γ decay with the KLOE detector

    Directory of Open Access Journals (Sweden)

    D. Babusci

    2014-11-01

    Full Text Available The absolute branching ratio of the K+→π+π−π+(γ decay, inclusive of final-state radiation, has been measured using ∼17 million tagged K+ mesons collected with the KLOE detector at DAΦNE, the Frascati ϕ-factory. The result is:BR(K+→π+π−π+(γ=0.05565±0.00031stat±0.00025syst a factor ≃ 5 more precise with respect to the previous result. This work completes the program of precision measurements of the dominant kaon branching ratios at KLOE.

  20. Analysis of the radiative decays $\\Sigma_Q \\to \\Lambda_Q \\gamma$ and $\\Xi^\\prime_Q \\to \\Xi_Q \\gamma$ in light cone sum rules

    CERN Document Server

    Aliev, T M; Savcı, M

    2016-01-01

    The light cone sum rules method is used in studying the radiative decays $\\Sigma_Q \\to \\Lambda_Q \\gamma$ and $\\Xi^\\prime_Q \\to \\Xi_Q \\gamma$. Firstly, the sum rules for the form factor $F_2(Q^2=0)$ responsible for these transitions is constructed. Using this result the decay widths of the above--mentioned decays are calculated and analyzed. A comparison of our predictions on the decay widths of considered transitions with the predictions of the other approaches is presented.

  1. Exclusive weak radiative Higgs decays in the standard model and beyond

    Science.gov (United States)

    Alte, Stefan; König, Matthias; Neubert, Matthias

    2016-12-01

    We perform a detailed study of the exclusive Higgs decays h → MZ and h → MW, where M is a pseudoscalar or vector meson, using the QCD factorization approach. We allow for the presence of new-physics effects in the form of modified Higgs couplings to gauge bosons and fermions, including the possibility of flavor-changing Higgs couplings. We show that the decays h → VZ exhibit a strong sensitivity to the effective CP-even and CP-odd hγZ couplings. When combined with a measurement of the h → γZ decay rate, this can be used to extract these couplings up to a sign ambiguity in the CP-odd coefficient. Some of the h → MW decay modes can be used to probe for flavor-violating Higgs couplings involving the top quark.

  2. Exclusive Weak Radiative Higgs Decays in the Standard Model and Beyond

    CERN Document Server

    Alte, Stefan; Neubert, Matthias

    2016-01-01

    We perform a detailed study of the exclusive Higgs decays $h\\to MZ$ and $h\\to MW$, where $M$ is a pseudoscalar or vector meson, using the QCD factorization approach. We allow for the presence of new-physics effects in the form of modified Higgs couplings to gauge bosons and fermions, including the possibility of flavor-changing Higgs couplings. We show that the decays $h\\to VZ$ exhibit a strong sensitivity to the effective CP-even and CP-odd $h\\gamma Z$ couplings. When combined with a measurement of the $h\\to\\gamma Z$ decay rate, this can be used to extract these couplings up to a sign ambiguity in the CP-odd coefficient. Some of the $h\\to MW$ decay modes can be used to probe for flavor-violating Higgs couplings involving the top quark.

  3. Radiative decays of light vector mesons in a quark level linear sigma model

    CERN Document Server

    Napsuciale, M; Alvarado-Anell, E

    2003-01-01

    We calculate the P0 to gamma gamma, V0 to P0 gamma and V0to V'0 gamma gamma decays in the framework of a U(3)xU(3) linear sigma model which includes constituent quarks. For the first two decays this approach improves results based on the anomalous Wess-Zumino term, with contributions due to SU(3) symmetry breaking and vector mixing. The phi to (omega,rho) gamma gamma decays are dominated by resonant eta' exchange . Our calculation for the later decays improves and update similar calculations in the -closely related- framework of vector meson dominance. We obtain BR(phi to rho gamma gamma)=2.5x10^{-5} and BR(phi to omega gamma gamma)=2.8x10^{-6} within the scope of the high-luminosity phi factories.

  4. The diffusive instability of kaon condensate in neutron star matter

    CERN Document Server

    Kubis, S

    2004-01-01

    The beta equilibrated dense matter with kaon condensate is analyzed with respect to extended stability conditions including charge fluctuations. This kind of the diffusive instability, appeared to be common property in the kaon condensation case. Results for three different nuclear models are presented.

  5. Observation of $\\psi(4415)\\to D \\bar D{}^{*}_2(2460)$ decay using initial-state radiation

    CERN Document Server

    Pakhlova, G; Aihara, H; Arinstein, K; Aulchenko, V; Aushev, T; Bakich, A M; Balagura, V; Barberio, E; Bedny, I; Belous, K S; Bitenc, U; Bondar, A; Bracko, M; Brodzicka, J; Browder, T E; Chen, A; Chen, W T; Cheon, B G; Chiang, C C; Chistov, R; Cho, I S; Choi, Y; Dalseno, J; Danilov, M; Dash, M; Drutskoy, A; Eidelman, S; Epifanov, D; Gabyshev, N; Golob, B; Ha, H; Haba, J; Hayasaka, K; Hazumi, M; Heffernan, D; Hoshi, Y; Hou, W S; Hsiung, Y B; Hyun, H J; Inami, K; Ishikawa, A; Ishino, H; Itoh, R; Iwasaki, M; Iwasaki, Y; Joshi, N J; Kah, D H; Kang, J H; Kawasaki, T; Kibayashi, A; Kichimi, H; Kim, H J; Kim, H O; Kim, Y J; Kinoshita, K; Korpar, S; Krizan, P; Krokovny, P; Kumar, R; Kuo, C C; Kuzmin, A; Kwon, Y J; Lange, J S; Lee, M J; Lee, S E; Lesiak, T; Lin, S W; Liventsev, D; Mandl, F; Marlow, D; McOnie, S; Medvedeva, T; Miyake, H; Mizuk, R; Mohapatra, D; Moloney, G R; Nagasaka, Y; Nakano, E; Nakao, M; Nakazawa, H; Nishida, S; Nitoh, O; Ogawa, S; Ohshima, T; Okuno, S; Olsen, S L; Ozaki, H; Pakhlov, P; Park, H; Park, K S; Peak, L S; Pestotnik, R; Piilonen, L E; Poluektov, A; Sakai, Y; Schneider, O; Schwanda, C; Senyo, K; Shapkin, M; Shen, C P; Shibuya, H; Shiu, J G; Shwartz, B; Singh, J B; Somov, A; Stanic, S; Sumiyoshi, T; Takasaki, F; Tamai, K; Tanaka, M; Taylor, G N; Teramoto, Y; Tikhomirov, I; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Usov, Yu; Varner, G; Vinokurova, A; Wang, C H; Wang, M Z; Wang, P; Wang, X L; Watanabe, Y; Won, E; Yabsley, B D; Yamaguchi, A; Yamashita, Y; Yamauchi, M; Yuan, C Z; Zhang, C C; Zhang, L M; Zhang, Z P; Zhilich, V; Zhulanov, V; Zupanc, A

    2007-01-01

    We report the first observation of the $\\psi(4415)$ resonance in the reaction $\\e^+e^-\\to D^0 D^-\\pi^+$ and a measurement of its cross section in the center-of-mass energy range $4.0\\mathrm{GeV}$ to $5.0\\mathrm{GeV}$ with initial state radiation. From a study of resonant structure in $\\psi(4415)$ decay we conclude that the $\\psi(4415)\\to D^0 D^-\\pi^+$ decay is dominated by $\\psi(4415)\\to D \\bar D{}^{*}_2(2460)$. We obtain $\\mathcal{B}(\\psi(4415)\\to D^0 D^-\\pi^+_{\\mathrm {non-resonant}})/\\mathcal{B}(\\psi(4415)\\to D \\bar D{}^{*}_2(2460)\\to D^0 D^-\\pi^+)<0.22$ at 90% C.L. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 673 $\\mathrm{fb}^{-1}$.

  6. Search for Dimuon Decays of a Light Scalar Boson in Radiative Transitions Υ→γA0

    Science.gov (United States)

    Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Petigura, E.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wang, L.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Ongmongkolku, P.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, T. M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Fioravanti, E.; Franchini, P.; Luppi, E.; Munerato, M.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Guido, E.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Derkach, D.; Firmino da Costa, J.; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Malaescu, B.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Hafner, A.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Schram, M.; Biassoni, P.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Stracka, S.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sonnek, P.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Bonneaud, G. R.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.

    2009-08-01

    We search for evidence of a light scalar boson in the radiative decays of the Υ(2S) and Υ(3S) resonances: Υ(2S,3S)→γA0, A0→μ+μ-. Such a particle appears in extensions of the standard model, where a light CP-odd Higgs boson naturally couples strongly to b quarks. We find no evidence for such processes in the mass range 0.212≤mA0≤9.3GeV in the samples of 99×106 Υ(2S) and 122×106 Υ(3S) decays collected by the BABAR detector at the SLAC PEP-II B factory and set stringent upper limits on the effective coupling of the b quark to the A0. We also limit the dimuon branching fraction of the ηb meson: B(ηb→μ+μ-)<0.9% at 90% confidence level.

  7. Effective Mass of Kaon in Asymmetrici Nuclear Matter

    Institute of Scientific and Technical Information of China (English)

    LiXiguo; GaoYuan; LiuZiyu; ZuoWei

    2003-01-01

    The properties of kaon at very high baryon density has been a fascinating subject since 1986. Of particular importance is the modification of effective mass of antikaon in-medium. This is expected to not only help us to understander the chiral symmetry restoration but also effect the composition and structure of neutron star.. The modification of kaon and antikaon mass in medium might be a new mechanism of production at energies below the threshold. Based on the mean-field approximation to the effective SU(3)L×SU(3)n chiral Lagrangian, the kaon and anti kaon mass in medium, defined as the energy of a kaon (or antikaon) with zero three momentum,are then given by[1

  8. The Kaon Bag Parameter at Physical Mass

    CERN Document Server

    Frison, Julien; Christ, Norman H; Garron, Nicolas; Mawhinney, Robert; Sachrajda, Chris T; Yin, Hantao

    2013-01-01

    We present preliminary results for the calculation of the Kaon Bag parameter $B_K$ in $N_f=2+1$ lattice QCD, using M\\"obius Domain Wall Fermion ensembles generated by the RBC-UKQCD collaboration. This computation is done directly at physical meson masses, so that we do not have to rely on chiral perturbation theory or any other mass extrapolation. In parallel, the four-quark operator is renormalised through the Rome-Southampton technique. Finally, we compare our value with previous results and draw some conclusions about the remaining dominant contributions in our error budget.

  9. Targets for a Neutral Kaon Beam

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Christopher [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-04-01

    A secondary beam of neutral Kaons is under consideration for Hall D at Jefferson Lab to perform spectroscopic studies of hyperons produced by K 0 L particles scattering from proton and deuteron targets. The proposed physics program would utilize the GlueX detector package currently installed in Hall D. This contribution looks at potential targets for use in the new facility, paying close attention to the existing infrastructure of GlueX and Hall D. Unpolarized cryotargets of liquid hydrogen and deuerium, as well as polarized solid targets of protons and deuterons are examined.

  10. Kaon condensation and multi-strange matter

    Science.gov (United States)

    Gazda, D.; Friedman, E.; Gal, A.; Mareš, J.

    2010-04-01

    We report on dynamical calculations of multi- K¯ hypernuclei, which were performed by adding K¯ mesons to particle-stable configurations of nucleons, Λ and Ξ hyperons. The K¯ separation energy as well as the baryonic densities saturate with the number of antikaons. We demonstrate that the saturation is a robust feature of multi- K¯ hypernuclei. Because the K¯ separation energy B does not exceed 200 MeV, we conclude that kaon condensation is unlikely to occur in finite strong-interaction self-bound {N,Λ,Ξ} strange hadronic systems.

  11. Energy and particle flow in three-jet and radiative two-jet events from hadronic Z decays

    Science.gov (United States)

    Acciarri, M.; Adam, A.; Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alcaraz, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Anderson, A. L.; Andreev, V. P.; Angelescu, T.; Antonov, L.; Antreasyan, D.; Alkhazov, G.; Arce, P.; Arefiev, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Bakken, J. A.; Baksay, L.; Ball, R. C.; Banerjee, S.; Banicz, K.; Barillère, R.; Barone, L.; Baschirotto, A.; Basile, M.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Boucham, A.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brigljevic, V.; Brock, I. C.; Brooks, M.; Bujak, A.; Burger, J. D.; Burger, W. J.; Burgos, C.; Busenitz, J.; Buytenhuijs, A.; Bykov, A.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Caria, M.; Carlino, G.; Cartacci, A. M.; Casaus, J.; Castello, R.; Cavallo, N.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Chung, S.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Costantini, S.; Cotorobai, F.; de la Cruz, B.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; DeNotaristefani, F.; DiBitonto, D.; Diemoz, M.; Dimitrov, H. R.; Dionisi, C.; Dittmar, M.; Djambazov, L.; Dorne, I.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duhem, F.; Duinker, P.; Duran, I.; Dutta, S.; Easo, S.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Extermann, P.; Fabbretti, R.; Fabre, M.; Falciano, S.; Favara, A.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Gailloud, M.; Galaktionov, Yu.; Gallo, E.; Ganguli, S. N.; Garcia-Abia, P.; Gentile, S.; Gerald, J.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; Goldstein, J.; Gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M. W.; Gu, C.; Guanziroli, M.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hasan, A.; Hauschildt, D.; He, J. T.; Hebbeker, T.; Hebert, M.; Hervé, A.; Hilgers, K.; Hofer, H.; Hoorani, H.; Hou, S. R.; Hu, G.; Ille, B.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jin, B. N.; Jones, L. W.; de Jong, P.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, D.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirkby, J.; Kirsch, S.; Kittel, W.; Klimentov, A.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krastev, V. R.; Krenz, W.; Kuijten, H.; Kumar, K. S.; Kunin, A.; Ladron de Guevara, P.; Landi, G.; Lanske, D.; Lanzano, S.; Laurikainen, P.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, D. M.; Lee, J. S.; Lee, K. Y.; Leedom, I.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Levtchenko, P.; Li, C.; Lieb, E.; Lin, W. T.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Lohmann, W.; Longo, E.; Lu, W.; Lu, Y. S.; Lubbers, J. M.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, W. G.; MacDermott, M.; Maity, M.; Malgeri, L.; Malik, R.; Malinin, A.; Maña, C.; Mangla, S.; Maolinbay, M.; Marchesini, P.; Marin, A.; Martin, J. P.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McBride, P.; McMahon, T.; McNally, D.; Mele, S.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; Mills, G. B.; Mir, Y.; Mirabelli, G.; Mnich, N.; Möller, M.; Monaco, V.; Monteleoni, B.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nagy, E.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Ostonen, R.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Pevsner, A.; Piccolo, D.; Pieri, M.; Pinto, J. C.; Piroué, P. A.; Pistolesi, E.; Plasil, F.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Produit, N.; Qian, J. M.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Redaelli, M.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Robohm, A.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Röhner, S.; Romero, L.; Rosier-Lees, S.; Rosmalen, R.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubbia, A.; Rubio, J. A.; Rykaczewski, H.; Salicio, J.; Salicio, J. M.; Sanchez, E.; Sanders, G. S.; Santocchia, A.; Sarakinos, M. E.; Sarkar, S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schäfer, C.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Scholz, N.; Schopper, H.; Schotanus, D. J.; Shotkin, S.; Schreiber, H. J.; Shukla, J.; Schulte, R.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Scott, I.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Sheer, I.; Shevchenko, S.; Shi, X. R.; Shumilov, E.; Shoutko, V.; Son, D.; Sopczak, A.; Soulimov, V.; Spartiotis, C.; Spickermann, T.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Strauch, K.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Timellini, R.; Ting, Samuel C. C.; Ting, S. M.; Toker, O.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; Van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vorobyov, An. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, J. C.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Weber, A.; Weber, J.; Weill, R.; Willmott, C.; Wittgenstein, F.; Wright, D.; Wu, S. X.; Wynhoff, S.; Xu, Z. Z.; Yang, B. Z.; Yang, C. G.; Yang, G.; Yao, X. Y.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zemp, P.; Zeng, M.; Zeng, Y.; Zhang, D. H.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.; L3 Collaboration

    1995-02-01

    We report on a detailed study of the energy and particle flow in the event plane of three-jet events (q overlineqg) and radiative two-jet events (q overlineqγ) in hadronic Z decays recorded with the L3 detector. We find a significant decrease in particle and energy density in the angular region between quark and antiquark jets for q overlineqg events as compared with q overlineqγ events. Several QCD model predictions are compared with the observed effect.

  12. Search for dimuon decays of a light scalar boson in radiative transitions Upsilon-->gammaA0.

    Science.gov (United States)

    Aubert, B; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Petigura, E; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Ongmongkolku, P; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Malaescu, B; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; del Amo Sanchez, P; Ben-Haim, E; Bonneaud, G R; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P

    2009-08-21

    We search for evidence of a light scalar boson in the radiative decays of the Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such a particle appears in extensions of the standard model, where a light CP-odd Higgs boson naturally couples strongly to b quarks. We find no evidence for such processes in the mass range 0.212 mu+mu-)<0.9% at 90% confidence level.

  13. Electron correlation effect on radiative decay processes of the core-excited states of Be-like ions

    Energy Technology Data Exchange (ETDEWEB)

    Sang, Cuicui, E-mail: sangcc@126.com [Department of Physics, Qinghai Normal University, Xining 810001 (China); Li, Kaikai [College of Forensic Science, People' s Public Security University of China, Beijing 100038 (China); Sun, Yan; Hu, Feng [School of Mathematic and Physical Science, Xuzhou Institute of Technology, Xuzhou 221400, Jiangsu (China)

    2016-07-15

    Highlights: • Radiative rates of the states 1s2s{sup 2}2p and 1s2p{sup 3} with Z = 8–54 are studied. • Electron correlation effect on the radiative transition rates is studied. • Forbidden transitions are explored. - Abstract: Energy levels and the radiative decay processes of the core-excited configurations 1s2s{sup 2}2p and 1s2p{sup 3} of Be-like ions with Z = 8–54 are studied. Electron correlation effect on the energy levels and the radiative transition rates are studied in detail. Except for E1 radiative transition rates, the E2, M1 and M2 forbidden transitions are also explored. Further relativistic corrections from the Breit interaction, quantum electrodynamics and the finite nuclear size are included in the calculations to make the results more precise. Good agreement is found between our results and other theoretical data.

  14. Constraining |V(td)|/|V(ts)| Using Radiative Penguin B -> V(K*/rho/omega)gamma Decays

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Ping; /Wisconsin U., Madison

    2006-03-08

    Exclusive radiative penguin B decays, B {yields} (K*{sup 0}/K*{sup +}) and B {yields} ({rho}/{omega}){gamma}, are flavor-changing neutral-current (FCNC) processes. Studies of these decays are of special interest in testing Standard Model (SM) predictions and searching for other beyond-the-SM FCNC interactions. Using 89 x 10{sup 6} B{bar B} pairs from BABAR, we measure the branching fraction ({Beta}), CP-asymmetry ({Alpha}), and isospin asymmetry ({Delta}{sub 0-}) of B {yields} (K*{sup 0}/K*{sup +}){gamma} as follows: {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = 3.92 {+-} 0.20(stat.) {+-} 0.24(syst.); {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = 3.87 {+-} 0.28(stat.) {+-} 0.26(syst.); {Alpha}(B {yields} K*{gamma}) = -0.013 {+-} 0.36(stat.) {+-} 0.10(syst.); {Delta}{sub 0-}(B {yields} K*{gamma}) = 0.050 {+-} 0.045(stat.) {+-} 0.028(syst.) {+-} 0.024(R{sup +/0}). The 90% confidence intervals for the CP-asymmetry and the isospin-asymmetry in the B {yields} K*{gamma} decay are given as: -0.074 < {Alpha}(B {yields} K*{gamma}) < 0.049, -0.046 < {Delta}{sub 0-} (B {yields} K*{gamma}) < 0.146. We also search for B {yields} ({rho}/{omega}){gamma} decays using 211 x 10{sup 6} B{bar B} pairs from BABAR. No evidence for these decays is found. We set the upper limits at 90% confidence level for these decays: {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) < 0.4 x 10{sup -6}; {Beta}(B{sup +}{yields} {rho}{sup =}{gamma}) < 1.8 x 10{sup -6}; {Beta}(B{sup 0} {yields} {omega}{gamma}) < 1.0 x 10{sup -6}; {bar {Beta}}(B {yields} ({rho}/{omega}){gamma}) < 1.2 x 10{sup -6}. These results are in good agreement with the SM predictions. The branching fractions of these decays are then used to constrain the ratio |V{sub td}|/|V{sub ts}|.

  15. Prospects for $D^{0} \\rightarrow h^+h^- \\mu^+ \\mu^-$ $(h=K,\\pi)$ decays at LHCb

    CERN Multimedia

    Mitzel, Dominik Stefan

    2017-01-01

    This poster presents the current experimental status and prospects for the search of rare four-body charm decays with final states consisting of two oppositely charged kaons or pions and two oppositely charged muons at LHCb.

