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Sample records for antiproton radiotherapy measurements

  1. Antiproton radiotherapy

    CERN Document Server

    Bassler, Niels; Beyer, Gerd; DeMarco, John J.; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Iwamoto, Keisuke S.; Jakel, Oliver; Knudsen, Helge V.; Kovacevic, Sandra; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen B.à; Solberg, Timothy D.; Sørensen, Brita S.; Vranjes, Sanja; Wouters, Bradly G.; Holzscheiter, Michael H.

    2008-01-01

    Antiprotons are interesting as a possible future modality in radiation therapy for the following reasons: When fast antiprotons penetrate matter, protons and antiprotons have near identical stopping powers and exhibit equal radiobiology well before the Bragg-peak. But when the antiprotons come to rest at the Bragg-peak, they annihilate, releasing almost 2 GeV per antiproton–proton annihilation. Most of this energy is carried away by energetic pions, but the Bragg-peak of the antiprotons is still locally augmented with ∼20–30 MeV per antiproton. Apart from the gain in physical dose, an increased relative biological effect also has been observed, which can be explained by the fact that some of the secondary particles from the antiproton annihilation exhibit high-LET properties. Finally, the weakly interacting energetic pions, which are leaving the target volume, may provide a real time feedback on the exact location of the annihilation peak. We have performed dosimetry experiments and investigated the rad...

  2. Neutron fluence in antiproton radiotherapy, measurements and simulations

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael H.; Petersen, Jørgen B.B.

    2010-01-01

    A significant part of the secondary particle spectrum from antiproton annihilation consists of fast neutrons, which may contribute to a significant dose background found outside the primary beam. Using a polystyrene phantom as a moderator, we have performed absolute measurements of the thermalized...... part of the fast neutron spectrum using Lithium-6 and -7 Fluoride TLD pairs. The experimental results are found to be in good agreement with simulations using the Monte Carlo particle transport code FLUKA. The thermal neutron kerma resulting from the measured thermal neutron fluence is insignificant...

  3. A systematic review of antiproton radiotherapy

    Directory of Open Access Journals (Sweden)

    Martin-Immanuel eBittner

    2014-01-01

    Full Text Available Antiprotons have been proposed as possible particles for radiotherapy; over the past years, the renewed interest in the potential biomedical relevance led to an increased research activity. It is the aim of this review to deliver a comprehensive overview regarding the evidence accumulated so far, analysing the background and depicting the current status of antiprotons in radiotherapy. A literature search has been conducted, including major scientific and commercial databases. All articles and a number of relevant conference abstracts published in the respective field have been included in this systematic review. The physical basis of antiproton radiotherapy is complex; however, the characterisation of the energy deposition profile supports its potential use in radiotherapy. Also the dosimetry improved considerably over the past few years. Regarding the biological properties, data on the effects on cells are presented; however, definite conclusions regarding the relative biological effectiveness cannot be made at the moment and radiobiological evidence of enhanced effectiveness remains scarce. In addition, there is new evidence supporting the potential imaging properties, for example for online dose verification. Clinical settings which might profit from the use of antiprotons have been further tracked. Judging from the evidence available so far, clinical constellations requiring optimal sparing in the entrance region of the beam and re-irradiations might profit most from antiproton radiotherapy. While several open questions remain to be answered, first steps towards a thorough characterisation of this interesting modality have been made.

  4. Antiproton compression and radial measurements

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jorgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page R D; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wurtele, J S; Yamazaki, Y

    2008-01-01

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, achieved by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile, and its relation to that of the electron plasma. We also measure the outer radial profile by ejecting antiprotons to the trap wall using an octupole magnet.