  16. Measurement of the photon polarization in radiative $B^0_s$ decays at LHCb

    CERN Multimedia

    Sanchez Mayordomo, Carlos

    2017-01-01

    The photon polarization is studied for the first time in $B_s^0$ decays, using an integrated luminosity of 3 fb$^{-1}$ of proton-proton data recorded by the LHCb experiment. An untagged time-dependent analysis of $B_s^0 \\rightarrow \\phi\\gamma$ decays allows to measure the CPV parameter $\\mathcal{A}^{\\Delta}$, which is sensitive to the left- and right-handed helicity amplitudes. The measured value $\\mathcal{A}^{\\Delta} = -0.98 \\; ^{+0.46}_{-0.52}\\text{(stat.)} ^{+0.23}_{-0.20}\\text{(syst.)}$ is consistent with the Standard Model prediction within two standard deviations. This value can put constraints on the Wilson coefficients $\\mathcal{C}_7$ and $\\mathcal{C}_7^{'}$. With a tagged analysis of the same decay the parameter $S_{\\phi\\gamma}$, also sensitive to the photon polarization, could be measured.

  17. Atomic Radiations in the Decay of Medical Radioisotopes: A Physics Perspective

    Directory of Open Access Journals (Sweden)

    B. Q. Lee

    2012-01-01

    Full Text Available Auger electrons emitted in nuclear decay offer a unique tool to treat cancer cells at the scale of a DNA molecule. Over the last forty years many aspects of this promising research goal have been explored, however it is still not in the phase of serious clinical trials. In this paper, we review the physical processes of Auger emission in nuclear decay and present a new model being developed to evaluate the energy spectrum of Auger electrons, and hence overcome the limitations of existing computations.

  18. Radiative capture studies of the electromagnetic decays of highly excited states

    Energy Technology Data Exchange (ETDEWEB)

    Snover, K.A.

    1980-01-01

    Selected examples of interesting E1, M1, and E2 resonance studies in (p,..gamma..) and (..cap alpha..,..gamma..) reactions are discussed. These include a unique determination of E1 amplitudes in the /sup 12/C(P,..gamma../sub 0/)/sup 13/N reaction, E2 strength in light nuclei, M1 decays to the ground states and to the excited O/sup +/ states of the doubly magic /sup 16/O and /sup 40/Ca nuclei, second harmonic E1 resonances in (p,..gamma..), and M1 ..gamma..-decay of stretched particle-hole states in /sup 16/O and /sup 28/Si.

  19. Radiative decay of mesons in an independent-quark potential model

    Energy Technology Data Exchange (ETDEWEB)

    Barik, N.; Dash, P.C. (Department of Physics, Utkal University, Bhubaneswar 751004 (India)); Panda, A.R. (Department of Physics, Kendrapara College, Kendrapara, Orissa (India))

    1992-11-01

    We investigate in a potential model of independent quarks the {ital M}1 transitions among the low-lying vector ({ital V}) and pseudoscalar ({ital P}) mesons. We perform a static'' calculation of the partial decay widths of twelve possible {ital M}1 transitions such as {ital V}{r arrow}{ital P}{gamma} and {ital P}{r arrow}{ital V}{gamma} within the traditional picture of photon emission by a confined quark and/or antiquark. The model accounts well for the observed decay widths.

  20. Novel nonperturbative approach for radiative B¯0(B¯s0)→J /ψ γ decays

    Science.gov (United States)

    Geng, Li-Sheng; Oset, Eulogio

    2016-07-01

    Radiative B¯ 0(B¯s 0)→J /ψ γ decays provide an interesting case to test our understanding of (non)perturbative QCD and eventually to probe physics beyond the standard model. Recently, the LHCb Collaboration reported an upper bound, updating the results of the BABAR Collaboration. Previous theoretical predictions based on QCD factorization or perturbative QCD have shown large variations due to different treatment of nonfactorizable contributions and meson-photon transitions. In this paper, we report on a novel approach to estimate the decay rates, which is based on a recently proposed model for B decays and the vector meson dominance hypothesis, widely tested in the relevant energy regions. The predicted branching ratios are Br [B¯ 0→J /ψ γ ]=(3.50 ±0.34-0.63+1.12)×10-8 and Br [B¯s 0→J /ψ γ ]=(7.20 ±0.68-1.30+2.31)×10-7 . The first uncertainty is systematic and the second is statistical, originating from the experimental B¯s 0→J /ψ ϕ branching ratio.

  1. Extracting the Kaon Collins function from $e^+e^-$ hadron pair production data

    CERN Document Server

    Anselmino, M; D'Alesio, U; Hernandez, J O Gonzalez; Melis, S; Murgia, F; Prokudin, A

    2015-01-01

    The latest data released by the BaBar Collaboration on azimuthal correlations measured for pion-kaon and kaon-kaon pairs produced in $e^+e^-$ annihilations allow, for the first time, a direct extraction of the kaon Collins functions. These functions are then used to compute the kaon Collins asymmetries in Semi Inclusive Deep Inelastic Scattering processes, which result in good agreement with the measurements performed by the HERMES and COMPASS Collaborations.

  2. Search for heavy neutrino in K{sup -}{yields}{mu}{sup -}{nu}{sub h}({nu}{sub h}{yields}{nu}{gamma}) decay at ISTRA+ setup

    Energy Technology Data Exchange (ETDEWEB)

    Duk, V.A., E-mail: Viacheslav.Duk@cern.ch [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Bolotov, V.N.; Khudyakov, A.A.; Lebedev, V.A.; Makarov, A.I.; Novikov, V.P.; Polyarush, A.Yu. [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Akimenko, S.A.; Britvich, G.I.; Filin, A.P.; Inyakin, A.V.; Kholodenko, S.A.; Leontiev, V.M.; Obraztsov, V.F.; Polyakov, V.A.; Romanovsky, V.I.; Stenyakin, O.V.; Tchikilev, O.G.; Uvarov, V.A.; Yushchenko, O.P. [Institute for High Energy Physics, Protvino (Russian Federation)

    2012-04-04

    Heavy neutrino {nu}{sub h} with m{sub h}{<=}300 MeV/c{sup 2} can be effectively searched for in kaon decays. We put upper limits on a mixing matrix element |U{sub {mu}h}|{sup 2} for radiatively decaying {nu}{sub h} from K{sup -}{yields}{mu}{sup -}{nu}{sub h}({nu}{sub h}{yields}{nu}{gamma}) decay chain in the following parameter region: 30 MeV/c{sup 2}{<=}m{sub h}{<=}80 MeV/c{sup 2}; 10{sup -11} s{<=}{tau}{sub h}{<=}10{sup -9} s. For the whole region |U{sub {mu}h}|{sup 2}{<=}5 Dot-Operator 10{sup -5} for Majorana type of {nu}{sub h} and |U{sub {mu}h}|{sup 2}{<=}8 Dot-Operator 10{sup -5} for the Dirac case.

  3. Search for heavy neutrino in K- →μ-νh (νh → νγ) decay at ISTRA+ setup

    Science.gov (United States)

    Duk, V. A.; Bolotov, V. N.; Khudyakov, A. A.; Lebedev, V. A.; Makarov, A. I.; Novikov, V. P.; Polyarush, A. Yu.; Akimenko, S. A.; Britvich, G. I.; Filin, A. P.; Inyakin, A. V.; Kholodenko, S. A.; Leontiev, V. M.; Obraztsov, V. F.; Polyakov, V. A.; Romanovsky, V. I.; Stenyakin, O. V.; Tchikilev, O. G.; Uvarov, V. A.; Yushchenko, O. P.

    2012-04-01

    Heavy neutrino νh with mh ≲ 300 MeV /c2 can be effectively searched for in kaon decays. We put upper limits on a mixing matrix element |Uμh | 2 for radiatively decaying νh from K- →μ-νh (νh → νγ) decay chain in the following parameter region: 30 MeV /c2 ⩽mh ⩽ 80 MeV /c2; 10-11 s ⩽τh ⩽10-9 s. For the whole region |Uμh | 2 ≲ 5 ṡ10-5 for Majorana type of νh and |Uμh | 2 ≲ 8 ṡ10-5 for the Dirac case.

  4. Seasonal behavior of radon decay products in indoor air and resulting radiation dose to human respiratory tract

    Directory of Open Access Journals (Sweden)

    A.M.A. Mostafa

    2015-01-01

    Full Text Available Most of radiation hazard of indoor radon is largely due to the radon progenies, which are inhaled and deposited in the human respiratory tract. It is essential to evaluate aerodynamic characteristics of the radon progenies, which are either attached or unattached to aerosol particles, because the dose is strongly dependent on the location of deposition in respiratory tract and hence on the aerodynamic characteristics of the aerosol particles. This paper presents the seasonal behavior of radon decay products in indoor air under domestic conditions at Nagoya University, Japan. A low pressure cascade impactor as an instrument for classifying aerosol sizes and imaging plate as a radiation detector have been employed to characterize the activity size distribution of short-lived radon decay products. In parallel, radon and its progenies concentrations were measured. Taking into account the progeny characteristics, the inhalation dose in the different seasons was also estimated based on a lung dose model with the structure that is related to the ICRP66 respiratory tract model. The result evident that, the highest dose 0.22 mSvy−1 was observed during the winter where the highest value of equilibrium equivalent concentration of radon (EEC and lowest value of the activity median aerodynamic diameter (AMAD were found in this season; whereas, the dose in spring appeared to be lowest 0.02 mSvy−1.

  5. D rare/forbidden decays at BESIII

    CERN Document Server

    Zhao, Ming-Gang

    2016-01-01

    In this document we present the latest result on rare/forbidden decays for D mesons at the BESIII experiment. Based on 2.92/fb data taken at the center-of-mass energy 3.773 GeV with the BESIII detector, the flavor-changing neutral current process of neutral D decays into two gammas is searched using a double tag technique, while the decays of charged D decays into a charged kaon/pion plus two electrons/positrons are studied based on a single tag method. The resulting upper limits are still above the Standard Model predictions.

  6. An open quantum system approach to complementarity in neutral kaon interferometry

    CERN Document Server

    de Souza, Gustavo; Varizi, Adalberto D; Nogueira, Edson C; Sampaio, Marcos D

    2016-01-01

    In bipartite quantum systems, entanglement correlations between the parties exerts direct influence in the phenomenon of wave-particle duality. This effect has been quantitatively analyzed in the context of two qubits by M. Jakob and J. Bergou [Optics Communications 283(5) (2010) 827]. Employing a description of the K-meson propagation in free space where its weak decay states are included as a second party, we study here this effect in the kaon-antikaon oscillations. We show that a new quantitative "triality" relation similar to the one considered by Jakob and Bergou holds. In our case, it relates the distinguishability between the decay products states corresponding to the distinct kaon propagation modes $K_S $, $K_L $, the amount of wave-like path interference between these states, and the amount of entanglement given by the reduced von Neumann entropy. The inequality can account for the complementarity between strangeness oscillations and lifetime information previously considered in the literature, there...

  7. Open-quantum-systems approach to complementarity in neutral-kaon interferometry

    Science.gov (United States)

    de Souza, Gustavo; de Oliveira, J. G. G.; Varizi, Adalberto D.; Nogueira, Edson C.; Sampaio, Marcos D.

    2016-12-01

    In bipartite quantum systems, entanglement correlations between the parties exerts direct influence in the phenomenon of wave-particle duality. This effect has been quantitatively analyzed in the context of two qubits by Jakob and Bergou [Opt. Commun. 283, 827 (2010), 10.1016/j.optcom.2009.10.044]. Employing a description of the K -meson propagation in free space where its weak decay states are included as a second party, we study here this effect in the kaon-antikaon oscillations. We show that a new quantitative "triality" relation holds, similar to the one considered by Jakob and Bergou. In our case, it relates the distinguishability between the decay-product states corresponding to the distinct kaon propagation modes KS, KL, the amount of wave-like path interference between these states, and the amount of entanglement given by the reduced von Neumann entropy. The inequality can account for the complementarity between strangeness oscillations and lifetime information previously considered in the literature, therefore allowing one to see how it is affected by entanglement correlations. As we will discuss, it allows one to visualize clearly through the K0-K ¯0 oscillations the fundamental role of entanglement in quantum complementarity.

  8. Search for Light CP-odd Higgs in Radiative Decays of Upsilon(1S)

    CERN Document Server

    Love, W; Méndez, H; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hunt, J M; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Ledoux, J; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Libby, J; Martin, L; Powell, A; Wilkinson, G; Ecklund, K M

    2008-01-01

    We search for a non-SM-like CP-odd Higgs boson (a0_1) with m(a0_1) tau+tau- and a0_1 --> mu+mu- decay channels. No significant signal is found. We obtain upper limits on the product of B(Upsilon(1S)-->gamma a0_1) and B(a0_1-->tau+tau-) or B(a0_1-->mu+mu-). Our tau+tau- results are almost two orders of magnitude more stringent than previous upper limits. Our data provide no evidence for a Higgs state with a mass of 214 MeV decaying to mu+mu-. Existence of such a state was previously proposed as an explanation for 3 Sigma+ --> p mu+mu- events, having mu+mu- masses just above the kinematic threshold, observed by the HyperCP experiment. Our results constrain NMSSM models.

  9. Search for JPC=even++ glueballs in radiative decay of J/Ψ

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Based on the general analysis of decay width and branching ratio of two pseudo scalar meson channels, two sets of discriminants between mesons and glueballs for I=0,JPC=even++ unflavored hadrons with the mass between 1.2 and 2.9 GeV are suggested. Known I=0, JPC=2++, f2(1525) particle is discriminated as a typical meson. The way to discriminate new I=0, JPC=even++ unflavored hadrons is discussed.

  10. Search for JPC = even++ glueballs in radiative decay of J/Ψ

    Institute of Scientific and Technical Information of China (English)

    高崇寿

    2000-01-01

    Based on the general analysis of decay width and branching ratio of two pseudo scalar meson channels, two sets of discriminants between mesons and glueballs for l = 0, J1PC = even++ un-flavored hadrons with the mass between 1.2 and 2.9 GeV are suggested. Known l = 0, JPC = 2++, f2(l525) particle is discriminated as a typical meson. The way to discriminate new l = 0, JPC = even++ unflavored hadrons is discussed.

  11. Sensitivity of the decay $h\\to ZZ^*\\to Zl+l-$ to the Higgs self coupling through radiative corrections

    CERN Document Server

    Castilla-Valdez, H; Moyotl, A; Perez, M A

    2015-01-01

    We study the radiative corrections induced by the triple Higgs boson coupling $hhh$ in the three body decay $h\\to ZZ^*\\to Zl\\bar l$. We show that these corrections are potentially sensitive to the specific value of this coupling in the Standard Model and the Two Higgs Doublet Model. These effects may induce corrections to the integrated decay width of the three-body decay of order few percent and thus open a new window to test the Higgs boson self interaction.

  12. Pion and Kaon Electromagnetic Form Factors

    CERN Document Server

    Bijnens, J; Bijnens, Johan; Talavera, Pere

    2002-01-01

    We study the electromagnetic form factor of the pion and kaons at low-energies with the use of Chiral Perturbation Theory. The analysis is performed within the three flavour framework and at next-to-next-to-leading order. We explain carefully all the relevant consistency checks on the expressions, present full analytical results for the pion form factor and describe all the assumptions in the analysis. From the phenomenological point of view we make use of our expression and the available data to obtain the charge radius of the pion obtaining $_V^\\pi=(0.452+-0.013) fm^2$, as well as the low-energy constant $L_9^r(m_\\rho)= (5.93+-0.43)10^{-3}$. We also obtain experimental values for 3 combinations of order $p^6$ constants.

  13. Strange Baryonic Matter and Kaon Condensation

    Science.gov (United States)

    Gazda, D.; Friedman, E.; Gal, A.; Mareš, J.

    In this contribution we address the question whether kaon condensation could occur in strongly interacting self-bound strange hadronic matter. In our comprehensive dynamical relativistic mean-field (RMF) calculations of nuclear and hypernuclear systems containing several antikaons we found saturation of bar K separation energy as well as the associated nuclear and bar K density distributions upon increasing the number of bar K mesons. The saturation pattern was found to be a universal feature of these multi-strangeness configurations. Since in all cases the bar K separation energy does not exceed 200 MeV, we conclude that bar K mesons do not provide the physical "strangeness" degrees of freedom for self-bound strange hadronic matter.

  14. Multi-kaonic Hypernuclei and Kaon Condensation

    Science.gov (United States)

    Gazda, D.; Friedman, E.; Gal, A.; Mareš, J.

    2011-09-01

    This contribution reports on dynamical, self-consistent calculations of multi-bar K hypernuclei, which were performed by adding antikaons to particle-stable nuclear configurations of nucleons, Λ and Ξ hyperons. Our results show a robust pattern of saturation of the bar K separation energy Bbar K as a function of the number of bar K mesons, with Bbar K bounded from above by 200 MeV. The associated baryon densities saturate at values 2-3 times nuclear-matter density. The main reason for saturation is the repulsion induced by the vector meson fields between bar K mesons, similarly to what was found for multi-bar K nuclei. The calculations confirm that strangeness in finite strong-interaction self-bound systems is realized through hyperons, with no room for kaon condensation.

  15. Current Issues in Kaon Photoelectro-Production off the Nucleon

    CERN Document Server

    Achenbach, Patrick

    2011-01-01

    The electromagnetic kaon production amplitudes associated to Lambda/Sigma hyperons can be described by phenomenological models, most notably by isobar approaches. Experimental data on kaon production have been collected at ELSA, SPring8, GRAAL, LNS Tohoku, and Jefferson Lab in the past, the measurements at Jefferson Lab providing the largest kinematic coverage and statistical significance. However, ambiguities inherent in the models, some data inconsistency in the cross-sections taken at different laboratories, and the problem of missing acceptance in forward direction of the experimental set-ups hinders a reliable extraction of resonance parameters. Predictions for the hypernuclear photo-production cross-section rely on a consistent and comprehensive description of the elementary process at forward kaon angles, where the current strong variation of the models is very unsatisfactory. A number of new experiments are now addressing these issues, among them the charged kaon electro-production programme with the ...

  16. Determination of the pion and kaon structure functions

    Energy Technology Data Exchange (ETDEWEB)

    Aitkenhead, W.; Barton, D.S.; Brandenburg, G.W.; Busza, W.; Dobrowolski, T.; Friedman, J.I.; Kendall, H.W.; Lyons, T.; Nelson, B.; Rosenson, L.; Toy, W.; Verdier, R.; Votta, L.; Chiaradia, M.T.; DeMarzo, C.; Favuzzi, C.; Germinario, G.; Guerriero, L.; LaVopa, P.; Maggi, G.; Posa, F.; Selvaggi, G.; Spinelli, P.; Waldner, F.; Brenner, A.E.; Carey, D.C.; Elias, J.E.; Garbincius, P.H.; Mikenberg, G.; Polychronakos, V.A.; Meunier, R.; Cutts, D.; Dulude, R.S.; Lanou, R.E. Jr.; Massimo, J.T.

    1980-07-21

    Quark structure functions have been extracted from low-p/sub T/ inclusive hadron production data for the pion and kaon with use of the recombination model. n/sup ..pi../=1.0 +- 0.1 and n/sup K/=2.5 +- 0.6 is obtained, where n is the leading (1-x) power of the nonstrange--valence-quark distribution. Both the pion and kaon nonstrange--sea-quark functions have napprox. =3.5.

  17. The Electromagnetic Mass Differences of Pions and Kaons

    CERN Document Server

    Donoghue, J F; Donoghue, John F.; Perez, Antonio F.

    1997-01-01

    We use the Cottingham method to calculate the pion and kaon electromagnetic mass differences with as few model dependent inputs as possible. The constraints of chiral symmetry at low energy, QCD at high energy and experimental data in between are used in the dispersion relation. We find excellent agreement with experiment for the pion mass difference. The kaon mass difference exhibits a strong violation of the lowest order prediction of Dashen's theorem, in qualitative agreement with several other recent calculations.

  18. Collective Flow of A Hyperons within Covariant Kaon Dynamics

    Institute of Scientific and Technical Information of China (English)

    XING Yong-Zhong; ZHU Yu-Lan; WANG Yan-Yan; ZHENG Yu-Ming

    2011-01-01

    @@ The collective flow of ∧ hyperons produced in association with positively charged kaon mesons in nuclear reactions at SIS energies is studied using the quantum molecular dynamics(QMD)model within covariant kaon dynamics Our calculation indicates that both the directed and differential directed flows of ∧s are almost in agreement with the experimental data.This suggest that the covariant kaon dynamics based on the chiral mean field approximation can not only explain the collective flow of kaon mesons,but also give reasonable results for the collective flow of ∧ hyperons at SIS energies.The final-state interaction of ∧ hyperons with dense nuclear matter enhances their directed flow and improves the agreement of their differential directed flow with the experimental data.The influence of the interaction on the ∧ collective flow is more appreciable at large rapidity or transverse momentum region.%The collective How of A hyperons produced in association with positively charged kaon mesons in nuclear reactions at SIS energies is studied using the quantum molecular dynamics (QMD) model within covariant kaon dynamics. Our calculation indicates that both the directed and differential directed Sows of As are almost in agreement with the experimental data. This suggest that the covariant kaon dynamics based on the chiral mean Geld approximation can not only explain the collective flow of kaon mesons, but also give reasonable results for the collective How of A hyperons at SIS energies. The Hnal-state interaction of A hyperons with dense nuclear matter enhances their directed How and improves the agreement of their differential directed How with the experimental data. The influence of the interaction on the A collective How is more appreciable at iarge rapidity or transverse momentum region.

  19. Kaon-nucleon scattering lengths from kaonic deuterium experiments revisited

    CERN Document Server

    Döring, M

    2011-01-01

    We analyse the impact of the recent measurement of kaonic hydrogen X rays by the SIDDHARTA collaboration on the allowed ranges for the kaon-deuteron scattering length in the framework of non-relativistic effective field theory. Based on data from KN scattering only, we predict the kaon-deuteron scattering length A_Kd= (-1.46 + i 1.08) fm, with an estimated uncertainty of about 25% in both the real and the imaginary part.

  20. Measurement of the radiative branching ratio for the Hoyle state using cascade gamma decays

    Directory of Open Access Journals (Sweden)

    Alshahrani B.

    2013-12-01

    Full Text Available A new setup consisting of four 5” by 5” NaI scintillators and an array of particle detectors is being developed. Proton-gamma-gamma coincidences will be measured using the 12C(p, p′12C reaction at 10.5 MeV energy. The new setup will be used for the measurement of the electromagnetic decay rate of the Hoyle state via two E2 transitions. We report the initial experimental results for singles gamma and gamma-proton coincidences through inelastic scattering of protons on a 12C target.

  1. Kaon Thresholds and Two-Flavor Chiral Expansions for Hyperons

    Energy Technology Data Exchange (ETDEWEB)

    Fu-Jiun Jiang, Brian C. Tiburzi, Andre Walker-Loud

    2011-01-01

    Two-flavor chiral expansions provide a useful perturbative framework to study hadron properties. Such expansions should exhibit marked improvement over the conventional three-flavor chiral expansion. Although one can theoretically formulate two-flavor theories for the various hyperon multiplets, the nearness of kaon thresholds can seriously undermine the effectiveness of the perturbative expansion in practice. We investigate the importance of virtual kaon thresholds on hyperon properties, specifically their masses and isovector axial charges. Using a three-flavor expansion that includes SU(3) breaking effects, we uncover the underlying expansion parameter governing the description of virtual kaon thresholds. For spin-half hyperons, this expansion parameter is quite small. Consequently virtual kaon contributions are well described in the two-flavor theory by terms analytic in the pion mass-squared. For spin three-half hyperons, however, one is closer to the kaon production threshold, and the expansion parameter is not as small. Breakdown of SU(2) chiral perturbation theory is shown to arise from a pole in the expansion parameter associated with the kaon threshold. Estimating higher-order corrections to the expansion parameter is necessary to ascertain whether the two-flavor theory of spin three-half hyperons remains perturbative. We find that, despite higher-order corrections, there is a useful perturbative expansion for the masses and isovector axial charges of both spin-half and spin three-half hyperons.

  2. A measurement of the branching ratio of K+-- ->pi+--mu+mu- decays in the Hyper CP experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zyla, Piotr; other HyperCP Collaborators

    2001-11-26

    Large samples of hyperon and kaon decays were collected with the Hyper CP spectrometer during two fixed-target runs at Fermilab. Based on an analysis of 110 million K pm decays from the 1997 data sample we present a branching ratio for K pm right arrow pi pm mu+ mu-. This is the first observation of K- right arrow pi- mu+ mu- decay.

  3. Enhanced electromagnetic dipole moments and radiative decays of massive neutrinos due to the seesaw-induced non-unitary effects

    CERN Document Server

    Xing, Zhi-zhong

    2012-01-01

    In a simple extension of the standard electroweak theory where the phenomenon of lepton flavor mixing is described by a 3x3 unitary matrix V, the electric and magnetic dipole moments of three active neutrinos are suppressed not only by their tiny masses but also by the Glashow-Iliopoulos-Maiani (GIM) mechanism. We show that it is possible to lift the GIM suppression if the canonical seesaw mechanism of neutrino mass generation, which allows V to be slightly non-unitary, is taken into account. In view of current experimental constraints on the non-unitarity of V, we find that the effective electromagnetic dipole moments of three neutrinos and the rates of their radiative decays can be maximally enhanced by a factor of O(10^2) and a factor of O(10^4), respectively. This nontrivial observation reveals an intrinsic and presumably significant correlation between the electromagnetic properties of massive neutrinos and the origin of their small masses.

  4. An amplitude analysis of the $\\pi^{0}\\pi^{0}$ system produced in radiative $J/\\psi$ decays

    CERN Document Server

    Ablikim, M; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Ferroli, R Baldini; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Bondarenko, O; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Cronin-Hennessy, D; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Du, S X; Duan, P F; Eren, E E; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Fava, L; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Geng, C; Goetzen, K; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Han, Y L; Hao, X Q; Harris, F A; He, K L; He, Z Y; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G M; Huang, G S; Huang, H P; Huang, J S; Huang, X T; Huang, Y; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kühn, W; Kupsc, A; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, C H; Li, Cheng; Li, D M; Li, F; Li, G; Li, H B; Li, J C; Li, Jin; Li, K; Li, Lei; Li, P R; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Q; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B J; Liu, C X; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, X X; Liu, Y B; Liu, Z A; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, R Q; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lv, M; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Maas, F E; Maggiora, M; Malik, Q A; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Min, T J; Mitchell, R E; Mo, X H; Mo, Y J; Morales, C Morales; Moriya, K; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Pu, Y N; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Y; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ren, H L; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Santoro, V; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Song, M R Shepherd W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Toth, D; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, X F; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, Z; Xia, L G; Xia, Y; Xiao, D; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H X; Yang, L; Yang, Y; Yang, Y X; Ye, H; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, H W; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, S H; Zhang, X Y; Zhang, Y; Zhang, Y N; Zhang, Y H; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, Li; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2015-01-01

    An amplitude analysis of the $\\pi^{0}\\pi^{0}$ system produced in radiative $J/\\psi$ decays is presented. In particular, a piecewise function that describes the dynamics of the $\\pi^{0}\\pi^{0}$ system is determined as a function of $M_{\\pi^{0}\\pi^{0}}$ from an analysis of the $(1.311\\pm0.011)\\times10^{9}$ $J/\\psi$ decays collected by the BESIII detector. The goal of this analysis is to provide a description of the scalar and tensor components of the $\\pi^0\\pi^0$ system while making minimal assumptions about the properties or number of poles in the amplitude. Such a model-independent description allows one to integrate these results with other related results from complementary reactions in the development of phenomenological models, which can then be used to directly fit experimental data to obtain parameters of interest. The branching fraction of $J/\\psi \\to \\gamma \\pi^{0}\\pi^{0}$ is determined to be $(1.15\\pm0.05)\\times10^{-3}$, where the uncertainty is systematic only and the statistical uncertainty is negl...

  5. Search for Dimuon Decays of a Light Scalar in Radiative Transitions Y(3S) -> gamma A0

    CERN Document Server

    Aubert, B

    2009-01-01

    The fundamental nature of mass is one of the greatest mysteries in physics. The Higgs mechanism is a theoretically appealing way to account for the different masses of elementary particles and implies the existence of a new, yet unseen particle, the Higgs boson. We search for evidence of a light scalar (e.g. a Higgs boson) in the radiative decays of the narrow Y(3S) resonance: Y(3S)->gamma A0, A0->mu+mu-. Such an object appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in a sample of 122*10^6 Y(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction product B(Y(3S)-> gamma A0)*B(A0->mu+mu-) at (0.25-5.2)*10^{-6} in the mass range 0.212mu+mu-)<0.8% at 90% C.L. The results are preliminary.

  6. Factorization, the light-cone distribution amplitude of the B-meson and the radiative decay $B \\to \\gamma l \

    CERN Document Server

    Descotes-Genon, S

    2003-01-01

    We study the radiative decay B -> gamma l nu_l in the framework of QCD factorization. We demonstrate explicitly that, in the heavy-quark limit and at one-loop order in perturbation theory, the amplitude does factorize, i.e. that it can be written as a convolution of a perturbatively calculable hard-scattering amplitude with the (non-perturbative) light-cone distribution amplitude of the B-meson. We evaluate the hard-scattering amplitude at one-loop order and verify that the large logarithms are those expected from a study of the b->u transition in the Soft-Collinear Effective Theory. Assuming that this is also the case at higher orders, we resum the large logarithms and perform an exploratory phenomenological analysis. The questions addressed in this study are also relevant for the applications of the QCD factorization formalism to two-body non-leptonic B-decays, in particular to the component of the amplitude arising from hard spectator interactions.

  7. The $c\\bar c$ interaction above threshold and the radiative decay $X(3872)\\rightarrow J/\\psi\\gamma$

    CERN Document Server

    Badalian, A M; Bakker, B L G

    2015-01-01

    Radiative decays of $X(3872)$ are studied in single-channel approximation (SCA) and in the coupled-channel (CC) approach, where the decay channels $D\\bar D^*$ are described with the string breaking mechanism. In SCA the transition rate $\\tilde{\\Gamma}_2=\\Gamma(2\\,{}^3P_1 \\rightarrow \\psi\\gamma)=71.8$~keV and large $\\tilde{\\Gamma}_1=\\Gamma(2\\,{}^3P_1\\rightarrow J/\\psi\\gamma)=85.4$~keV are obtained, giving for their ratio the value $\\tilde{R_{\\psi\\gamma}}=\\frac{\\tilde{\\Gamma}_2}{\\tilde{\\Gamma}_1}=0.84$. In the CC approach three factors are shown to be equally important. First, the admixture of the $1\\,{}^3P_1$ component in the normalized wave function of $X(3872)$ due to the CC effects. Its weight $c_{\\rm X}(E_{\\rm R})=0.200\\pm 0.015$ is calculated. Secondly, the use of the multipole function $g(r)$ instead of $r$ in the overlap integrals, determining the partial widths. Thirdly, the choice of the gluon-exchange interaction for $X(3872)$, as well as for other states above threshold. If for $X(3872)$ the gluon-e...

  8. Search for Dimuon Decays of a Light Scalar in Radiative Transitions Y(3S) -> gamma A0

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B

    2009-06-02

    The fundamental nature of mass is one of the greatest mysteries in physics. The Higgs mechanism is a theoretically appealing way to account for the different masses of elementary particles and implies the existence of a new, yet unseen particle, the Higgs boson. We search for evidence of a light scalar (e.g. a Higgs boson) in the radiative decays of the narrow {Upsilon}(3S) resonance: {Upsilon}(3S) {yields} {gamma}A{sup 0}, A{sup 0} {yields} {mu}{sup +}{mu}{sup -}. Such an object appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction product {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} {mu}{sup +}{mu}{sup -}) at (0.25 - 5.2) x 10{sup -6} in the mass range 0.212 {<=} m{sub A{sup 0}} {<=} 9.3 GeV. We also set a limit on the dimuon branching fraction of the {eta}{sub b} meson {Beta}({eta}{sub b} {yields} {mu}{sup +}{mu}{sup -}) < 0.8% at 90% C.L. The results are preliminary.

  9. Strong U{sub A}(1) breaking in radiative {eta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, M.; Nemoto, Y.; Oka, M.

    1996-08-01

    We study the {eta} {yields} {gamma}{gamma}, {eta} {yields} {gamma}{mu}{sup -}{mu}{sup +} and {eta} {yields} {pi}{sup 0}{gamma}{gamma} decays using an extended three-flavor Nambu-Jona-Lasinio model that includes the `t Hooft instanton induced interaction. We find that the {eta}-meson mass, the {eta} {yields} {gamma}{gamma}, {eta} {yields} {gamma}{mu}{sup -}{mu}{sup +} and {eta} {yields} {pi}{sup 0}{gamma}{gamma} decay widths are in good agreement with the experimental values when the U{sub A}(1) breaking is strong and the flavor SU(3) singlet-octet mixing angle {theta} is about zero. The calculated {eta}{gamma}{gamma}{sup *} transition form factor has somewhat weaker dependence on the squared four-momentum of the virtual photon. The effects of the U{sub A}(1) anomaly on the scalar quark contents in the nucleon, the {Sigma}{sub {pi}N} and {Sigma}{sub KN} terms and the baryon number one and two systems are also studied. (author)

  10. Measurement of the rate of charm quark pairs produced by radiated gluons in hadronic $Z$ decay

    CERN Document Server

    Park, H K; Vogel, H

    1998-01-01

    We have measured the probability of gluon splitting to charm quark pairs using 1.7 million hadronic Z decays collected in 1994 and 1995 at the L3 detector. Although this process, gluon splitting to charm quark pairs, is one of the basic processes in QCD, it has not been well understood both theoretically and experimentally. Furthermore, the limited knowledge of this process is one of the biggest sources of error in the measurement of the fraction of Z decays to bottom quark pairs (Rb). For this measurement, we have applied two methods to events with a three-jet event topology. One method. relies on tagging charm hadrons by identifying a lepton in the lowest energy jet. Another method uses a neural network technique for identifying events containing gluon splitting into charm quark pairs. Though the first method provides a simple way to tag a charm quark, it is limited by statistics. The second method improves the statistical accuracy by utilizing the entire hadronic event sample. Combining both methods, we me...

  11. Decay dynamics of radiatively coupled quantum dots in photonic crystal slabs

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Mørk, Jesper; Lodahl, Peter

    2011-01-01

    We theoretically investigate the influence of radiative coupling on light emission in a photonic crystal slab structure. The calculation method is based on a formalism that combines the photon Green's tensor with a self-consistent Dyson equation approach and is applicable to a wide range of probl......We theoretically investigate the influence of radiative coupling on light emission in a photonic crystal slab structure. The calculation method is based on a formalism that combines the photon Green's tensor with a self-consistent Dyson equation approach and is applicable to a wide range...

  12. Electromagnetic structure and weak decay of meson K in a light-front QCD-inspired

    CERN Document Server

    Pereira, Fabiano P; Frederico, T; Tomio, Lauro

    2007-01-01

    The kaon electromagnetic (e.m.) form factor is reviewed considering a light-front constituent quark model. In this approach, it is discussed the relevance of the quark-antiquark pair terms for the full covariance of the e.m. current. It is also verified, by considering a QCD dynamical model, that a good agreement with experimental data can be obtained for the kaon weak decay constant once a probability of about 80% of the valence component is taken into account.

  13. Search for Flavor-Changing Neutral-Current Charm Decays

    CERN Document Server

    Aubert, B; Bóna, M; Boutigny, D; Couderc, F; Karyotakis, Yu; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Graugès-Pous, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Y G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Del Amo-Sánchez, P; Barrett, M; Ford, K E; Hart, A J; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schröder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Y I; Solodov, E P; Todyshev, K Y; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, C; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro-Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F R; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flächer, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Stängle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, Gallieno; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Regensburger, J J; Ter-Antonian, R; Wong, Q K; Blount, N L; Brau, J E; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; La Vaissière, C de; Hamon, O; Hartfiel, B L; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Panetta, J; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Safai-Tehrani, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; De Groot, N; Franek, B; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; Vasseur, G; Yéche, C; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Lüth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Vavra, J; Van Bakel, N; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martínez-Vidal, F; Banerjee, S; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R V; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihályi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2006-01-01

    We search for rare FCNC charm decays of the form $X_c^+\\to h^+\\llp$, where $X_c^+$ is a charm hadron, $h$ is a pion, kaon or proton, and $\\ell^{(}{'}^{)}$ is an electron or a muon. In the pion and kaon modes, we study both $D^+$ and $D_s^+$ decays, while in the proton modes we study $\\Lambda_c^+$ decays. Based on a data sample of 288${fb}^{-1}$ of $e^+e^-$ collisions collected by BABAR, we set preliminary 90% confidence level limits between 4 to 40$\\times10^{-6}$ for the branching fractions of the different decay modes. For most decay modes, our analysis provides a significant improvement over previous results.

  14. Photogenerated excitons in plain core CdSe nanocrystals with unity radiative decay in single channel: the effects of surface and ligands.

    Science.gov (United States)

    Gao, Yuan; Peng, Xiaogang

    2015-04-01

    A systematic and reproducible method was developed to study the decay dynamics of an exciton, a photogenerated electron-hole pair, in semiconductor nanocrystals in solution. Results revealed that the excitons in plain core CdSe nanocrystals in either zinc-blende or wurtzite or mixed lattice structures could be reproducibly prepared to decay radiatively in unity quantum yield and in single channel. The single-channel lifetime was found to increase monotonically by increasing size of the CdSe nanocrystals, with zinc-blende ones increasing in a relatively slow pace. Surface inorganic stoichiometry was found to be a sensitive parameter to affect the exciton decay dynamics for all crystal structures with different sizes. Excess Se (Cd) sites on the surface were found to induce short (long) lifetime channels for the excitons. Both types of traps reduced the quantum yield of the radiative decay of the excitons, and the hole traps associated with Se sites were nearly not emissive. With optimal surface inorganic stoichiometry, primary amines were identified as "ideal" organic ligands for CdSe core nanocrystals to achieve unity radiative decay of excitons in single channel in comparison to other types of neutral ligands commonly applied in the field.

  15. J/psi and psi(2S) Radiative Decays to eta_c

    CERN Document Server

    Mitchell, R E; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hunt, J M; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Ledoux, J; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J

    2008-01-01

    Using 24.5 million psi(2S) decays collected with the CLEO-c detector at CESR we present the most precise measurements of magnetic dipole transitions in the charmonium system. We measure B(psi(2S)->gamma eta_c) = (4.32+/-0.16+/-0.60)x10^-3, B(J/psi->gamma eta_c)/B(psi(2S)->gamma eta_c) = 4.59+/-0.23+/-0.64, and B(J/psi->gamma eta_c) = (1.98+/-0.09+/-0.30)%. We observe a distortion in the eta_c line shape due to the photon-energy dependence of the magnetic dipole transition rate that prevents a precision measurement of the eta_c mass and width.

  16. Comprehensive Bayesian analysis of rare (semi)leptonic and radiative [Formula: see text] decays.

    Science.gov (United States)

    Beaujean, Frederik; Bobeth, Christoph; van Dyk, Danny

    The available data on [Formula: see text] decays are in good agreement with the Standard Model when permitting subleading power corrections of about [Formula: see text] at large hadronic recoil. Constraining new-physics effects in [Formula: see text], [Formula: see text], [Formula: see text], the data still demand the same size of power corrections as in the Standard Model. In the presence of chirality-flipped operators, all but one of the power corrections reduce substantially. The Bayes factors are in favor of the Standard Model. Using new lattice inputs for [Formula: see text] form factors and under our minimal prior assumption for the power corrections, the favor shifts toward models with chirality-flipped operators. We use the data to further constrain the hadronic form factors in [Formula: see text] and [Formula: see text] transitions.

  17. Form factors for semi-leptonic and radiative decays of heavy mesons to light mesons

    CERN Document Server

    Stech, B

    1996-01-01

    To know and understand form factors of hadronic currents is of decisive importance for analysing exclusive weak decays. The ratios of different form factors of a given process depend on the relativistic spin structure of initial and final particles. It is shown --- assuming simple properties of the spectator particle --- that these ratios can entirely be expresssed in terms of particle and quark mass parameters. For quark masses large compared to the spectator mass the Isgur-Wise relations follow. The corresponding amplitudes for heavy-to-light transitions show a very similar structure. In particular, the F_0 and A_1 form factors behave again differently from the F_1, A_2, V and T_1 form factors.

  18. Self-consistent solitons for vacuum decay in radiatively generated potentials

    CERN Document Server

    Garbrecht, Bjorn

    2015-01-01

    We use a Green's function approach in order to develop a method for calculating the tunneling rate between radiatively-generated non-degenerate vacua. We apply this to a model that exhibits spontaneous symmetry breaking via the Coleman-Weinberg mechanism, where we determine the self-consistent tunneling configuration and illustrate the impact of gradient effects that arise from accounting for the underlying space-time inhomogeneity.

  19. Self-consistent solitons for vacuum decay in radiatively generated potentials

    Science.gov (United States)

    Garbrecht, Björn; Millington, Peter

    2015-12-01

    We use a Green's function approach in order to develop a method for calculating the tunneling rate between radiatively generated nondegenerate vacua. We apply this to a model that exhibits spontaneous symmetry breaking via the Coleman-Weinberg mechanism, where we determine the self-consistent tunneling configuration and illustrate the impact of gradient effects that arise from accounting for the underlying space-time inhomogeneity.

  20. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is of real particle tracks taken from the CERN 2 m liquid hydrogen bubble chamber and shows the production and decay of a negative omega particle. A negative kaon enters the chamber which decays into many particles, including a negative omega that travels a short distance before decaying into more particles. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that had been heated to boiling point.

  1. Reply to Comments on ``Generation of focused, nonspherically decaying pulses of electromagnetic radiation''

    Science.gov (United States)

    Ardavan, H.