  5. Measurement of interaction between antiprotons

    Science.gov (United States)

    The Star Collaboration; Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Bairathi, V.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandenburg, J. D.; Brandin, A. V.; Bunzarov, I.; Butterworth, J.; Caines, H.; Calderón de La Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Contin, G.; Crawford, H. J.; Das, S.; de Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Z.; Filip, P.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Haque, R.; Harris, J. W.; He, L.; Heppelmann, S.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Jiang, K.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikoła, D. P.; Kisel, I.; Kisiel, A.; Klein, S.; Kochenda, L.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, X.; Li, Z. M.; Li, Y.; Li, W.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R.; Ma, Y. G.; Ma, L.; Magdy, N.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Meehan, K.; Minaev, N. G.; Mioduszewski, S.; Mishra, D.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D.; Page, B. S.; Pak, R.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlik, B.; Pei, H.; Perkins, C.; Peterson, A.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, M. K.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stepanov, M.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B.; Sun, Z.; Sun, X. M.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, N.; Szelezniak, M. A.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Y.; Wang, Y.; Wang, F.; Webb, J. C.; Webb, G.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z. G.; Xie, W.; Xin, K.; Xu, Y. F.; Xu, Q. H.; Xu, H.; Xu, N.; Xu, Z.; Yang, Y.; Yang, C.; Yang, S.; Yang, Y.; Yang, Q.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, Z.; Zhang, J.; Zhang, S.; Zhang, X. P.; Zhang, J.; Zhang, Y.; Zhao, J.; Zhong, C.; Zhou, L.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.

    2015-11-01

    One of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force that has since been acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, little is known directly about the nuclear force between antinucleons. Here, we study antiproton pair correlations among data collected by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC), where gold ions are collided with a centre-of-mass energy of 200 gigaelectronvolts per nucleon pair. Antiprotons are abundantly produced in such collisions, thus making it feasible to study details of the antiproton-antiproton interaction. By applying a technique similar to Hanbury Brown and Twiss intensity interferometry, we show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: the scattering length and the effective range of the interaction. Our measured parameters are consistent within errors with the corresponding values for proton-proton interactions. Our results provide direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, and so are fundamental to understanding the structure of more-complex antinuclei and their properties.

  6. Antiproton radiotherapy: peripheral dose from secondary neutrons

    DEFF Research Database (Denmark)

    Fahimian, Benjamin P.; DeMarco, John J.; Keyes, Roy

    2009-01-01

    is the normal tissue dose resulting from secondary neutrons produced in the annihilation of antiprotons on the nucleons of the target atoms. Here we present the first organ specific Monte Carlo calculations of normal tissue equivalent neutron dose in antiproton therapy through the use of a segmented CT......-based human phantom. The MCNPX Monte Carlo code was employed to quantify the peripheral dose for a cylindrical spread out Bragg peak representing a treatment volume of 1 cm diameter and 1 cm length in the frontal lobe of a segmented whole-body phantom of a 38 year old male. The secondary neutron organ dose...

  7. Towards an antiproton measurement with AMS-02

    Energy Technology Data Exchange (ETDEWEB)

    Bachlechner, Andreas [RWTH Aachen University (Germany)

    2015-07-01

    AMS-02 is a multi-purpose high-precision particle detector. It has been onboard the International Space Station since May 2011. The antiprotons measurement is an important part of the AMS-02 physics program. An excess above the expected spectrum due to interactions of cosmic rays with the interstellar matter can hint at exotic sources like dark matter annihilation. The antiproton-to-proton ratio and the antiproton flux itself may also improve the understanding of the origin and propagation of cosmic rays. Due to the very small fraction of antiprotons in the cosmic radiation of about 10{sup -5} compared to protons a very precise particle identification is needed. The main backgrounds are other singly charged particles like protons, electrons, and pions produced within the detector material itself. At lower energies the ring-imaging Cherenkov detector and the time-of-flight system help to separate light particles from protons. The electromagnetic calorimeter and the transition radiation detector redundantly suppress the electron background. The reconstruction of the charge sign by the magnetic spectrometer is limited by its resolution and has to be taken into account carefully. The strategies to identify antiprotons in the cosmic-ray measurement in different energy regions are presented. Methods to suppress and the effect of the backgrounds to the antiproton-to-proton ratio are discussed.