    2000-08-01

    The criticism made by Hannay [preceding Comment, Phys. Rev. E 62, 3008 (2000)] is unfounded since the steps, familiar from the subluminal regime, that are taken in his argument are not mathematically permissible when the distribution pattern of the source is moving and has volume elements that approach the observer with the speed of light and zero acceleration along the radiation direction. In the superluminal regime, the retarded time is a multivalued function of the observation time and so the retarded potential for the radiation from a localized source cannot be represented, as Hannay assumes, by an integral over all space whose integrand entails a differentiable retarded distribution of the source density. Contrary to what is claimed by Hewish [Comment in this issue, Phys. Rev. E 62, 3007 (2000)], moreover, there is no discrepancy between conventional antenna theory and the analysis that appears in Phys. Rev. E 58, 6659 (1998). The characteristics of the new type of emission predicted by this analysis, and received from pulsars, differ from those of the radiation that is produced by known leaky waveguides because there are at present no antennas in which the emitting electric current is both volume-distributed and has the time dependence of a traveling wave with an accelerated superluminal motion.

  2. Test of CPT and Lorentz symmetry in entangled neutral kaons with the KLOE experiment

    CERN Document Server

    :,; Balwierz-Pytko, I; Bencivenni, G; Bloise, C; Bossi, F; Branchini, P; Budano, A; Balkestahl, L Caldeira; Capon, G; Ceradini, F; Ciambrone, P; Curciarello, F; Czerwinski, E; Danè, E; De Leo, V; De Lucia, E; De Robertis, G; De Santis, A; De Simone, P; Di Cicco, A; Di Domenico, A; Di Donato, C; Di Salvo, R; Domenici, D; Erriquez, O; Fanizzi, G; Fantini, A; Felici, G; Fiore, S; Franzini, P; Gajos, A; Gauzzi, P; Giardina, G; Giovannella, S; Graziani, E; Happacher, F; Heijkenskjold, L; Hoistad, B; Jacewicz, M; Johansson, T; Kacprzak, K; Kaminska, D; Kupsc, A; Lee-Franzini, J; Loddo, F; Loffredo, S; Mandaglio, G; Martemianov, M; Martini, M; Mascolo, M; Messi, R; Miscetti, S; Morello, G; Moricciani, D; Moskal, P; Nguyen, F; Palladino, A; Passeri, A; Patera, V; Longhi, I Prado; Ranieri, A; Santangelo, P; Sarra, I; Schioppa, M; Sciascia, B; Silarski, M; Taccini, C; Tortora, L; Venanzoni, G; Wislicki, W; Wolke, M; Zdebik, J

    2014-01-01

    Neutral kaon pairs produced in phi decays in anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis of the CP-violating process phi->K_S K_L->pi+pi-pi+pi- based on 1.7 fb-1 of data collected by the KLOE experiment at the Frascati phi-factory DAFNE. The data are used to perform a measurement of the CPT-violating parameters Delta_amu for neutral kaons in the contest of the Standard Model Extension framework. The parameters measured in the reference frame of the fixed stars are: Delta_ao = (-6.0 +- 7.7_{stat} +- 3.1_{syst}) x 10^{-18} GeV Delta_ax = ( 0.9 +- 1.5_{stat} +- 0.6_{syst}) x 10^{-18} GeV Delta_ay = (-2.0 +- 1.5_{stat} +- 0.5_{syst}) x 10^{-18} GeV Delta_az = ( 3.1 +- 1.7_{stat} +- 0.5_{syst}) x 10^{-18} GeV These are presently the most precise measurements in the quark sector of the Standard Model Extension.

  3. Measurement of the Induced Polarization of Lambda (1116) in Kaon Electroproduction with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Marianna Gabrielyan, Brian Raue, Seema Dhamija, Daniel S. Carman

    2010-08-01

    The CLAS Collaboration is using the p(e,e[prime]K+p)pi- reaction to measure the induced polarization of the electroproduced Lambda(1116). In this experiment a 5.499-GeV electron beam was incident upon an unpolarized liquid-hydrogen target. The CEBAF Large Acceptance Spectrometer (CLAS) was used to detect the scattered electron, the kaon, and the decay proton from the Lambda hyperon. CLAS allowed for a large kinematic acceptance in Q2(0.75<=Q2<=3.5 GeV2) and W(1.6<=W<=3.0 GeV), as well as the kaon center-of-mass scattering angle. The goal is to map out the kinematic dependencies for the induced polarization in order to provide new constraints on models of K-hyperon production. Along with previously published photo- and electroproduction cross sections and polarization observables from CLAS, LEPS, SAPHIR, and GRAAL, these new induced polarization data are needed in coupled-channel analyses to search for previously unobserved s-channel resonances. Preliminary polarization results are presented.

  4. Pair angular correlations for pions, kaons and protons in proton-proton collisions in ALICE

    CERN Document Server

    Zaborowska, Anna

    2014-01-01

    This thesis presents the correlation functions in $\\Delta\\eta\\, \\Delta\\phi$ space for pairs of pions, kaons and protons. The studies were carried out on the set of proton-proton collisions at the centre-of-mass energy $\\sqrt{s}$ = 7 TeV, obtained in ALICE, A Large Ion Collider Experiment at CERN, the European Organization for Nuclear Research. The analysis was performed for two charge combinations (like-sign pairs and unlike-sign pairs) as well as for three multiplicity ranges. Angular correlations are a rich source of information about the elementary particles behaviour. They result in from the interplay of numerous effects, including resonances’ decays, Coulomb interactions and energy and momentum conservation. In case of identical particles quantum statistics needs to be taken into account. Moreover, particles differ in terms of quark content. Kaons, carrying the strange quark obey the strangeness conservation law. In the production of protons baryon number must be conserved. These features are reflected...

  5. Search for a light Higgs boson in the radiative decays of J/psi

    CERN Document Server

    Ablikim, M

    2015-01-01

    We search for a light Higgs boson $A^0$ in the fully reconstructed decay chain of $J/\\psi \\rightarrow \\gamma A^0$, $A^0 \\rightarrow \\mu^+\\mu^-$ using $(225.0\\pm2.8)\\times10^6$ $J/\\psi$ events collected by the BESIII experiment. The $A^0$ is a hypothetical CP-odd light Higgs boson predicted by many extensions of the Standard Model including the Next-to-Minimal Supersymmetric Standard Model. We find no evidence for $A^0$ production and set $90\\%$ confidence-level upper limits on the product branching fraction $\\mathcal{B}(J/\\psi \\rightarrow \\gamma A^0) \\times \\mathcal{B}(A^0 \\rightarrow \\mu^+\\mu^-)$ in the range of $(2.8-471.4)\\times 10^{-8}$ for $0.212 \\le m_{A^0} \\le 3.0$ GeV/$c^2$. The new limits are an order of magnitude below our previous results and can exclude a large portion of the parameter space of the new physics models.

  6. Angular distributions in the radiative decays of the state of charmonium originating from polarized collisions

    Science.gov (United States)

    Wong, Cheuk-Ping; Mok, Alex W. K.; Sit, Wai-Yu

    2015-03-01

    Using the helicity formalism, we calculate the combined angular distribution function of the two gamma photons ( and ) and the electron () in the triple cascade process , when and are arbitrarily polarized. We also derive six different partially integrated angular distribution functions which give the angular distributions of one or two particles in the final state. Our results show that by measuring the two-particle angular distribution of and and that of and , one can determine the relative magnitudes as well as the relative phases of all the helicity amplitudes in the two charmonium radiative transitions and.

  7. Extraction of radiative decay width for the non-strange partner of Theta^+

    CERN Document Server

    Azimov, Ya I; Polyakov, M V; Strakovsky, I I; Azimov, Ya.

    2005-01-01

    Using the results of the GRAAL collaboration on the \\eta photoproduction from the neutron target, we attempt to extract the partial radiative width of the possible new nucleon resonance N^*(1675). The obtained estimates support this resonance to be a very attractive candidate for the non-strange member of the exotic antidecuplet of baryons -- a partner of the \\Theta^+ pentaquark. Our phenomenological value for the transition magnetic moment \\mu(n^* n), appears to be in good agreement with predictions of the Chiral Quark Soliton Model.

  8. The b -> s gamma decay in supergravity with radiatively electroweak breaking

    CERN Document Server

    Díaz, M A

    1994-01-01

    It is analyzed the branching ratio $B(b\\rightarrow s\\gamma)$ in the context of minimal $N=1$ supergravity with radiatively broken electroweak symmetry group. There is a strong dependence on supersymetric parameters, but constraints on the charged Higgs mass in non-supersymmetric models are relaxed, due to large contribution from the chargino/up-type squark sector that interacts destructively with the Standard Model and the charged Higgs contributions. Large suppressions/enhancements of the branching fraction are found for large values of $\\tan\\beta$.

  9. Multi-K¯ nuclei and kaon condensation

    Science.gov (United States)

    Gazda, D.; Friedman, E.; Gal, A.; Mareš, J.

    2008-04-01

    We extend previous relativistic mean-field (RMF) calculations of multi-K¯ nuclei, using vector boson fields with SU(3) PPV coupling constants and scalar boson fields constrained phenomenologically. For a given core nucleus, the resulting K¯ separation energy BK¯, as well as the associated nuclear and K¯-meson densities, saturate with the number κ of K¯ mesons for κ>κsat~10. Saturation appears robust against a wide range of variations, including the RMF nuclear model used and the type of boson fields mediating the strong interactions. Because BK¯ generally does not exceed 200 MeV, it is argued that multi-K¯ nuclei do not compete with multihyperonic nuclei in providing the ground state of strange hadronic configurations and that kaon condensation is unlikely to occur in strong-interaction self-bound strange hadronic matter. Last, we explore possibly self-bound strange systems made of neutrons and K¯0 mesons, or protons and K- mesons, and study their properties.

  10. A Study of Quark Fragmentation Using Kaons Produced in Association with Prompt $D_s^±/D^±$ Mesons

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Niharika Ranjan [Purdue Univ., West Lafayette, IN (United States)

    2012-01-01

    Quarks are considered to be the fundamental constituents of hadronic matter, but they have never been observed as free particles. When quarks are produced at high energy colliders, they quickly form bound colorless states, which then decay to produce the particles observed in experiments. The process by which an initially free quark combines with other quarks to form a hadronic particle is called quark fragmentation and has been described using phenomenological models since quarks were first proposed. Since then, several models have been developed to describe the quark fragmentation phenomenon, and these have been tuned to reproduce many average properties of hadrons produced in high energy collisions. In this dissertation, we describe an analysis that probes the properties of particles produced in association with a hadron containing a charm quark that provides a way, for the first time, to study what is thought of as the second particle produced in the process of heavy quar k fragmentation. Data from proton anti-proton collisions was used to carry out this research, which were collected with the CDF II detector at the Fermilab Tevatron and corresponds to 360/pb-1 of integrated luminosity. We reconstruct $D_s^±$ and $D^±$ mesons, which contain charm quarks, and identify the kaons produced in association with them. The kinematic properties of these kaons are compared with predictions of the fragmentation models implemented in the PYTHIA and HERWIG event generators. We find that kaon production in association with $D_s^±$ mesons is enhanced at levels that are in agreement with the fragmentation models but observe differences in production rates of kaons that are produced later in the fragmentation process.

  11. Perspectives for the measurement of the {chi}{sub c} radiative decay in the ALICE experiment at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Marin, Ana [GSI, Darmstadt (Germany); Gonzalez, Pedro; Ladron de Guevara, Pedro; Serradilla, Eulogio [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain); Lopez Torres, Ernesto [CEADEN, Ciudad Habana (Cuba)

    2009-07-01

    Heavy quarkonia are considered as very promising probes for the deconfinement of the hot and dense matter formed in relativistic heavy-ion collisions. J/{psi} suppression in central heavy-ion collisions beyond expectations from a pure nuclear absorption scenario has been observed at CERN SPS and RHIC energies. Measuring the fraction of J/{psi} resulting from {chi}{sub c} and {psi}{sup '} decays in pp and in heavy-ion collisions would help further understanding the mechanism for the suppression. The LHC will provide pp (PbPb) collisions up to {radical}(s)=14 TeV ({radical}(s{sub NN})= 5.5 TeV). The three experiments (ATLAS, CMS and ALICE) have a large program devoted to quarkonia measurements (J/{psi}, {psi}{sup '}, {upsilon}). Moreover, Monte Carlo studies demonstrate that, with the ALICE detector, it should be possible to reconstruct and separate the {chi}{sub c1} and {chi}{sub c2} in the radiative channel J/{psi}+{gamma}, as two separated peaks. The low momentum photon from the decay is measured by reconstructing in the central barrel the e{sup +}e{sup -} pairs from photons converted mainly in the ITS material. The overall efficiency expected for {chi}{sub c} reconstruction is about 0.9%. For pp collisions, the rate of observable {chi}{sub c}'s is expected to be 1.2 x 10{sup -3} per second, assuming a luminosity of 10{sup 30} cm{sup -2}s{sup -1} and a perfect trigger. An overview of the reconstruction method as well as expected results in pp collisions at LHC is presented.

  12. Kaon Physics at CERN – Recent Results from the NA48/2 and NA62 Experiments

    Directory of Open Access Journals (Sweden)

    Winhart Andreas

    2012-12-01

    Full Text Available This letter presents recent results from the kaon experiments NA48/2 and its successor NA62 at CERN. With samples of 2.5 × 106 Kµ3± and 4.0 × 106 Ke3± events collected by NA48/2 in 2004, precise measurements of the form factors were performed. The Chiral Perturbation Theory was tested through a new study of K± → π±γγ decays based on data taken with minimal trigger conditions. Using the beam line and detector of NA48/2 in the years 2007-2008, NA62 performed a precison measurement of the helicitysuppressed ratio of the charged kaon leptonic decay rates K± → e+ν and K± → μ+ν Using the full data set, which is about ten times larger than the previous world data sample, the total uncertainty on this ratio is only 0.4%, representing a precision test of μ – e lepton universality. Finally, the main stage of the NA62 experiment is presented. The planned measurement of the ultra rare decay K+ → π+ vv¯ $var v$ at 10% precision will provide a powerful test of the Standard Model. The experimental challenges to reach this goal require new detectors with exceptional performances.

  13. Kaon and pion production in centrality selected minimum bias Pb+Pb collisions at 40 and 158A.GeV

    CERN Document Server

    Dinkelaker, Peter

    2009-01-01

    Results on charged kaon and negatively charged pion production and spectra for centrality selected Pb+Pb mininimum bias events at 40 and 158A GeV have been presented in this thesis. All analysis are based on data taken by the NA49 experiment at the accelerator Super Proton Synchrotron (SPS) at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. The kaon results are based on an analysis of the mean energy loss of the charged particles traversing the detector gas of the time projection chambers (TPCs). The pion results are from an analysis of all negatively charged particles h- corrected for contributions from particle decays and secondary interactions. For the dE/dx analysis of charged kaons, main TPC tracks with a total momentum between 4 and 50 GeV have been analyzed in logarithmic momentum log(p) and transverse momentum pt bins. The resulting dE/dx spectra have been fitted by the sum of 5 Gaussians, one for each main particle type (electrons, pions, kaons, pro...

  14. Radiative leptonic decay B-c→τ-(v)τγ in the standard model and the two-Higgs-doublet model

    Institute of Scientific and Technical Information of China (English)

    XIE Zhen-Xing; FENG Guan-Qiu; GUO Xin-Heng

    2010-01-01

    We analyze the radiative leptonic Be decay B-→τ-(v)τγ in the Standard Model and the twoHiggs-doublet model using the non-relativistic constituent quark model.The results confirm that this channel is experimentally promising in view of the large number of Bc mesons which are expected to be produced at future hadron facilities.We also find that this decay is sensitive to the parameters of the two-Higgs-doublet model,and it can be tested in future experiments.

  15. Precision radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying baryon and emitted charged lepton: Effects of the four-body region

    CERN Document Server

    Neri, M; García, A; Martínez, A; Torres, J J; Flores-Mendieta, Ruben

    2007-01-01

    Analytical radiative corrections of order (alpha/pi)(q/M) are calculated for the four-body region of the Dalitz plot of baryon semileptonic decays when the s1.l correlation is present. Once the final result is available, it is possible to exhibit it in terms of the corresponding final result of the three-body region following a set of simple changes in the latter, except for a few exceptions. We cover two cases, a charged and a neutral polarized decaying baryon.

  16. Exclusive hadronic decays of B mesons

    Science.gov (United States)

    Hölscher, Andreas

    1991-06-01

    The recent experimental results on exclusive hadronic decays of B mesons obtained by the ARGUS collaboration are presented in the talk. The results include exclusive hadronic decays involving a b → c transition, namely B decays with a D, D ∗ plus several pions and B decays to J/ψ or ψ' mesons plus Kaons have been studied. The measurements of branching ratios for two-body B decays involving a J/ψ or ψ' meson are of wide interest in the light of proposals for the study of CP violation in future experiments. The branching ratios are compared with the predictions of the model of Bauer, Stech and Wirbel and with a model of A.V. Dobrovolskaya. Using the cleanest decay channels, the masses and mass difference of the charged and neutral B meson are obtained. This mass difference is then compared with the mass splitting in other isospinmultipletts and with theoretical models.

  17. Direct measurements of Ab and Ac using vertex and kaon charge tags at the SLAC detector.

    Science.gov (United States)

    Abe, Koya; Abe, Kenji; Abe, T; Adam, I; Akimoto, H; Aston, D; Baird, K G; Baltay, C; Band, H R; Barklow, T L; Bauer, J M; Bellodi, G; Berger, R; Blaylock, G; Bogart, J R; Bower, G R; Brau, J E; Breidenbach, M; Bugg, W M; Burke, D; Burnett, T H; Burrows, P N; Calcaterra, A; Cassell, R; Chou, A; Cohn, H O; Coller, J A; Convery, M R; Cook, V; Cowan, R F; Crawford, G; Damerell, C J S; Daoudi, M; Dasu, S; de Groot, N; de Sangro, R; Dong, D N; Doser, M; Dubois, R; Erofeeva, I; Eschenburg, V; Etzion, E; Fahey, S; Falciai, D; Fernandez, J P; Flood, K; Frey, R; Hart, E L; Hasuko, K; Hertzbach, S S; Huffer, M E; Huynh, X; Iwasaki, M; Jackson, D J; Jacques, P; Jaros, J A; Jiang, Z Y; Johnson, A S; Johnson, J R; Kajikawa, R; Kalelkar, M; Kang, H J; Kofler, R R; Kroeger, R S; Langston, M; Leith, D W G; Lia, V; Lin, C; Mancinelli, G; Manly, S; Mantovani, G; Markiewicz, T W; Maruyama, T; McKemey, A K; Messner, R; Moffeit, K C; Moore, T B; Morii, M; Muller, D; Murzin, V; Narita, S; Nauenberg, U; Neal, H; Nesom, G; Oishi, N; Onoprienko, D; Osborne, L S; Panvini, R S; Park, C H; Peruzzi, I; Piccolo, M; Piemontese, L; Plano, R J; Prepost, R; Prescott, C Y; Ratcliff, B N; Reidy, J; Reinertsen, P L; Rochester, L S; Rowson, P C; Russell, J J; Saxton, O H; Schalk, T; Schumm, B A; Schwiening, J; Serbo, V V; Shapiro, G; Sinev, N B; Snyder, J A; Staengle, H; Stahl, A; Stamer, P; Steiner, H; Su, D; Suekane, F; Sugiyama, A; Suzuki, A; Swartz, M; Taylor, F E; Thom, J; Torrence, E; Usher, T; Va'vra, J; Verdier, R; Wagner, D L; Waite, A P; Walston, S; Weidemann, A W; Weiss, E R; Whitaker, J S; Williams, S H; Willocq, S; Wilson, R J; Wisniewski, W J; Wittlin, J L; Woods, M; Wright, T R; Yamamoto, R K; Yashima, J; Yellin, S J; Young, C C; Yuta, H

    2005-03-11

    Exploiting the manipulation of the SLAC Linear Collider electron-beam polarization, we present precise direct measurements of the parity-violation parameters A(c) and A(b) in the Z-boson-c-quark and Z-boson-b-quark coupling. Quark-antiquark discrimination is accomplished via a unique algorithm that takes advantage of the precise SLAC Large Detector charge coupled device vertex detector, employing the net charge of displaced vertices as well as the charge of kaons that emanate from those vertices. From the 1996-1998 sample of 400 000 Z decays, produced with an average beam polarization of 73.4%, we find A(c)=0.673+/-0.029(stat)+/-0.023(syst) and A(b)=0.919+/-0.018(stat)+/-0.017(syst).

  18. Direct Measurement of $A_{b}$ using Charged Kaons at the SLD Detector

    CERN Document Server

    Abe, K; Akagi, T; Akimoto, H; Allen, N J; Ash, William W; Aston, D; Baird, K G; Baltay, C; Band, H R; Barakat, M B; Bardon, O; Barklow, Timothy L; Bashindzhagian, G L; Bauer, J M; Bellodi, G; Benvenuti, Alberto C; Bilei, G M; Bisello, D; Blaylock, G; Bogart, J R; Bower, G R; Brau, J E; Breidenbach, M; Bugg, W M; Burke, D; Burnett, T H; Burrows, P N; Byrne, R M; Calcaterra, A; Calloway, D H; Camanzi, B; Carpinelli, M; Cassell, R; Castaldi, R; Castro, A; Cavalli-Sforza, M; Chou, A; Church, E; Cohn, H O; Coller, J A; Convery, M R; Cook, V; Cowan, R F; Coyne, D G; Crawford, G; Damerell, C J S; Danielson, M N; Daoudi, M; De Groot, N; Dell'Orso, R; Dervan, P J; De Sangro, R; Dima, M; Dong, D N; Doser, Michael; Dubois, R; Eisenstein, B I; Erofeeva, I; Eschenburg, V; Etzion, E; Fahey, S; Falciai, D; Fan, C; Fernández, J P; Fero, M J; Flood, K; Frey, R; Gifford, J A; Gillman, T; Gladding, G E; González, S; Goodman, E R; Hart, E L; Harton, J L; Hasuko, K; Hedges, S J; Hertzbach, S S; Hildreth, M D; Huber, J; Huffer, M E; Hughes, E W; Huynh, X; Hwang, H; Iwasaki, M; Jackson, D J; Jacques, P; Jaros, J A; Jiang, Z Y; Johnson, A S; Johnson, J R; Johnson, R A; Junk, T R; Kajikawa, R; Kalelkar, M S; Kamyshkov, Yu A; Kang, H J; Karliner, I; Kawahara, H; Kim, Y D; King, M E; King, R; Kofler, R R; Krishna, N M; Kroeger, R S; Langston, M; Lath, A; Leith, D W G S; Lia, V; Lin, C; Liu, M X; Liu, X; Loreti, M; Lu, A; Lynch, H L; Ma, J; Mahjouri, M; Mancinelli, G; Manly, S L; Mantovani, G C; Markiewicz, T W; Maruyama, T; Masuda, H; Mazzucato, E; McKemey, A K; Meadows, B T; Menegatti, G; Messner, R; Mockett, P M; Moffeit, K C; Moore, T B; Morii, M; Müller, D; Murzin, V S; Nagamine, T; Narita, S; Nauenberg, U; Neal, H A; Nussbaum, M; Oishi, N; Onoprienko, D V; Osborne, L S; Panvini, R S; Park, C H; Pavel, T J; Peruzzi, I; Piccolo, M; Piemontese, L; Pitts, K T; Plano, R J; Prepost, R; Prescott, C Y; Punkar, G D; Quigley, J; Ratcliff, B N; Reeves, T W; Reidy, J; Reinertsen, P L; Rensing, P E; Rochester, L S; Rowson, P C; Russell, J J; Saxton, O H; Schalk, T L; Schindler, R H; Schumm, B A; Schwiening, J; Sen, S; Serbo, V V; Shaevitz, M H; Shank, J T; Shapiro, G; Sherden, D J; Shmakov, K D; Simopoulos, C; Sinev, N B; Smith, S R; Smy, M B; Snyder, J A; Stängle, H; Stahl, A; Stamer, P E; Steiner, H; Steiner, R; Strauss, M G; Su, D; Suekane, F; Sugiyama, A; Suzuki, S; Swartz, M; Szumilo, A; Takahashi, T; Taylor, F E; Thom, J; Torrence, E; Toumbas, N K; Usher, T; Vannini, C; Vavra, J; Vella, E N; Venuti, J P; Verdier, R; Verdini, P G; Wagner, D L; Wagner, S R; Waite, A P; Walston, S; Watts, S J; Weidemann, A W; Weiss, E R; Whitaker, J S; White, S L; Wickens, F J; Williams, B; Williams, D C; Williams, S H; Willocq, S; Wilson, R J; Wisniewski, W J; Wittlin, J L; Woods, M; Word, G B; Wright, T R; Wyss, J; Yamamoto, R K; Yamartino, J M; Yang, X; Yashima, J; Yellin, S J; Young, C C; Yuta, H; Zapalac, G H; Zdarko, R W; Zhou, J

    1999-01-01

    We report a new measurement of A_b using data obtained by SLD in 1997-98. This measurement uses a vertex tag technique, where the selection of a b hemisphere is based on the reconstructed mass of the bottom hadron decay vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and the small and stable SLC beams to obtain a high b-event tagging efficiency and purity of 78% and 97%, respectively. Charged kaons identified by the CRID detector provide an efficient quark-antiquark tag, with the analyzing power calibrated from the data. We obtain a preliminary result of A_b = 0.997

  19. Charged kaon mass measurement using the Cherenkov effect

    Energy Technology Data Exchange (ETDEWEB)

    Graf, N., E-mail: ngraf@umail.iu.ed [Indiana University, Bloomington, IN 47403 (United States); Lebedev, A. [Harvard University, Cambridge, MA 02138 (United States); Abrams, R.J. [University of Michigan, Ann Arbor, MI 48109 (United States); Akgun, U.; Aydin, G. [University of Iowa, Iowa City, IA 52242 (United States); Baker, W. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Barnes, P.D. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Bergfeld, T. [University of South Carolina, Columbia, SC 29201 (United States); Beverly, L. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Bujak, A. [Purdue University, West Lafayette, IN 47907 (United States); Carey, D. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Dukes, C. [University of Virginia, Charlottesville, VA 22904 (United States); Duru, F. [University of Iowa, Iowa City, IA 52242 (United States); Feldman, G.J. [Harvard University, Cambridge, MA 02138 (United States); Godley, A. [University of South Carolina, Columbia, SC 29201 (United States); Guelmez, E.; Guenaydin, Y.O. [University of Iowa, Iowa City, IA 52242 (United States); Gustafson, H.R. [University of Michigan, Ann Arbor, MI 48109 (United States); Gutay, L. [Purdue University, West Lafayette, IN 47907 (United States); Hartouni, E. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2010-03-21

    The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 and 22 ppm yet differ from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 to +63GeV/c. The measured value is 491.3+-1.7MeV/c{sup 2}, which is within 1.4sigma of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.

  20. Charged Kaon Mass Measurement using the Cherenkov Effect

    CERN Document Server

    Graf, N; Abrams, R J; Akgun, U; Aydin, G; Baker, W; Barnes, P D; Bergfeld, T; Beverly, L; Bujak, A; Carey, D; Dukes, C; Duru, F; Feldman, G J; Godley, A; Gülmez, E; Günaydın, Y O; Gustafson, H R; Gutay, L; Hartouni, E; Hanlet, P; Hansen, S; Heffner, M; Johnstone, C; Kaplan, D; Kamaev, O; Kilmer, J; Klay, J; Kostin, M; Lange, D; Ling, J; Longo, M J; Lu, L C; Materniak, C; Messier, M D; Meyer, H; Miller, D E; Mishra, S R; Nelson, K; Nigmanov, T; Norman, A; Onel, Y; Paley, J M; Park, H K; Penzo, A; Peterson, R J; Raja, R; Rajaram, D; Ratnikov, D; Rosenfeld, C; Rubin, H; Seun, S; Solomey, N; Soltz, R; Swallow, E; Schmitt, R; Subbarao, P; Torun, Y; Tope, T E; Wilson, K; Wright, D; Wu, K

    2009-01-01

    The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 ppm and 22 ppm yet differ from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 GeV/c to +63 GeV/c. The measured value is 491.3 +/- 1.7 MeV/c^2, which is within 1.4 sigma of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.

  1. Kaon electroproduction at large four-momentum transfer

    Energy Technology Data Exchange (ETDEWEB)

    Pete Markowitz

    2003-06-16

    Exclusive H(e,e'K)Y data were taken in January, March and April of 2001 at the Jefferson Lab Hall A. The electrons and kaons were detected in coincidence in the hall's two High Resolution Spectrometers (HRS). The kaon arm of the pair had been specifically outfitted with two aerogel Cerenkov threshold detectors, designed to separately provide pion and proton particle identification thus allowing kaon identification. Preliminary data show the cross section's dependence on the invariant mass, W, along with results of systematic studies. Ultimately the data will be used to perform a Rosenbluth Separation as well, separating the longitudinal from the transverse response functions.

  2. Exposing strangeness: Projections for kaon electromagnetic form factors

    Science.gov (United States)

    Gao, Fei; Chang, Lei; Liu, Yu-Xin; Roberts, Craig D.; Tandy, Peter C.

    2017-08-01

    A continuum approach to the kaon and pion bound-state problems is used to reveal their electromagnetic structure. For both systems, when used with parton distribution amplitudes appropriate to the scale of the experiment, Standard Model hard-scattering formulas are accurate to within 25% at momentum transfers Q2≈8 GeV2. There are measurable differences between the distribution of strange and normal matter within the kaons, e.g. the ratio of their separate contributions reaches a peak value of 1.5 at Q2≈6 GeV2. Its subsequent Q2 evolution is accurately described by the hard scattering formulas. Projections for the ratio of kaon and pion form factors at timelike momenta beyond the resonance region are also presented. These results and projections should prove useful in planning next-generation experiments.

  3. Baryon masses at nonzero isospin/kaon density

    CERN Document Server

    Detmold, William

    2013-01-01

    We present a lattice QCD calculation of the ground-state energy shifts of various baryons in a medium of pions or kaons at a single value of the quark mass corresponding to a pion mass of m_\\pi~390 MeV and a kaon mass of m_K~540 MeV, and in a spatial volume V (4fm)^3. All systems are created using a canonical formalism in which quark propagators are contracted into correlation functions of fixed isospin/kaon density. We study four different systems, \\Sigma^+(\\pi^+)^n, \\Xi^0(\\pi^+)^n, p(K^+)^n, and n(K^+)^n, for up to n=11 mesons. From the ground-state energy shifts we extract two- and three-body scattering parameters, as well as linear combinations of low-energy constants appearing in tree-level chiral perturbation theory.

  4. Radiative corrections to W+jet production at hadron colliders with a leptonic decay of the W boson

    Energy Technology Data Exchange (ETDEWEB)

    Kasprzik, Tobias

    2009-08-31

    The production of W bosons and additional jets at hadron colliders is a topic of great phenomenological interest, because such processes have large cross sections and, owing to the clear decay signature of the W boson, can for instance be used to monitor and calibrate the collider's luminosity, as well as for a precise determination of the W-boson mass and width. Thus, a profound theoretical understanding of this process class is mandatory. In order to improve the accuracy of the theoretical predictions, this thesis is devoted to the calculation of the electroweak radiative corrections to the production of one W boson with one associated jet at the LHC and the Tevatron within the Standard Model. Since these corrections are at first evaluated on the parton level in a perturbative approach, we work in the parton model, where the hadronic cross section is obtained by folding the partonic contributions with the parton distribution functions that contain the non-perturbative information of the proton structure and have to be determined by experiment. We provide results for a stable W boson that is produced on its mass shell as well as for an intermediate (off-shell) W boson decaying into a charged lepton and a neutrino. For a consistent calculation of the next-to-leading order corrections, we have to take into account the virtual one-loop contributions, as well as the real bremsstrahlung corrections caused by radiation of one additional photon. Within both contributions, mass singularities appear that have to be treated with care within the numerical evaluation. In the calculation with a stable W boson in the final state, we use the method of phase-space slicing in order to exclude such singularities from the numerical phase-space integration and calculate them analytically in the problematic phase-space regions. For the off-shell calculation, however, we use the more sophisticated dipole subtraction technique to subtract the infrared-singular structures on the

  5. Valence-quark distribution functions in the kaon and pion

    Science.gov (United States)

    Chen, Chen; Chang, Lei; Roberts, Craig D.; Wan, Shaolong; Zong, Hong-Shi

    2016-04-01

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed quarks carry all the meson's momentum at a characteristic hadronic scale and vanish as (1 -x )2 when Bjorken-x →1 . Comparing such distributions within the pion and kaon, it is apparent that the size of S U (3 ) -flavor symmetry breaking in meson parton distribution functions is modulated by the flavor dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulas may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison with experiment which allows us to identify and highlight basic features of measurable pion and kaon valence-quark distributions. We find that whereas roughly two thirds of the pion's light-front momentum is carried by valence dressed quarks at a characteristic hadronic scale; this fraction rises to 95% in the kaon; evolving distributions with these features to a scale typical of available Drell-Yan data produces a kaon-to-pion ratio of u -quark distributions that is in agreement with the single existing data set, and predicts a u -quark distribution within the pion that agrees with a modern reappraisal of π N Drell-Yan data. Precise new data are essential in order to validate this reappraisal and because a single modest-quality measurement of the kaon-to-pion ratio cannot be considered definitive.

  6. Valence-quark distribution functions in the kaon and pion

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen; Chang, Lei; Roberts, Craig D.; Wan, Shaolong; Zong, Hong-Shi

    2016-04-18

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed quarks carry all the meson’s momentum at a characteristic hadronic scale and vanish as ( 1 - x ) 2 when Bjorken- x → 1 . Comparing such distributions within the pion and kaon, it is apparent that the size of S U ( 3 ) -flavor symmetry breaking in meson parton distribution functions is modulated by the flavor dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulas may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison with experiment which allows us to identify and highlight basic features of measurable pion and kaon valence-quark distributions. We find that whereas roughly two thirds of the pion’s light-front momentum is carried by valence dressed quarks at a characteristic hadronic scale; this fraction rises to 95% in the kaon; evolving distributions with these features to a scale typical of available Drell-Yan data produces a kaon-to-pion ratio of u -quark distributions that is in agreement with the single existing data set, and predicts a u -quark distribution within the pion that agrees with a modern reappraisal of π N Drell-Yan data. Precise new data are essential in order to validate this reappraisal and because a single modest-quality measurement of the kaon-to-pion ratio cannot be considered definitive.

  7. Radiation Therapy

    Science.gov (United States)

    ... the area is stitched shut. Another treatment, called proton-beam radiation therapy , focuses the radiation on the ... after radiation treatment ends. Sore mouth and tooth decay. If you received radiation therapy to the head ...

  8. Proton decay and grand unification

    CERN Document Server

    Senjanovic, Goran

    2009-01-01

    I review the theoretical and experimental status of proton decay theory and experiment. Regarding theory, I focus mostly, but not only, on grand unification. I discuss only the minimal, well established SU(5) and SO(10) models, both ordinary and supersymmetric. I show how the minimal realistic extensions of the original Georgi - Glashow model can lead to interesting LHC physics, and I demonstrate that the minimal supersymmetric SU(5) theory is in perfect accord with experiment. Since no universally accepted model has of yet emerged, I discuss the effective operator analysis of proton decay and some related predictions from a high scale underlying theory. A strong case is made for the improvement of experimental limits, or better the search of, two body neutron decay modes into charged kaons and charged leptons. Their discovery would necessarily imply a low energy physics since they practically vanish in any theory with a desert in energies between M_W and M_GUT.

  9. Kaon Eletromagnetic Form Factor in the Light-Front Formalism

    CERN Document Server

    Pereira, F P; Frederico, T; Tomio, L; Pereira, Fabiano P.; Tomio, Lauro

    2005-01-01

    Numerical calculations are performed and compared to the experimental data for the electromagnetic form factor of the kaon, which is extracted from both components of the electromagnetic current, $J^{+}$ and $J^{-}$, with a pseudo-scalar coupling of the quarks to the kaon. In the case of $J^{+}$ there is no pair term contribution in the Drell-Yan frame ($q^{+}=0$). However, for $J^{-}$, the pair term contribution is different from zero and necessary in order to preserve the rotational symmetry of the current. The free parameters are the quark masses and the regulator mass.

  10. Kaon condensation in neutron stars and high density behaviour of nuclear symmetry energy

    CERN Document Server

    Kubis, S

    1999-01-01

    We study the influence of a high density behaviour of the nuclear symmetry energy on a kaon condensation in neutron stars. We find that the symmetry energy typical for several realistic nuclear potentials, which decreases at high densities, inhibits kaon condensation for weaker kaon-nucleon couplings. There exists a threshold coupling above which the kaon condensate forms at densities exceeding some critical value. This is in contrast to the case of rising symmetry energy, as e.g. for relativistic mean field models, when the kaon condensate can form for any coupling at a sufficiently high density. Properties of the condensate are also different in both cases.

  11. Kaon photoproduction from the deuteron in a Regge-plus-resonance approach

    CERN Document Server

    Vancraeyveld, Pieter; Ryckebusch, Jan; Vrancx, Tom

    2012-01-01

    We present a Regge-inspired effective-Lagrangian framework for kaon photoproduction from the deuteron. Quasi-free kaon production is investigated using the Regge-plus-resonance (RPR) elementary operator within the relativistic plane-wave impulse approximation. The RPR model was developed to describe photoinduced and electroinduced charged-kaon production off protons. We show how this elementary operator can be transformed in order to account for the production of neutral kaons from both protons and neutrons. The model results for kaon photoproduction from the deuteron compare favourably to the 2H(g,K)YN data published to date.

  12. Kaon photoproduction from the deuteron in a Regge-plus-resonance approach

    Energy Technology Data Exchange (ETDEWEB)

    Vancraeyveld, P., E-mail: pieter.vancraeyveld@ugent.be [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); De Cruz, L. [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Ryckebusch, J., E-mail: jan.ryckebusch@ugent.be [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Vrancx, T. [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)

    2013-01-02

    We present a Regge-inspired effective-Lagrangian framework for kaon photoproduction from the deuteron. Quasi-free kaon production is investigated using the Regge-plus-resonance (RPR) elementary operator within the relativistic plane-wave impulse approximation. The RPR model was developed to describe photoinduced and electroinduced charged-kaon production off protons. We show how this elementary operator can be transformed in order to account for the production of neutral kaons from both protons and neutrons. The model results for kaon photoproduction from the deuteron compare favourably to the {sup 2}H({gamma},K)YN data published to date.

  13. Kaon identification and the search for heavy neutrinos at NA62

    CERN Document Server

    Newson, Francis; Lazzeroni, Cristina; Goudzovski, Evgueni

    A search for heavy neutrinos in the decay K⁺→μ⁺_h has been performed using the data collected by the NA62-R_K experiment in 2007. The signal event selection is presented, along with an estimate of the expected background in the signal region, obtained by Monte Carlo simulation as well as data driven techniques. This estimate is supported by studies of the detector performance in muon identification efficiency and momentum resolution. Using a sample corresponding to 6x10^7 kaon decays in the fiducial volume, limits of order 10^-^5 have been set on the branching ratio, Br(K^+→μ^+ν_h ), for neutrino masses in the range 275 MeV/c^2 – 375 MeV/c^2, under the assumption that the heavy neutrino does not decay into visible particles inside the detector. In the range 330 MeV/c^2 – 375 MeV/c^2, there are no previous limits from peak searches. Over the rest of the range, the new limits do not improve upon existing results. Improved limits might come from the NA62 experiment designed to measure the branchin...

  14. Precision tests of the J/psi from full lattice QCD: mass, leptonic width and radiative decay rate to eta_c

    CERN Document Server

    Davies, C T H; Dowdall, R J; Koponen, J; Follana, E; Hornbostel, K; Lepage, G P; McNeile, C

    2013-01-01

    We show results from calculations in full lattice QCD of the mass, leptonic width and radiative decay rate to eta_c of the J/psi meson. These provide few % tests of QCD. Another (1.5%) test comes from comparison of time-moments of the vector charmonium correlator with results derived from the experimental values of R(e+e- to hadrons) in the charm region.

  15. An analytical method for estimating the 14N nuclear quadrupole resonance parameters of organic compounds with complex free induction decays for radiation effects studies

    Energy Technology Data Exchange (ETDEWEB)

    Iselin, Louis Henry [Univ. of Florida, Gainesville, FL (United States)

    1992-01-01

    The use of 14N nuclear quadrupole resonance (NQR) as a radiation dosimetry tool has only recently been explored. An analytical method for analyzing 14N NQR complex free induction decays is presented with the background necessary to conduct pulsed NQR experiments. The 14N NQR energy levels and possible transitions are derived in step-by-step detail. The components of a pulsed NQR spectrometer are discussed along with the experimental techniques for conducting radiation effects experiments using the spectrometer. Three data analysis techniques -- the power spectral density Fourier transform, state space singular value decomposition (HSVD), and nonlinear curve fitting (using the downhill simplex method of global optimization and the Levenberg-Marquart method) -- are explained. These three techniques are integrated into an analytical method which uses these numerical techniques in this order to determine the physical NQR parameters. Sample data sets of urea and guanidine sulfate data are used to demonstrate how these methods can be employed to analyze both simple and complex free induction decays. By determining baseline values for biologically significant organics, radiation effects on the NQR parameters can be studied to provide a link between current radiation dosimetry techniques and the biological effects of radiation.

  16. Violation of Bell’s inequality in neutral kaons system

    Indian Academy of Sciences (India)

    Manoj K Samal; Dipankar Home

    2002-08-01

    We show by general considerations that it is not possible to test violation of the existing versions of Bell’s inequality in entangled neutral kaons system using experimentally accessible thin regenerators. We point out the loophole in the recent argument (A Bramon and M Nowakowski, Phys. Rev. Lett. 83, 1 (1999)) that claimed such a test to be possible.