  8. Antiproton Radiotherapy Peripheral Dose from Secondary Neutrons produced in the Annihilation of Antiprotons in the Target

    CERN Document Server

    Fahimian, Benjamin P; Keyes, Roy; Bassler, Niels; Iwamoto, Keisuke S; Zankl, Maria; Holzscheiter, Michael H

    2009-01-01

    The AD-4/ACE collaboration studies the biological effects of antiprotons with respect to a possible use of antiprotons in cancer therapy. In vitro experiments performed by the collaboration have shown an enhanced biological effectiveness for antiprotons relative to protons. One concern is the normal tissue dose resulting from secondary neutrons produced in the annihilation of antiprotons on the nucleons of the target atoms. Here we present the first organ specific Monte Carlo calculations of normal tissue equivalent neutron dose in antiproton therapy through the use of a segmented CT-based human phantom. The MCNPX Monte Carlo code was employed to quantify the peripheral dose for a cylindrical spread out Bragg peak representing a treatment volume of 1 cm diameter and 1 cm length in the frontal lobe of a segmented whole-body phantom of a 38 year old male. The secondary neutron organ dose was tallied as a function of energy and organ.

  9. Precision measurement of antiprotonic hydrogen and deuterium X-rays

    Science.gov (United States)

    Heitlinger, K.; Bacher, R.; Badertscher, A.; Blüm, P.; Eades, J.; Egger, J.; Elsener, K.; Gotta, D.; Morenzoni, E.; Simons, L. M.

    1992-09-01

    X-rays from antiprotonic hydrogen and deuterium have been measured at low pressures. Using the cyclotron trap, a 105 MeV/c antiproton beam from LEAR was stopped with an efficiency of 86% in 30 mbar hydrogen gas in a volume of only 100 cm3. The X-rays were measured with Si(Li) detectors and a Xe-CH4 drift chamber. The strong interaction shift and broadening of the Lyman α transition and the spin-averaged 2p width in antiprotonic hydrogen was measured with unprecedented accuracy. The triplet component of the ground state in antiprotonic hydrogen was determined for the first time.

  10. Measurement of strong interaction effects in antiprotonic helium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Davies, J.D.; Gorringe, T.P.; Lowe, J.; Nelson, J.M.; Playfer, S.M.; Pyle, G.J.; Squier, G.T.A. (Birmingham Univ. (UK). Dept. of Physics); Baker, C.A.; Batty, C.J.; Clark, S.A.

    1984-09-27

    The strong interaction shift and width for the 2 p level and the width for the 3d level have been measured for antiprotonic helium atoms. The results are compared with optical model calculations. The possible existence of strongly bound antiproton states in nuclei is discussed.

  11. Precision measurement of antiprotonic hydrogen and deuterium X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Heitlinger, K.; Bluem, P. (Kernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Kernphysik Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Experimentelle Kernphysik); Bacher, R.; Badertscher, A.; Egger, J.; Morenzoni, E.; Simons, L.M. (Paul Scherrer Inst. (PSI), Villigen (Switzerland)); Eades, J.; Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland)); Gotta, D. (Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik)

    1992-05-01

    X-rays from antiprotonic hydrogen and deuterium have been measured at low pressures. Using the cylcotron trap, a 105 MeV/c antiproton beam from LEAR was stopped with an efficiency of 86% in 30 mbar hydrogen gas in a volume of only 100 cm{sup 3}. The X-rays were measured with Si(Li) detectors and a Xe-CH{sub 4} drift chamber. The strong interaction shift and broadening of the Lyman {alpha} transition and the spin-averaged 2p width in antiprotonic hydrogen was measured with unprecedented accuracy. The triplet component of the ground state in antiprotonic hydrogen was determined for the first time. (orig.).