  17. Bell inequality and CP violation in the neutral kaon system

    CERN Document Server

    Bertlmann, Reinhold A; Hiesmayr, B C

    2001-01-01

    For the entangled neutral kaon system we formulate a Bell inequality sensitive to CP violation in mixing. Via this Bell inequality we obtain a bound on the leptonic CP asymmetry which is violated by experimental data. Furthermore, we connect the Bell inequality with a decoherence approach and find a lower bound on the decoherence parameter which practically corresponds to Furry's hypothesis.

  18. Optimization of Experiment Detecting Kaon and Pion Internal Structure

    Science.gov (United States)

    Wacht, Jacob

    2016-09-01

    Pions and kaons are the lightest two-quark systems in Nature. Scientists believe that the rules governing the strong interaction are chirally, symmetric. If this were true, the pion would have no mass. The chiral symmetry is broken dynamically by quark-gluon interactions, giving the pion mass. The pion is thus seen as the key to confirm the mechanism that dynamically generates nearly all of the mass of hadrons and central to the effort to understand hadron structure. The most prominent observables are the meson form factors. Experiments are planned at the 12 GeV Jefferson Lab. An experiment aimed at shedding light on the kaon's internal structure is scheduled to run in 2017. The experimental setup has been optimized for detecting kaons, but it may allow for detecting pions between values of Q2 of 0.4 and 5.5 GeV2. Measurements of the separated pion cross section and exploratory extraction of the pion form factor from electroproduction at low Q2 could be compared to earlier e-pi scattering data, and thus help validating the method. At high Q2, these measurements provide the first L/T separated cross sections and could help guide planned dedicated pion experiments. I will present possible parasitic studies with the upcoming kaon experiment. This work was supported in part by NSF Grant PHY-1306227.

  19. Determination of Transverse Charge Density from Kaon Form Factor Data

    Science.gov (United States)

    Mejia-Ott, Johann; Horn, Tanja; Pegg, Ian; Mecholski, Nicholas; Carmignotto, Marco; Ali, Salina

    2016-09-01

    At the level of nucleons making up atomic nuclei, among subatomic particles made up of quarks, K-mesons or kaons represent the most simple hadronic system including the heavier strange quark, having a relatively elementary bound state of a quark and an anti-quark as its valence structure. Its electromagnetic structure is then parametrized by a single, dimensionless quantity known as the form factor, the two-dimensional Fourier transform of which yields the quantity of transverse charge density. Transverse charge density, in turn, provides a needed framework for the interpretation of form factors in terms of physical charge and magnetization, both with respect to the propagation of a fast-moving nucleon. To this is added the value of strange quarks in ultimately presenting a universal, process-independent description of nucleons, further augmenting the importance of studying the kaon's internal structure. The pressing character of such research questions directs the present paper, describing the first extraction of transverse charge density from electromagnetic kaon form factor data. The extraction is notably extended to form factor data at recently acquired higher energy levels, whose evaluation could permit more complete phenomenological models for kaon behavior to be proposed. This work was supported in part by NSF Grant PHY-1306227.

  20. Proton and kaon timelike form factors from BABAR

    CERN Document Server

    Serednyakov, S I

    2015-01-01

    The latest BABAR results on the proton and kaon timelike form factors (FF) are presented. The special emphasize is made on comparison of the spacelike and timelike FFs and the rise of the proton FF near threshold. The behavior of the cross section of e+e- annihilation into hadrons near the nucleon-antinucleon threshold is discussed.

  1. Observation of charmless hadronic B decays

    CERN Document Server

    Buskulic, Damir; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Juste, A; Martínez, M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Alemany, R; Bazarko, A O; Bonvicini, G; Bright-Thomas, P G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Moneta, L; Oest, T; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Gay, P; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Abbaneo, D; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Konstantinidis, N P; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Bauer, C; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Verdini, P G; Walsh, J; Blair, G A; Bryant, L M; Cerutti, F; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Köksal, A; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, A M; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    Four candidates for charmless hadronic B decay are observed in a data sample of four million hadronic Z decays recorded by the {\\sc aleph} detector at {\\sc lep} . The probability that these events come from background sources is estimated to b e less than $10^{-6}$. The average branching ratio of weakly decaying B hadrons (a mixture of $\\bd$, $\\bs$ and $\\lb$ weighted by their production cross sections and lifetimes , here denoted B) into two long-lived charged hadrons (pions, kaons or protons) is measured to be $\\Br(\\btohh) = \\resultBR$. The relative branching fraction $\\rratio$, where $\\rs$ is the ratio of $\\bs$ to $\\bd$ decays in the sample, is measured to be $\\resultR$. %Branching ratio upper limits are also obtained for a variety In addition, branching ratio upper limits are obtained for a variety of exclusive charmless hadronic two-body decays of B hadrons.

  2. Charmless b-hadrons decays at CDF

    CERN Document Server

    Morello, M J

    2008-01-01

    We present CDF results on the branching fractions and time-integrated direct CP asymmetries for Bd, Bs and Lb decay modes into pairs of charmless charged hadrons (pions, kaons and protons). The data-set for these measurements amounts to 1fb^{-1} of pbar-p collisions at a center of mass energy 1.96TeV. We report on the first observation of the Bs->Kpi, Lb-ppi and Lb->pK decay modes and on the measurement of their branching fractions and direct CP asymmetries.

  3. First observation of radiative B⁰ → ΦK⁰γ decays and measurements of their time-dependent CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, Himansu B.; Browder, Thomas E.; Adachi, I.; Asner, David M.; Aulchenko, V.; Bakich, A. M.; Barberio, E.; Belous, K.; Bhardwaj, V.; Bhuyan, Bipul; Bondar, A.; Bozek, A.; Bracko, Marko; Brovchenko, O.; Chen, A.; Chen, P.; Cheon, B. G.; Cho, K.; Choi, Y.; Dalseno, J.; Dolezal, Z.; Drasal, Z.; Eidelman, S.; Epifanov, D.; Fast, James E.; Gaur, Vipin; Gabyshev, N.; Haba, J.; Hayasaka, K.; Hayashii, H.; Horii, Y.; Hoshi, Y.; Hou, W. S.; Hsiung, Y. B.; Hyun, H. J.; Iijima, T.; Inami, K.; Ishikawa, A.; Itoh, R.; Iwabuchi, M.; Iwasaki, Y.; Iwashita, T.; Joshi, N. J.; Julius, T.; Kang, J. H.; Kawasaki, T.; Kiesling, C.; Kim, H. J.; Kim, H. O.; Kim, J. B.; Kim, J. H.; Kim, K. T.; Kim, M. J.; Kim, S. K.; Kim, Y. J.; Kinoshita, Kay; Ko, Byeong Rok; Kobayashi, N.; Koblitz, S.; Kodys, P.; Korpar, S.; Krizan, P.; Kuhr, T.; Kumar, R.; Kumita, T.; Kuzmin, A.; Kwon, Y. J.; Lange, J. S.; Lee, M. J.; Lee, S. H.; Li, J.; Li, Y.; Libby, J.; Lim, C. L.; Liu, Z. Q.; Liventsev, Dmitri; Louvot, R.; Matvienko, D.; McOnie, S.; Miyabayashi, K.; Miyata, H.; Miyazaki, Y.; Mizuk, R.; Mohanty, G. B.; Mori, T.; Nakao, M.; Natkaniec, Z.; Ng, C.; Nishida, S.; Nishimura, Kurtis A.; Nitoh, O.; Nozaki, T.; Ohshima, T.; Okuno, S.; Olsen, Stephen L.; Onuki, Y.; Pakhlov, P.; Pakhlova, Galina; Park, C. W.; Park, H. K.; Peng, T.; Pestotnik, Rok; Petric, Marko; Piilonen, Leo E.; Prim, M.; Rohrken, M.; Ryu, S.; Sakai, K.; Sakai, Y.; Sanuki, T.; Schneider, O.; Schwanda, C.; Schwartz, A. J.; Senyo, K.; Seon, O.; Sevior, Martin E.; Shapkin, M.; Shebalin, V.; Shibata, T. A.; Shiu, Jing-Ge; Shwartz, B.; Simon, F.; Smerkol, P.; Sohn, Young-Soo; Sokolov, Anatoly; Solovyeva, Elena; Stanic, S.; Staric, M.; Sumihama, M.; Sumisawa, K.; Sumiyoshi, T.; Suzuki, S.; Tatishvili, Gocha; Teramoto, Y.; Trabelsi, K.; Uchida, M.; Uglov, T.; Unno, Yuji; Uno, S.; Ushiroda, Y.; Vahsen, Sven E.; Varner, Gary; Vinokurova, A.; Watanabe, M.; Watanabe, Y.; Williams, K. M.; Won, Eun Il; Yabsley, B. D.; Yamashita, Y.; Yuan, C. Z.; Yusa, Y.; Zhang, C. C.; Zhang, Z. P.; Zhilich, V.; Zhou, Peng; Zhulanov, V.; Zupanc, A.

    2011-10-06

    We report the first observation of the radiative decay B⁰→ ΦK⁰γ using a data sample of 772 × 10⁶ BB¯ pairs collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e⁺e⁻ collider. We observe a signal of 37 ± 8 events with a significance of 5.4 standard deviations including systematic uncertainties. The measured branching fraction is B(B⁰→ ΦK⁰γ) = (2.74±0.60±0.32)×10⁻⁶, where the uncertainties are statistical and systematic, respectively. We also report the first measurements of time-dependent CP-violation parameters: S ΦK⁰Sγ = +0.74⁺0.72 –1.05(stat)+0.10 –0.24(syst) and A ΦK⁰Sγ = +0.35 ± 0.58(stat)+0.23 –0.10(syst). Furthermore, we measure B(B⁺ → ΦK⁺γ) = (2.48 ± 0.30 ± 0.24) × 10⁻⁶, ACP = –0.03 ± 0.11 ± 0.08 and find that the signal is concentrated in the MΦK mass region near threshold.

  4. Inclusive search for the charmless radiative decay of the b-quark ( b → sγ)

    Science.gov (United States)

    Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alcaraz, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Anderson, A. L.; Andreev, V. P.; Angelescu, T.; Antonov, L.; Antreasyan, D.; Arce, P.; Arefiev, A.; Atamanchuk, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Bakken, J. A.; Ball, R. C.; Banerjee, S.; Bao, J.; Barillère, R.; Barone, L.; Baschirotto, A.; Battiston, R.; Bay, A.; Becattini, F.; Bechtluft, J.; Becker, R.; Becker, U.; Behner, F.; Behrens, J.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Bosetti, M.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brock, I. C.; Brooks, M.; Bujak, A.; Burger, J. D.; Burger, W. J.; Busenitz, J.; Buytenhuijs, A.; Cai, X. D.; Capell, M.; Caria, M.; Carlino, G.; Cartacci, A. M.; Castello, R.; Cerrada, M.; Cesaroni, F.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chen, W. Y.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Chung, S.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Contin, A.; Cotorobai, F.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; DeNotaristefani, F.; Dhina, M.; DiBitonto, D.; Diemoz, M.; Dimitrov, H. R.; Dionisi, C.; Dittmar, M.; Djambazov, L.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duinker, P.; Duran, I.; Easo, S.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Extermann, P.; Fabbretti, R.; Fabre, M.; Falciano, S.; Fan, S. J.; Fackler, O.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Finocchiaro, G.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Friebel, W.; Fukushima, M.; Gailloud, M.; Galaktionov, Yu.; Gallo, E.; Ganguli, S. N.; Garcia-Abia, P.; Gele, D.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M.; Gu, C.; Guanziroli, M.; Guo, J. K.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hangarter, K.; Hartmann, B.; Hasan, A.; Hauschildt, D.; He, C. F.; He, J. T.; Hebbeker, T.; Hebert, M.; Hervé, A.; Hilgers, K.; Hofer, H.; Hoorani, H.; Hu, G.; Hu, G. Q.; Ille, B.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jezequel, S.; Jin, B. N.; Jones, L. W.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirsch, S.; Kittel, W.; Klimentov, A.; Klöckner, R.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krastev, V. R.; Krenz, W.; Krivshich, A.; Kuijten, H.; Kumar, K. S.; Kunin, A.; Landi, G.; Lanske, D.; Lanzano, S.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, D. M.; Lee, J. S.; Lee, K. Y.; Leedom, I.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Li, C.; Li, H. T.; Li, P. J.; Liao, J. Y.; Lin, W. T.; Lin, Z. Y.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Lohmann, W.; Longo, E.; Lu, Y. S.; Lubbers, J. M.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, J. M.; Ma, W. G.; MacDermott, M.; Malik, R.; Malinin, A.; Maña, C.; Maolinbay, M.; Marchesini, P.; Marion, F.; Marin, A.; Martin, J. P.; Martinez-Laso, L.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McBride, P.; McMahon, T.; McNally, D.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; Mills, G. B.; Mir, Y.; Mirabelli, G.; Munich, J.; Möller, M.; Monteleoni, B.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nadtochy, A.; Nagy, E.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Neyer, C.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Perrier, J.; Pevsner, A.; Piccolo, D.; Pieri, M.; Piroué, P. A.; Plasil, F.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Qi, Z. D.; Qian, J. M.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Romero, L.; Rosier-Lees, S.; Rosmalen, R.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubbia, A.; Rubio, J. A.; Rykaczewski, H.; Sachwitz, M.; Salicio, J.; Salicio, J. M.; Sanders, G. S.; Santocchia, A.; Sarakinos, M. S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Schopper, H.; Schotanus, D. J.; Shotkin, S.; Schreiber, H. J.; Shukla, J.; Schulte, R.; Schulte, S.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Scott, I.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Sheer, I.; Shen, D. Z.; Shevchenko, S.; Shi, X. R.; Shumilov, E.; Shoutko, V.; Son, D.; Sopczak, A.; Spartiotis, C.; Spickermann, T.; Spillantini, P.; Starosta, R.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Strauch, K.; Stringfellow, B. C.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Terzi, G.; Ting, Samuel C. C.; Ting, S. M.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Tung, K. L.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; Van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, C.; Wang, C. R.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Warner, C.; Weber, A.; Weber, J.; Weill, R.; Wenaus, T. J.; Wenninger, J.; White, M.; Willmott, C.; Wittgenstein, F.; Wright, D.; Wu, S. X.; Wynhoff, S.; Wysłouch, B.; Xie, Y. Y.; Xu, J. G.; Xu, Z. Z.; Xue, Z. L.; Yan, D. S.; Yang, B. Z.; Yang, C. G.; Yang, G.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; Yin, Z. W.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zemp, P.; Zeng, M.; Zeng, Y.; Zhang, D. H.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.; L3 Collaboration

    1993-11-01

    We report on the search for the electromagnetic penguin decay b → sγ at √ s ≈ mz. We find no evidence for a signal and place an upper limit on the decay rate Br( b → sγ) < 1.2 × 10 -3 at 90% C.L..

  5. Rare B decays at LEP

    CERN Document Server

    Kluit, P M

    2001-01-01

    The results of the LEP experiments for rare B decays will be reviewed, covering hadronic final states, radiative and other rare decays and results for the inclusive charmless branching ratio. (8 refs).

  6. The Observation of the Weak Radiative Hyperon Decay Ξ°→Λ°π°γ at KTeV/E799, Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Huican [Univ. of Wisconsin, Madison, WI (United States)

    2005-01-01

    The large sample of Ξ° hyperons available at KTeV 799 provides an opportunity to search for the Weak Radiative Hyperon Decay Ξ° → Λ°π°γ. We present a branching fraction measurement of Ξ° → Λ°π°γ based on the E799-II experiment data-taking in 1999 at KTeV, Fermilab. We used the principal decay of Ξ° → Λ°π where Λ decays to a proton and a π- as the flux normalization mode. This is the first observation of this interesting decay mode. Four candidate events are found in the data. The branching ratio at 90% confidence level has been measured to be (1.67-0.80+1.45(stat.) ± 0.50(syst.)) x 10-5 or (1.67-0.69+1.16(stat.) ± 0.50(syst.)) x 10-5 at 68.27% confidence level.

  7. A Search for Direct CP Violation in $K^{\\pm} \\to \\pi^{\\pm} \\pi^{\\pm} \\pi^{\\mp}$ Decays

    Energy Technology Data Exchange (ETDEWEB)

    Choong, Woon Seng [Univ. of California, Berkeley, CA (United States)

    2000-01-01

    An experimental search for CP violation in $K^{\\pm} \\to \\pi^{\\pm} \\pi^{\\pm} \\pi^{\\mp}$ decays has been performed in Experiment 871 at the Fermi National Accelerator Laboratory. The experiment used an 800 GeV/c primary proton beam impinging on copper targets to produce charged Kaons which were then collimated through a curved channel in a magnetic field. The three pions from the Kaon decays were tracked in the spectrometer with four high-rate multiwire proportional chambers upstream of an analysis magnet and four more downstream. The data was collected between April 1997 and September 1997, resulting in 43.3 billion positive and 18.8 billion negative Kaon triggers. Based on 41.8 million $\\tau^+$ decays and 12.4 million $\\tau^-$ decays of charged Kaon, the linear slope parameter $g$ describing the energy spectrum of the odd pion in the expansion of the squared matrix element was estimated using a Hybrid Monte Carlo method. This is the largest sample of $\\tau$ decays of charged Kaons ever analyzed, over an order of magnitude larger than the previous analysis. The asymmetry in the linear slope $g$ was found to be $\\frac{\\Delta g}{2g_{PDG}}$ = [2.2 $\\pm$ 1.5(stat) $\\pm$ 3.7(syst)] x $10^{-3}$ This result is consistent with no CP violation in $K^{\\pm} \\to \\pi^{\\pm} \\pi^{\\pm} \\pi^{\\mp}$ decays.

  8. The Rare Decays $B^0_{(s)}\\to\\mu^+\\mu^-$ and $Z$ Boson Production at LHCb and Radiation Damage in its Silicon Tracker

    CERN Document Server

    Elsasser, Christian; Müller, Katharina; Steinkamp, Olaf; Baudis, Laura

    The LHCb experiment at the Large Hadron Collider is dedicated to the study of physics involving beauty and charm quarks. Its detector $-$ designed as a single-arm forward spectrometer $-$ uses tracking stations upstream and downstream of a dipole magnet to measure the trajectories and the momenta of charged particles. Parts of this tracking system are built from silicon micro-strip detectors. This thesis describes the monitoring of the radiation damage in these detectors using leakage current measurements and so-called Charge Collection Efficiency scans performed in regular intervals during data taking. The results of this monitoring during the first LHC data taking period from 2010 to 2013 are presented and predictions for the future evolution of the detector ageing are discussed. A main goal of LHCb is the measurement of rare decays. As these decays are heavily suppressed in the Standard Model, their properties, for example the branching fraction, angular distributions or $CP$ asymmetries, can be significan...

  9. Search for X-ray induced decay of the 31-yr isomer of 178Hf using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I; Banar, J C; Becker, J A; Bredeweg, T A; Cooper, J R; Gemmell, D S; Kraemer, A; Mashayekhi, A; McNabb, D P; Miller, G G; Moore, E F; Palmer, P; Pangault, L N; Rundberg, R S; Schiffer, J P; Shastri, S D; Wang, T F; Wilhelmy, J B

    2004-09-13

    Isomeric {sup 178}Hf (t{sub 1/2} = 31 yr, E{sub x} = 2.446 MeV, J{sup {pi}} = 16{sup +}) was bombarded by a white beam of x-rays from the Advanced Photon Source at Argonne National Laboratory. A search was made for x-ray induced decay of the isomer by detecting prompt and delayed {gamma} rays associated with the decay. No induced decay was observed. Upper limits for such a process for x-ray energies between 7-100 keV were set. The limits between 7 and 30 keV are below {approx} 3 x 10{sup -27} cm{sup 2}-keV for induced decay that bypasses the 4-s isomer and {approx} 5 x 10{sup -27} cm{sup 2}-keV for induced decay that is delayed through this isomer, orders of magnitude below values at which induced decay was reported previously. These limits are consistent with what is known about the properties of atomic nuclei.

  10. Studies of the Strange Sea-Quarks Spin with Kaons

    Science.gov (United States)

    Benmokhtar, Fatiha; Voloshin, Andrew; Goodwill, Justin; Lendacky, Andrew

    2017-01-01

    It is well known that quarks and gluons give the substructure to the nucleons. and understanding of the spin structure of the nucleon in terms of quarks and gluons has been the goal of intense investigations during the last decades. The determination of strangeness is challenging and the only way of determining the strange distribution accurately from data is to improve the semi-inclusive information. This talk is focused on the determination of the strange sea contribution to the nucleon spin through the pseudo-scalar method using semi-inclusive Kaon detection technique with CLAS12 at Jefferson Lab. A Ring Imaging CHerenkov (RICH) detector is under construction and will be used for pion-kaon-proton separation. National Science Foundation #1615067.

  11. Valence-quark distribution functions in the kaon and pion

    CERN Document Server

    Chen, Chen; Roberts, Craig D; Wan, Shaolong; Zong, Hong-Shi

    2016-01-01

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed-quarks carry all a meson's momentum at a characteristic hadronic scale and vanishing as $(1-x)^2$ when Bjorken-$x\\to 1$. Comparing such distributions within the pion and kaon, it is apparent that the size of SU(3)-flavour symmetry breaking in meson parton distribution functions is modulated by the flavour dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulae may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea-quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison...

  12. Radiative corrections of O(α) to B{sup -} → V{sup 0}l{sup -} anti ν{sub l} decays

    Energy Technology Data Exchange (ETDEWEB)

    Tostado, S.L. [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Departamento de Fisica, Mexico, D.F. (Mexico); Castro, G.L. [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Departamento de Fisica, Mexico, D.F. (Mexico); CSIC- Universitat de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain)

    2016-09-15

    The O(α) electromagnetic radiative corrections to the B{sup -} → V{sup 0}l{sup -} anti ν{sub l} (V is a vector meson and l a charged lepton) decay rates are evaluated using the cutoff method to regularize virtual corrections and incorporating intermediate resonance states in the real-photon amplitude to extend the region of validity of the soft-photon approximation. The electromagnetic and weak form factors of hadrons are assumed to vary smoothly over the energies of virtual and real photons under consideration. The cutoff dependence of radiative corrections upon the scale Λ that separates the long- and short-distance regimes is found to be mild and is considered as an uncertainty of the calculation. Owing to partial cancellations of electromagnetic corrections evaluated over the three- and four-body regions of phase space, the photon-inclusive corrected rates are found to be dominated by the short-distance contribution. These corrections will be relevant for a precise determination of the b quark mixing angles by testing isospin symmetry when measurements of semileptonic rates of charged and neutral B mesons at the few percent level become available. For completeness, we also provide numerical values of radiative corrections in the three-body region of the Dalitz plot distributions of these decays. (orig.)

  13. Kaon Photoproduction Near Threshold in Six Isospin Channels Revisited

    Science.gov (United States)

    Mart, T.

    2016-08-01

    In this talk I review the progress achieved in the investigation of kaon photoproduction on the nucleon near the production threshold. This investigation has been performed by using the so-called isobar model, which makes use of Feynman diagrams for the background terms and the Breit-Wigner multipoles for the resonance terms. The future prospect as well as application of this model in the hadronic sector are also briefly discussed.

  14. Light-front model of the kaon electromagnetic current

    CERN Document Server

    Pacheco-Bicudo-Cabral de Melo, J; Frederico, T; Tomio, Lauro

    2003-01-01

    The electromagnetic form factor is extracted from both components of the electromagnetic current: J(plus) and J(minus) with a pseudo-scalar coupling of the quarks to the kaon. In the case of J(plus) there is no pair term contribution in the Drell-Yan frame. However, J(minus) component of the electromagnetic current the pair term contribution is different from zero and is necessary include it to preserve the rotational symmetry of the current.

  15. Surface Tension between Kaon Condensate and Normal Nuclear Matter Phase

    OpenAIRE

    Christiansen, Michael B.; Glendenning, Norman K.; Schaffner-Bielich, Jurgen

    2000-01-01

    We calculate for the first time the surface tension and curvature coefficient of a first order phase transition between two possible phases of cold nuclear matter, a normal nuclear matter phase in equilibrium with a kaon condensed phase, at densities a few times the saturation density. We find the surface tension is proportional to the difference in energy density between the two phases squared. Furthermore, we show the consequences for the geometrical structures of the mixed phase region in ...

  16. Probing flavor and CP in decays of beauty and charm

    Energy Technology Data Exchange (ETDEWEB)

    Schacht, Stefan

    2013-07-10

    In order to probe for new physics beyond the Standard Model of particle physics, we explore decays of beauty and charm mesons. In the b sector we find ourselves in the realm of precision physics so that we can improve significantly the bounds on supersymmetric flavor violation from new theoretical and experimental progress in anti B → anti K{sup (*)}l{sup +}l{sup -}. From these bounds we derive several phenomenological implications, as bounds on Radiative Flavor Violation models that are partly even sharper than the ones from Kaon physics. In order to improve the bounds on new physics models from anti B → anti K{sup (*)}l{sup +}l{sup -} even more in the future, we extract subsequently anti B → anti K{sup *} form factor ratios from data at high invariant lepton pair masses. These are the current bottleneck for the advancement in precision. In the charm sector unexpectedly large CP violation was measured recently. Currently, the experimental situation is unsettled. We work here on the main problem that one cannot reliably calculate the hadronic part from first principles, i.e., cannot exclude possible enhancements from this source. We perform for the first time a comprehensive SU(3){sub F} analysis of D → P{sub 8}P{sub 8} decays including linear breaking in full generality. We find the SU(3){sub F} expansion to be indeed working. Furthermore, the fit shows a large triplet matrix element enhancement that cannot be excluded for sure without having a dynamical theory at hand. We show as a proof of principle that with significantly improved data we could disentangle the triplet model including the Standard Model from other new physics models. Using reasonable theoretical input from QCD factorization we can eliminate some of the many degrees of freedom of the pure SU(3){sub F} analysis. This can sharpen partially the correlation between D-decay CP asymmetries and branching ratios.

  17. Bose-Einstein Correlations of Charged and Neutral Kaons in Deep Inelastic Scattering at HERA

    CERN Document Server

    Chekanov, S; Magill, S; Musgrave, B; Nicholass, D; Repond, J; Yoshida, R; Mattingly, M C K; Jechow, M; Pavel, N; Yagues-Molina, A G; Antonelli, S; Antonioli, P; Bari, G; Basile, M; Bellagamba, L; Bindi, M; Boscherini, D; Bruni, A; Bruni, G; Cifarelli, L; Cindolo, F; Contin, A; Corradi, M; De Pasquale, S; Iacobucci, G; Margotti, A; Nania, R; Polini, A; Sartorelli, G; Zichichi, A; Bartsch, D; Brock, I; Goers, S; Hartmann, H; Hilger, E; Jakob, H P; Jüngst, M; Kind, O M; Nuncio-Quiroz, A E; Paul, E; Renner, R; Samson, U; Schonberg, V; Shehzadi, R; Wlasenko, M; Brook, N H; Heath, G P; Morris, J D; Namsoo, T; Capua, M; Fazio, S; Mastroberardino, A; Schioppa, M; Susinno, G; Tassi, E; Kim, J Y; Ma, K J; Ibrahim, Z A; Kamaluddin, B; Wan-Abdullah, W A T; Ning, Y; Ren, Z; Sciulli, F; Chwastowski, J; Eskreys, A; Figiel, J; Galas, A; Gil, M; Olkiewicz, K; Stopa, P; Zawiejski, L; Adamczyk, L; Bold, T; Grabowska-Bold, I; Kisielewska, D; Lukasik, J; Przybycien, M; Suszycki, L; Kotanski, A; Slominski, W; Adler, V; Behrens, U; Bloch, I; Blohm, C; Bonato, A; Borras, K; Ciesielski, R; Coppola, N; Dossanov, A; Drugakov, V; Fourletova, J; Geiser, A; Gladkov, D; Göttlicher, P; Grebenyuk, J; Gregor, I; Haas, T; Hain, W; Horn, C; Huttmann, A; Kahle, B; Katkov, I I; Klein, U; Kötz, U; Kowalski, H; Lobodzinska, E; Löhr, B; Mankel, R; Melzer-Pellmann, I A; Miglioranzi, S; Montanari, A; Notz, D; Rinaldi, L; Roloff, P; Rubinsky, I; Santamarta, R; Schneekloth, U; Spiridonov, A; Stadie, H; Szuba, D; Szuba, J; Theedt, T; Wolf, G; Wrona, K; Youngman, C; Zeuner, W; Lohmann, W; Schlenstedt, S; Barbagli, G; Gallo, E; Pelfer, P G; Bamberger, A; Dobur, D; Karstens, F; Vlasov, N N; Bussey, P J; Doyle, A T; Dunne, W; Ferrando, J; Forrest, M; Saxon, D H; Skillicorn, I O; Gialas, I; Papageorgiu, K; Gosau, T; Holm, U; Klanner, R; Lohrmann, E; Salehi, H; Schleper, P; Schörner-Sadenius, T; Sztuk, J; Wichmann, K; Wick, K; Foudas, C; Fry, C; Long, K R; Tapper, A D; Kataoka, M; Matsumoto, T; Nagano, K; Tokushuku, K; Yamada, S; Yamazaki, Y; Barakbaev, A N; Boos, E G; Pokrovskiy, N S; Zhautykov, B O; Aushev, V; Son, D; De Favereau, J; Piotrzkowski, K; Barreiro, F; Glasman, C; Jiménez, M; Labarga, L; Del Peso, J; Ron, E; Soares, M; Terron, J; Zambrana, M; Corriveau, F; Liu, C; Walsh, R; Zhou, C; Tsurugai, T; Antonov, A; Dolgoshein, B A; Sosnovtsev, V; Stifutkin, A; Suchkov, S; Dementiev, R K; Ermolov, P F; Gladilin, L K; Khein, L A; Korzhavina, I A; Kuzmin, V A; Levchenko, B B; Lukina, O Yu; Proskuryakov, A S; Shcheglova, L M; Zotkin, D S; Zotkin, S A; Abt, I; Büttner, C; Caldwell, A; Kollar, D; Schmidke, W B; Sutiak, J; Grigorescu, G; Keramidas, A; Koffeman, E; Kooijman, P; Pellegrino, A; Tiecke, H; Vázquez, M; Wiggers, L; Brümmer, N; Bylsma, B; Durkin, L S; Lee, A; Ling, T Y; Allfrey, P D; Bell, M A; Cooper-Sarkar, A M; Cottrell, A; Devenish, R C E; Foster, B; Korcsak-Gorzo, K; Patel, S; Roberfroid, V; Robertson, A; Straub, P B; Uribe-Estrada, C; Walczak, R; Bellan, P; Bertolin, A; Brugnera, R; Carlin, R; Dal Corso, F; Dusini, S; Garfagnini, A; Limentani, S; Longhin, A; Stanco, L; Turcato, M; Oh, B Y; Raval, A; Ukleja, J; Whitmore, J J; Iga, Y; D'Agostini, G; Marini, G; Nigro, A; Cole, J E; Hart, J C; Abramowicz, H; Gabareen, A; Ingbir, R; Kananov, S; Levy, A; Kuze, M; Maeda, J; Hori, R; Kagawa, S; Okazaki, N; Shimizu, S; Tawara, T; Hamatsu, R; Kaji, H; Kitamura, S; Ota, O; Ri, Y D; Ferrero, M I; Monaco, V; Sacchi, R; Solano, A; Arneodo, M; Ruspa, M; Fourletov, S; Martin, J F; Boutle, S K; Butterworth, J M; Gwenlan, C; Jones, T W; Loizides, J H; Sutton, M R; Wing, M; Brzozowska, B; Ciborowski, J; Grzelak, G; Kulinski, P; Luzniak, P; Malka, J; Nowak, R J; Pawlak, J M; Tymieniecka, T; Ukleja, A; Zarnecki, A F; Adamus, M; Plucinsky, P P; Eisenberg, Y; Giller, I; Hochman, D; Karshon, U; Rosin, M; Brownson, E; Danielson, T; Everett, A; Kcira, D; Reeder, D D; Ryan, P; Savin, A A; Smith, W H; Wolfe, H; Bhadra, S; Catterall, C D; Cui, Y; Hartner, G; Menary, S; Noor, U; Standage, J; Whyte, J

    2007-01-01

    Bose-Einstein correlations of charged and neutral kaons have been measured in e+-p deep inelastic scattering with an integrated luminosity of 121 pb-1 using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, Q_12=sqrt{-(p_1-p_2)^2}, assuming a Gaussian shape for the particle source. The values of the radius of the production volume, r, and of the correlation strength, lambda, were obtained for both neutral and charged kaons. The radii for charged and neutral kaons are similar and are consistent with those obtained at LEP.

  18. Measurement of the charged kaon mass with the MIPP RICH

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Nicholas J. [Indiana Univ., Bloomington, IN (United States)

    2008-08-01

    The currently accepted value of the charged kaon mass is 493.677 ± 0.013 MeV (26 ppm). It is a weighted average of six measurements, most of which use kaonic atom X-ray energy techniques. The two most recent and precise results dominate the average but differ by 122 ppm. Inconsistency in the data set needs to be resolved, preferably using independent techniques. One possibility uses the Cherenkov effect. A measurement of the charged kaon mass using this technique is presented. The data was taken with the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory using a tagged beam of protons, kaons, and pions ranging in momentum from 37 GeV/c to 63 GeV/c. The measured value is 491.3 ± 1.7 MeV. This is within 1.4σ of the current value. An improvement in precision by a factor of 35 would make this technique competitive for resolving the ambiguity in the X-ray data.

  19. Charged Kaon Mass Measurement using the Cherenkov Effect

    Energy Technology Data Exchange (ETDEWEB)

    Graf, N.; /Indiana U.; Lebedev, A.; /Harvard U., Phys. Dept.; Abrams, R.J.; /Michigan U.; Akgun, U.; Aydin, G.; /Iowa U.; Baker, W.; /Fermilab; Barnes, P.D., Jr.; /LLNL, Livermore; Bergfeld, T.; /South Carolina U.; Beverly, L.; /Fermilab; Bujak, A.; /Purdue U.; Carey, D.; /Fermilab /Virginia U. /Iowa U.

    2009-09-01

    The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 ppm and 22 ppm yet differ from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 GeV/c to +63 GeV/c. The measured value is 491.3 {+-} 1.7 MeV/c{sup 2}, which is within 1.4{sigma} of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.

  20. $B^{(*)}\\bar B^{(*)}$ intermediate state contribution to $\\Upsilon(4S,5S)\\to \\eta_b+\\gamma$ radiative decay

    OpenAIRE

    2010-01-01

    In this work, we investigate the re-scattering effects in the radiative decay $\\Upsilon(5S)\\to\\eta_b+\\gamma$, which were suggested to be crucially important for understanding the anomalous largeness of the branching ratios $B(\\Upsilon(5S)\\to \\Upsilon(1S)+\\pi\\pi)$ and $B(\\Upsilon(5S)\\to \\Upsilon(1S)+\\eta)$. Our calculations show that the re-scattering effects may enhance $\\Gamma(\\Upsilon(10860)\\to \\eta_b+\\gamma)$ by four orders, but the tetraquark structure does not. Recently the BaBar and CLE...

  1. RARE K DECAYS: RESULTS AND PROSPECTS.

    Energy Technology Data Exchange (ETDEWEB)

    LITTENBERG,L.

    2001-09-10

    In recent years the study of the rare decays of kaons has had three primary motivations. The first is the search for physics beyond the Standard Model (BSM). Virtually all attempts to redress the theoretical shortcomings of the Standard Model (SM) predict some degree of lepton flavor violation (LFV). Decays such as K{sub L} {yields} {mu}{sup {+-}}e{sup {-+}} have very good experimental signatures and can consequently be pursued to remarkable sensitivities. These sensitivities correspond to extremely high energy scales in models where the only suppression is that of the mass of the exchanged field. There are also theories that predict new particles created in kaon decay or the violation of symmetries other than lepton flavor. The second is the potential of decays that are allowed but that are extremely suppressed in the SM. In several of these, the leading component is a G.I.M.-suppressed one-loop process that is quite sensitive to fundamental SM parameters such as V{sub td}. These decays are also potentially very sensitive to BSM physics. Finally there are a number of long-distance-dominated decays which can test theoretical techniques such as chiral Lagrangians that purport to explain the low-energy behavior of QCD. Knowledge of some of these decays is also needed to extract more fundamental information from certain of the one-loop processes. This field is quite active as indicated by Table 1 that lists the decays for which results have been forthcoming in the last couple of years as well as those that are under analysis. Thus in a short review such as this, one must be quite selective.

  2. Measurement of pion, kaon and proton production in proton-proton collisions at [Formula: see text] TeV.

    Science.gov (United States)

    Adam, J; Adamová, D; Aggarwal, M M; Rinella, G Aglieri; Agnello, M; Agrawal, N; Ahammed, Z; Ahmed, I; Ahn, S U; Aimo, I; Aiola, S; Ajaz, M; Akindinov, A; Alam, S N; Aleksandrov, D; Alessandro, B; Alexandre, D; Molina, R Alfaro; Alici, A; Alkin, A; Alme, J; Alt, T; Altinpinar, S; Altsybeev, I; Prado, C Alves Garcia; Andrei, C; Andronic, A; Anguelov, V; Anielski, J; Antičić, T; Antinori, F; Antonioli, P; Aphecetche, L; Appelshäuser, H; Arcelli, S; Armesto, N; Arnaldi, R; Aronsson, T; Arsene, I C; Arslandok, M; Augustinus, A; Averbeck, R; Azmi, M D; Bach, M; Badalà, A; Baek, Y W; Bagnasco, S; Bailhache, R; Bala, R; Baldisseri, A; Ball, M; Pedrosa, F Baltasar Dos Santos; Baral, R C; Barbano, A M; Barbera, R; Barile, F; Barnaföldi, G G; Barnby, L S; Barret, V; Bartalini, P; Bartke, J; Bartsch, E; Basile, M; Bastid, N; Basu, S; Bathen, B; Batigne, G; Camejo, A Batista; Batyunya, B; Batzing, P C; Bearden, I G; Beck, H; Bedda, C; Behera, N K; Belikov, I; Bellini, F; Martinez, H Bello; Bellwied, R; Belmont, R; Belmont-Moreno, E; Belyaev, V; Bencedi, G; Beole, S; Berceanu, I; Bercuci, A; Berdnikov, Y; Berenyi, D; Bertens, R A; Berzano, D; Betev, L; Bhasin, A; Bhat, I R; Bhati, A K; Bhattacharjee, B; Bhom, J; Bianchi, L; Bianchi, N; Bianchin, C; Bielčík, J; Bielčíková, J; Bilandzic, A; Biswas, S; Bjelogrlic, S; Blanco, F; Blau, D; Blume, C; Bock, F; Bogdanov, A; Bøggild, H; Boldizsár, L; Bombara, M; Book, J; Borel, H; Borissov, A; Borri, M; Bossú, F; Botje, M; Botta, E; Böttger, S; Braun-Munzinger, P; Bregant, M; Breitner, T; Broker, T A; Browning, T A; Broz, M; Brucken, E J; Bruna, E; Bruno, G E; Budnikov, D; Buesching, H; Bufalino, S; Buncic, P; Busch, O; Buthelezi, Z; Buxton, J T; Caffarri, D; Cai, X; Caines, H; Diaz, L Calero; Caliva, A; Villar, E Calvo; Camerini, P; Carena, F; Carena, W; Castellanos, J Castillo; Castro, A J; Casula, E A R; Cavicchioli, C; Sanchez, C Ceballos; Cepila, J; Cerello, P; Chang, B; Chapeland, S; Chartier, M; Charvet, J L; Chattopadhyay, S; Chattopadhyay, S; Chelnokov, V; Cherney, M; Cheshkov, C; Cheynis, B; Barroso, V Chibante; Chinellato, D D; Chochula, P; Choi, K; Chojnacki, M; Choudhury, S; Christakoglou, P; Christensen, C H; Christiansen, P; Chujo, T; Chung, S U; Cicalo, C; Cifarelli, L; Cindolo, F; Cleymans, J; Colamaria, F; Colella, D; Collu, A; Colocci, M; Balbastre, G Conesa; Valle, Z Conesa Del; Connors, M E; Contreras, J G; Cormier, T M; Morales, Y Corrales; Maldonado, I Cortés; Cortese, P; Cosentino, M R; Costa, F; Crochet, P; Albino, R Cruz; Cuautle, E; Cunqueiro, L; Dahms, T; Dainese, A; Danu, A; Das, D; Das, I; Das, S; Dash, A; Dash, S; De, S; Caro, A De; Cataldo, G de; Cuveland, J de; Falco, A De; Gruttola, D De; Marco, N De; Pasquale, S De; Deisting, A; Deloff, A; Dénes, E; D'Erasmo, G; Bari, D Di; Mauro, A Di; Nezza, P Di; Corchero, M A Diaz; Dietel, T; Dillenseger, P; Divià, R; Djuvsland, Ø; Dobrin, A; Dobrowolski, T; Gimenez, D Domenicis; Dönigus, B; Dordic, O; Dubey, A K; Dubla, A; Ducroux, L; Dupieux, P; Ehlers, R J; 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    The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