  12. The Antiproton Depth Dose Curve Measured with Alanine Detectors

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, Johnny Witterseh; Palmans, Hugo;

    2008-01-01

    In this paper we report on the measurement of the antiproton depth dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen et Olsen for conversion of calculated dose...

  13. Neutrons from Antiproton Irradiation

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael; Petersen, Jørgen B.B.

    Background: Radiotherapy with Antiprotons is currently investigated by the AD-4/ACE collaboration. The hypothesis is that the additional energy released from the antiprotons annihilating at the target nuclei can enable a reduced dose in the entry channel of the primary beam. Furthermore an enhanced...... relative biological effect (RBE) has already been beam measured in spread out Bragg peaks of antiprotons, relative to that found in the plateau region. However, the antiproton annihilation process is associated with a substantial release of secondary particles which contribute to the dose outside...... the neutron spectrum. Additionally, we used a cylindrical polystyrene loaded with several pairs of thermoluminescent detectors containing Lithium-6 and Lithium-7, which effectively detects thermalized neutrons. The obtained results are compared with FLUKA imulations. Results: The results obtained...

  14. Beam Measurement Systems for the CERN Antiproton Decelerator (AD)

    CERN Document Server

    Angoletta, Maria Elena; Ludwig, M; Marqversen, O; Odier, P; Pedersen, F; Raich, U; Søby, L; Tranquille, G; Spickermann, T

    2001-01-01

    The new, low-energy antiproton physics facility at CERN has been successfully commissioned and has been delivering decelerated antiprotons at 100 MeV/c since July 2000. The AD consists of one ring where the 3.5 GeV/c antiprotons produced from a production target are injected, rf manipulated, stochastically cooled, decelerated (with further stages involving additional stochastic and electron cooling and rf manipulation) and extracted at 100 MeV/c. While proton test beams of sufficient intensity could be used for certain procedures in AD commissioning, this was not possible for setting-up and routine operation. Hence, special diagnostics systems had to be developed to obtain the beam and accelerator characteristics using the weak antiproton beams of a few 10E7 particles at all momenta from 3.5 GeV/c down to 100 MeV/c. These include systems for position measurement, intensity, beam size measurements using transverse aperture limiters and scintillators and Schottky-based tools. This paper gives an overall view of...

  15. Antiproton therapy

    CERN Document Server

    Knudsen, Helge V; Bassler, Niels; Alsner, Jan; Beyer, Gerd-Jürgen; DeMarco, John J; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Iwamoto, Keisuke S; Jäkel, Oliver; Kovacevic, Sandra; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen B; Ratib, Osman; Solberg, Timothy D; Vranjes, Sanja; Wouters, Bradly G

    2008-01-01

    Radiotherapy is one of the most important means we have for the treatment of localised tumours. It is therefore essential to optimize the technique, and a lot of effort goes into this endeavour. Since the proposal by Wilson in 1946 [R.R. Wilson, Radiology use of fast protons, Radiology 47 (1946) 487.] that proton beams might be better than photon beams at inactivating cancer cells, hadron therapy has been developed in parallel with photon therapy and a substantial knowledge has been gained on the effects of pions, protons and heavy ions (mostly carbon ions). Here we discuss the recent measurements by the CERN ACE collaboration of the biological effects of antiprotons, and argue that these particles very likely are the optimal agents for radiotherapy.