  3. Measurement of pion, kaon and proton production in proton-proton collisions at $\\sqrt{s}$ = 7 TeV

    CERN Document Server

    Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahmed, Ijaz; Ahn, Sang Un; Aimo, Ilaria; Aiola, Salvatore; Ajaz, Muhammad; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Armesto Perez, Nestor; Arnaldi, Roberta; Aronsson, Tomas; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Ball, Markus; Baltasar Dos Santos Pedrosa, Fernando; Baral, Rama Chandra; 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De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; D'Erasmo, Ginevra; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Engel, Heiko; Erazmus, Barbara Ewa; Erhardt, Filip; Eschweiler, Dominic; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Eyyubova, Gyulnara; Fabbietti, Laura; Fabris, Daniela; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Felea, Daniel; Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Gao, Chaosong; Garabatos Cuadrado, Jose; Garcia-Solis, Edmundo Javier; Gargiulo, Corrado; Gasik, Piotr Jan; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez Ramirez, Andres; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Grelli, Alessandro; Grigoras, Alina Gabriela; 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Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacobs, Peter Martin; Jahnke, Cristiane; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jung, Hyungtaik; Jusko, Anton; Kadyshevskiy, Vladimir; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Kamal; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Do Won; Kim, Dong Jo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Mimae; Kim, Minwoo; Kim, Se Yong; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Kiss, Gabor; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-Boesing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobayashi, Taiyo; Kobdaj, Chinorat; Kofarago, Monika; Kohler, Markus Konrad; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kouzinopoulos, Charalampos; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Kox, Serge; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kravcakova, Adela; Krelina, Michal; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kucheryaev, Yury; Kugathasan, Thanushan; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kulakov, Igor; Kumar, Jitendra; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kushpil, Svetlana; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Lagana Fernandes, Caio; Lakomov, Igor; Langoy, Rune; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Lattuca, Alessandra; Laudi, Elisa; Lea, Ramona; Leardini, Lucia; Lee, Graham Richard; Lee, Seongjoo; Legrand, Iosif; Lehnert, Joerg Walter; Lemmon, Roy Crawford; Lenti, Vito; Leogrande, Emilia; Leon Monzon, Ildefonso; Leoncino, Marco; Levai, Peter; Li, Shuang; Li, Xiaomei; Lien, Jorgen Andre; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Ljunggren, Hans Martin; Lodato, Davide Francesco; Lonne, Per-Ivar; Loggins, Vera Renee; Loginov, Vitaly; Loizides, Constantinos; Lokesh, Kumar; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Lu, Xianguo; Luettig, Philipp Johannes; Lunardon, Marcello; Luparello, Grazia; Maevskaya, Alla; Mager, Magnus; Mahajan, Sanjay; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Liudmila; Mal'Kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manceau, Loic Henri Antoine; Manko, Vladislav; Manso, Franck; Manzari, Vito; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martin, Nicole Alice; Martin Blanco, Javier; Martinengo, Paolo; Martinez Hernandez, Mario Ivan; Martinez-Garcia, Gines; Martinez Pedreira, Miguel; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Mastroserio, Annalisa; Masui, Hiroshi; Matyja, Adam Tomasz; Mayer, Christoph; Mazer, Joel Anthony; Mazzoni, Alessandra Maria; Mcdonald, Daniel; Meddi, Franco; Menchaca-Rocha, Arturo Alejandro; Meninno, Elisa; Mercado-Perez, Jorge; Meres, Michal; Miake, Yasuo; Mieskolainen, Matti Mikael; Mikhaylov, Konstantin; Milano, Leonardo; Milosevic, Jovan; Minervini, Lazzaro Manlio; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Montes Prado, Esther; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Muller, Hans; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Murray, Sean; Musa, Luciano; Musinsky, Jan; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Naru, Muhammad Umair; Nattrass, Christine; Nayak, Kishora; Nayak, Tapan Kumar; Nazarenko, Sergey; Nedosekin, Alexander; Nellen, Lukas; Ng, Fabian; Nicassio, Maria; Niculescu, Mihai; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Ohlson, Alice Elisabeth; Okatan, Ali; Okubo, Tsubasa; Olah, Laszlo; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Ozdemir, Mahmut; Pachmayer, Yvonne Chiara; Pagano, Paola; Paic, Guy; Pajares Vales, Carlos; Pal, Susanta Kumar; Pan, Jinjin; Pant, Divyash; Papikyan, Vardanush; Pappalardo, Giuseppe; Pareek, Pooja; Park, Woojin; Parmar, Sonia; Passfeld, Annika; Paticchio, Vincenzo; Paul, Biswarup; Pawlak, Tomasz Jan; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitry Yurevich; Perez Lara, Carlos Eugenio; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrov, Viacheslav; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Porteboeuf, Sarah Julie; Porter, R Jefferson; Pospisil, Jan; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Punin, Valery; Putschke, Jorn Henning; Qvigstad, Henrik; Rachevski, Alexandre; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Razazi, Vahedeh; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reed, Rosi Jan; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reicher, Martijn; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riabov, Viktor; Ricci, Renato Angelo; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-Lucian; Rivetti, Angelo; Rocco, Elena; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roeed, Ketil; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Romita, Rosa; Ronchetti, Federico; Ronflette, Lucile; Rosnet, Philippe; Rossi, Andrea; Roukoutakis, Filimon; Roy, Ankhi; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Sadovskiy, Sergey; Safarik, Karel; Sahlmuller, Baldo; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Salgado Lopez, Carlos Alberto; Salzwedel, Jai Samuel Nielsen; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sanchez Castro, Xitzel; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Santagati, Gianluca; Sarkar, Debojit; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schuchmann, Simone; Schukraft, Jurgen; Schulc, Martin; Schuster, Tim Robin; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Rebecca Michelle; Seeder, Karin Soraya; Seger, Janet Elizabeth; Sekiguchi, Yuko; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Seo, Jeewon; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shangaraev, Artem; Sharma, Ankita; Sharma, Natasha; Shigaki, Kenta; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, Catherine Micaela; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Soegaard, Carsten; Soltz, Ron Ariel; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Steinpreis, Matthew Donald; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Sultanov, Rishat; Sumbera, Michal; Symons, Timothy; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Takahashi, Jun; Tanaka, Naoto; Tangaro, Marco-Antonio; Tapia Takaki, Daniel Jesus; Tarantola Peloni, Attilio; Tariq, Mohammad; Tarzila, Madalina-Gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terasaki, Kohei; Terrevoli, Cristina; Teyssier, Boris; Thaeder, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony Robert; Toia, Alberica; Trogolo, Stefano; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; 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Wang, Hongkai; Wang, Mengliang; Wang, Yifei; Watanabe, Daisuke; Weber, Michael; Weber, Steffen Georg; Wessels, Johannes Peter; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yaldo, Chris G; Yamaguchi, Yorito; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yasnopolskiy, Stanislav; Yin, Zhongbao; Yokohama, Hiroki; Yoo, In-Kwon; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zhu, Xiangrong; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2015-05-27

    The measurement of primary $\\pi^{\\pm}$, K$^{\\pm}$, p and $\\overline{p}$ production at mid-rapidity ($|y| <$ 0.5) in proton-proton collisions at $\\sqrt{s} = 7$ TeV performed with ALICE (A Large Ion Collider Experiment) at the Large Hadron Collider (LHC) is reported. Particle identification is performed using the specific ionization energy loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/$c$ for pions, from 0.2 up to 6 GeV/$c$ for kaons and from 0.3 up to 6 GeV/$c$ for protons. The measured spectra and particle ratios are compared with QCD-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

  4. Limits on the radiative decay of sterile neutrino dark matter from the unresolved cosmic and soft x-ray backgrounds

    Science.gov (United States)

    Abazajian, Kevork N.; Markevitch, Maxim; Koushiappas, Savvas M.; Hickox, Ryan C.

    2007-03-01

    We present upper limits on line emission in the Cosmic X-ray background (CXB) that would be produced by decay of sterile neutrino dark matter. We employ the spectra of the unresolved component of the CXB in the Chandra Deep Fields North and South obtained with the Chandra CCD detector in the E=0.8 9keV band. The expected decay flux comes from the dark matter on the lines of sight through the Milky Way galactic halo. Our constraints on the sterile neutrino decay rate are sensitive to the modeling of the Milky Way halo. The highest halo mass estimates provide a limit on the sterile neutrino mass of msrocket-borne calorimeter by McCammon and collaborators.

  5. Search for the Radiative Penguin Decays B+ -> rho+ gamma, B0 -> rho0 gamma, and B0 -> omega gamma

    CERN Document Server

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Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Lavin, D; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Biasini, M; Covarelli, R; Pioppi, M; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, Erwin; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Claus, R; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Sobie, R J; Band, H R; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2004-01-01

    A search for the decays B --> rho(770) gamma and B0 --> omega(782)gamma is performed on a sample of 211 million Y(4S)->BBbar events collected by the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. No evidence for the decays is seen. We set the following limits on the individual branching fractions BF(B --> rho+ gamma) rho0 gamma) omega gamma) (rho/omega) gamma]<1.2 x 10^-6 and constrain V_td/V_ts< 0.19 at the 90% C.L.

  6. The effect of atomic spontaneous decay on the dynamics of the negativity of the Wigner function of radiation

    Institute of Scientific and Technical Information of China (English)

    Abdel-Baset A. Mohamedt

    2011-01-01

    The exact solution of the master equation for the case of a high-Q cavity with atomic decay is found. We use the negativity of the Wigner function (WF) as an indicator of nonclassicality. It is found that the negative values of the field WF are very sensitive to any change in the damping parameter. The atomic spontaneous decay leads to the simultaneous disappearance of both entanglement and nonclassicality of quantum states. Moreover,the purity of the field states is completely lost.

  7. Observation of the Decay Xi(-)(b) -> pK(-)K(-)

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M. H.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A. Jr; Amato, S.; Amerio, S.; Amhis, Y.; BEACH, LA; Anderlini, L.; Andreassi, G.; Andreotti, M.; Andrews, J.E.; Appleby, R.B.; Archilli, F.; d'Argent, P.; Romeu, J. Arnau; Artamonov, AY; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Babuschkin, I.; Bachmann, S; Back, Jaap Willem; Badalov, A.; Baesso, C.; Baker, S; Balagura, V.; Baldini, W.; Barlow, R.J.; Barschel, C.; Barsuk, S.; Barter, W.; Baszczyk, M.; Batozskaya, V.; Batsukh, B.; Battista, V.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Castano-Betancourt, Martha; Betti, F.; Bettler, M.O.; van Beuzekom, MG; Bezshyiko, Ia; Bifani, S.; Billoir, P.; Bird, T.; Birnkraut, A.; Bitadze, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Boettcher, Thomas; Bondar, A.; Bondar, N.; Bonivento, W.; Bordyuzhin, I.; Borgheresi, A.; Borghi, S.; Borisyak, M.; Borsato, M.; Bossu, F.; Boubdir, M.; Bowcock, T. J. V.; Bowen, D.E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Buchanan, E.; Burr, C.; Bursche, A.; Buytaert, R. J.; Cadeddu, S.; Calabrese, J. R.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Campana, P.; Perez, D. H. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cavallero, G.; Cenci, R.; Chamont, D.; Charles, M; Charpentier, Ph.; Chatzikonstantinidis, G.; Chefdeville, M.; Cheung, T.F.S.; Chobanova, V.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; COOK, AM; Coombs, Geoffrey W.; Coquereau, S.; Corti, G.; Corvo, M.; Sobral, C. M. Costa; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Da Cunha Marinho, F.; Dall'Occo, E.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; Miranda, J. M.; De Paula, L.; De Serio, M.; De Simone, Paolo; Dean, C. -T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Demmer, M.; Dendek, A.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Dordei, F.; Dorigo, M.; Dosil Suarez, A.; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dungs, K.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Deleage, N.; Easo, S.; Ebert, Martin A.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; Ely, SIdi Ould; Esen, S.; Evans, Helen M.; Evans, T.; Falabella, A.; Farley, N.; Farry, S.; Fay, R. F.; Fazzini, D.; FERGUSON, D; Fernandez Prieto, A.; Ferrari, F; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fini, R. A.; Fiore, M; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fleuret, F.; Fohl, K; Fontana, M.; Fontanelli, F.; Forshaw, D. C.; Forty, R.; Lima, V. Franco; Frei, C.; Funk, Walter D.; Furfaro, E.; Farber, CR; Torreira, A. Gallas; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Garcia Martin, L. M.; Garcia Pardinas, J.; Tico, J. Garra; Garrido, L.; Garsed, P. J.; Gascon, D.; Gaspar, C; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E. G; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Giani', S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gizdov, K.; Gligorov, V. V.; Golubkov, D.; Golutvin, A.; Gorelov, I. V.; Gotti, C.; Graciani Diaz, R.; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Griffith, P.; Grillo, L.; Cazon, B. R. Gruberg; Gruenberg, O.; Gushchin, EM; Guz, Yu.; Gys, T.; Gobel, C.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, D.B.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, Christine J.; Hatch, M.; He, J. J.; Head, T.; Heister, J. A.; Hennessy, K.; Henrard, P.; Henry, Lee; Van Herwijnen, E.; Hess, M.; Hicheur, A.; HILL, D; Hombach, C.; Hopchev, H.; Hulsbergen, W.; Humair, T.; Hushchyn, M.; Hutchcroft, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jalocha, J.; Jans, E.; Jawahery, A.; Jiang, Fuman; John, Jestinah M. Mahachie; Johnson, D; Jones, Jonathan C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Karacson, M.; Kariuki, J. M.; Karodia, S.; Kecke, M.; Kelsey, M.; Kenzie, M.; Ketel, T. J.; Khairullin, E.; Khanji, B.; Khurewathanakul, C.; Kirn, T.; Klaver, N. S.; Klimaszewski, K.; Koliiev, S.; Kolpin, M.; Komarov, I.; Koppenburg, P.; Kosmyntseva, A.; Kozachuk, A.

    2017-01-01

    Decays of the Xi(-)(b) and Omega(-)(b) baryons to the charmless final states ph(-)h'(-), where h((')) denotes a kaon or pion, are searched for with the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies root s = 7 and 8 TeV,

  8. Kaon and pion production in centrality selected minimum bias Pb+Pb collisions at 40 and 158 A.GeV

    Energy Technology Data Exchange (ETDEWEB)

    Dinkelaker, Peter

    2009-07-01

    Results on charged kaon and negatively charged pion production and spectra for centrality selected Pb+Pb minimum bias events at 40 and 158A GeV have been presented in this thesis. All analysis are based on data taken by the NA49 experiment at the accelerator Super Proton Synchrotron (SPS) at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. The kaon results are based on an analysis of the mean energy loss of the charged particles traversing the detector gas of the time projection chambers (TPCs). The pion results are from an analysis of all negatively charged particles h{sup -} corrected for contributions from particle decays and secondary interactions. For the dE/dx analysis of charged kaons, main TPC tracks with a total momentum between 4 and 50 GeV have been analyzed in logarithmic momentum log(p) and transverse momentum p{sub t} bins. The resulting dE/dx spectra have been fitted by the sum of 5 Gaussians, one for each main particle type (electrons, pions, kaons, protons, deuterons). The amplitude of the Gaussian used for the kaon part of the spectra has been corrected for efficiency and acceptance and the binning has been transformed to rapidity y and transverse momentum pt bins. The multiplicity dN/dy of the single rapidity bins has been derived by summing the measured range of the transverse momentum spectra and an extrapolation to full coverage with a single exponential function fitted to the measured range. The results have been combined with the mid-rapidity measurements from the time-of-flight detectors and a double Gaussian fit to the dN/dy spectra has been used for extrapolation to rapidity outside of the acceptance of the dE/dx analysis. For the h{sup -} analysis of negatively charged pions, all negatively charged tracks have been analyzed. The background from secondary reactions, particle decays, and gamma-conversions has been corrected with the VENUS event generator. The results were also corrected for efficiency

  9. Search for Invisible Decays of a Light Scalar in Radiative Transitions Y(3S)->gamma A0

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B

    2008-11-05

    We search for a light scalar particle produced in single-photon decays of the {Upsilon}(3S) resonance through the process {Upsilon}(3S) {yields} {gamma} + A{sup 0}, A{sup 0} {yields} invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A{sup 0} could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of {Upsilon}(3S). We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range m{sub A{sup 0}} {le} 7.8 GeV. The results are preliminary.

  10. B Decay Studies at SLD

    Energy Technology Data Exchange (ETDEWEB)

    Convery, Mark R

    1999-03-19

    We present three preliminary results from SLD on B decays: an inclusive search for the process b {r_arrow} s gluon, a measurement of the branching ratio for the process B {r_arrow} D{bar D}X, and measurements of the charged and neutral B lifetimes. All three measurements make use of the excellent vertexing efficiency and resolution of the CCD Vertex Detector and the first two make use of the excellent particle identification capability of the Cherenkov Ring Imaging Detector. The b {r_arrow} sg analysis searches for an enhancement of high momentum charged kaons produced in B decays. Within the context of a simple, Jetset-inspired model of b {r_arrow} sg, a limit of B(b {r_arrow} sg) < 7.6% is obtained. The B(B {r_arrow} D{bar D}X) analysis reconstructs two secondary vertices and uses identified charged kaons to determine which of these came from charm decays. The result of the analysis is B(B {r_arrow} D{bar D}X) = (16.2 {+-} 1.9 {+-} 4.2)%. The results of the lifetime analysis are: {tau}{sub B{sup +}} = 1.686 {+-} 0.025 {+-} 0.042 ps, {tau}{sub B{sup 0}} = 1.589 {+-} 0.026 {+-} 0.055 ps and {tau}{sub B{sup +}}/{tau}{sub B{sup 0}} = 1.061 {+-} 0.031/0.029 {+-} 0.027.

  11. Measurements of Rn-222, Rn-220 and their decay products in the environmental air of the high background radiation areas in Yangjiang, China.

    Science.gov (United States)

    Yuan, Y; Morishima, H; Shen, T; Koga, T; Wei, L; Sugahara, T

    2000-10-01

    For the renewal of dose estimation from internal irradiation in the high background radiation areas (HBRA) of Yangjiang, the measurements of radon, thoron and their decay products in the environmental air were conducted, including: (1) integrating measurements of Rn-222 and Rn-220 concentrations; (2) eqilibrium factor F for Rn-222 and alpha-potential energy value of Rn-220; (3) external gamma radiation in places where radon measurements were undertaken; (4) cumulative exposure to indoor radon for each family in a case-control study on lung cancer. The Rn-Tn cup monitor method was used for the integrating measurement of Rn-222 and Rn-220 concentration. An alpha track detector was used for the integration measurement of Rn-222 concentration in the case-control study on lung cancer. The results of measurements show that although the investigated areas are located between the Equator and the Tropic of Cancer, and that people live in well-ventilated dwellings, the concentrations of radon, especially of Rn-220 are significantly higher in the indoor air of HBRA than those in the control area. The value of equilibrium factors for Rn-222, the alpha potential energy of decay products from Rn-222 and Rn-220 are determined.

  12. Measurements of Rn-222, Rn-220 and their decay products in the environmental air of the high background radiation areas in Yangjiang, China

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Yongling; Shen Tong [Labor Hygiene Inst. of Human Province, Changsha (China); Morishima, Hiroshige; Koga, Taeko; Wei Luxin; Sugahara, Tsutomu

    2000-10-01

    For the renewal of dose estimation from internal irradiation in the high background radiation areas (HBRA) of Yangjiang, the measurements of radon, thoron and their decay products in the environmental air were conducted, including: integrating measurements of Rn-222 and Rn-220 concentrations; equilibrium factor F for Rn-222 and alpha-potential energy value of Rn-220; external gamma radiation in places where radon measurements were undertaken; cumulative exposure to indoor radon for each family in a case-control study on lung cancer. The Rn-Tn cup monitor method was used for the integrating measurement of Rn-222 and Rn-220 concentration. An alpha track detector was used for the integration measurement of Rn-222 concentration in the case-control study on lung cancer. The results of measurements show that although the investigated areas are located between the Equator and the Tropic of Cancer, and that people live in well-ventilated dwellings, the concentrations of radon, especially of Rn-220 are significantly higher in the indoor air of HBRA than those in the control area. The value of equilibrium factors for Rn-222, the alpha potential energy of decay products from Rn-222 and Rn-220 are determined. (author)

  13. Magnetic field effects on the Rabi splitting and radiative decay rates of the exciton-polariton states in a semiconductor microcavity

    Science.gov (United States)

    Fenniche, H.; Jaziri, S.; Bennaceur, R.

    1998-12-01

    We study theoretically a particular type of semiconductor microcavity formed by a quantum well embedded inside it and the distributed Bragg reflectors presenting a gradual structure. We apply to this structure a static magnetic field along the growth direction. In the strong coupling regime between the confined exciton and cavity modes, we evaluate the polariton Rabi splitting corresponding to the two lowest lying exciton states: HH1-CB1 and HH2-CB2 as a function of the applied magnetic field. In high magnetic field and for distinct reflectivities, we find that the Rabi splitting magnitude of the HH2-CB2 exciton is close to the fundamental one (HH1-CB1). In the presence of the magnetic field, the polariton Rabi splitting can be obtained even in low reflectivity. The dispersion polariton radiative decay rates related to the two lowest lying exciton states: HH1-CB1 and HH2-CB2 are calculated for different magnetic field values. At k //=0 and in the weak coupling regime, the polariton radiative decay rates are evaluated for both the HH1-CB1 and HH2-CB2 excitons. We show that for the fundamental excitonic state, the magnetic field value which determines the transition from the weak to the strong coupling regime is different from the HH2-CB2 exciton state.