  16. Antiproton beam profile measurements using Gas Electron Multipliers

    CERN Document Server

    Pinto, Serge Duarte; Spanggaard, Jens; Tranquille, Gerard

    2011-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X_0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEgIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  17. Simulation of an antiprotons beam applied to the radiotherapy; Simulacao de um feixe de antiprotons aplicado a radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Prata, Leonardo de Almeida

    2006-07-15

    Results for the interaction of a antiproton beam with constituent nuclei of the organic matter are presented. This method regards of the application of an computational algorithm to determine quantitatively the differential cross sections for the scattered particles, starting from the interaction of these antiprotons with the nuclei, what will allow in the future to draw the isodose curve for antiproton therapy, once these beams are expected to be used in cancer treatment soon. The calculation will be done through the application of the concepts of the method of intranuclear cascade, providing yield and differential cross sections of the scattered particles, present in the software MCMC. Th algorithm was developed based on Monte Carlo's method, already taking into account a validate code. The following physical quantities are presented: the yield of secondary particles, their spectral and angular distributions for these interactions. For the energy range taken into account the more important emitted particles are protons, neutrons and pions. Results shown that emitted secondary particles can modify the isodose curves, because they present high yield and energy for transverse directions. (author)

  18. Measurement of cosmic-ray antiproton spectrum at solar minimum with a long-duration balloon flight in Antarctica

    CERN Document Server

    Abe, K; Haino, S; Hams, T; Hasegawa, M; Horikoshi, A; Kim, K C; Kusumoto, A; Lee, M H; Makida, Y; Matsuda, S; Matsukawa, Y; Mitchell, J W; Nishimura, J; Nozaki, M; Orito, R; Ormes, J F; Sakai, K; Sasaki, M; Seo, E S; Shinoda, R; Streitmatter, R E; Suzuki, J; Tanaka, K; Thakur, N; Yamagami, T; Yamamoto, A; Yoshida, T; Yoshimura, K

    2011-01-01

    The energy spectrum of cosmic-ray antiprotons has been measured in the range 0.17 to 3.5 GeV, based on 7886 antiprotons collected by the BESS-Polar II instrument during a long-duration flight over Antarctica in the solar minimum period of December 2007 through January 2008. The antiproton spectrum measured by BESS-Polar II shows good consistency with secondary antiproton calculations. Cosmologically primary antiprotons have been searched for by comparing the observed and calculated antiproton spectra. The BESS-Polar II result shows no evidence of primary antiprotons originating from the evaporation of PBH.

  19. The antiproton depth–dose curve measured with alanine detectors

    CERN Document Server

    Bassler, Niels; Palmans, Hugo; Holzscheiter, Michael H; Kovacevic, Sandra

    2008-01-01

    n this paper we report on the measurement of the antiproton depth–dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen and Olsen for conversion of calculated dose into response. A good agreement is observed between the measured and calculated relative effectiveness although an underestimation of the measured values beyond the Bragg-peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use of the alanine detectors for dosimetry of mixed radiation fields.

  20. Bubble detector measurements of a mixed radiation field from antiproton annihilation

    CERN Document Server

    Bassler, Niels; Møller, Søren Pape; Petersen, Jørgen B.; Rahbek, Dennis; Uggerhøj, Ulrik I.

    2006-01-01

    In the light of recent progress in the study of the biological potential of antiproton tumour treatment it is important to be able to characterize the neutron intensity arising from antiproton annihilation using simple, compact and reliable detectors. The intensity of fast neutrons from antiproton annihilation on polystyrene has been measured with bubble detectors and a multiplicity has been derived as well as an estimated neutron equivalent dose. Additionally the sensitivity of bubble detectors towards protons was measured.

  1. Measurement method of the antiproton gravitational mass using the single electron transistor

    Energy Technology Data Exchange (ETDEWEB)

    Bouchiat, V.; Chardin, G.; Devoret, M.H.; Esteve, D.

    1996-12-31

    We propose a non destructive method to measure the trajectory of a single antiproton in a drift tube using position sensors based on the single electron transistor. We show that this recently developed device has sufficient sensitivity to detect the electric field of a moving charged particle. Comparing the trajectories of antiprotons and H{sup -} ions could allow a reliable determination of the gravitational mass of the antiproton. (authors). 24 refs.

  2. Experimental setup and first measurement of DNA damage induced along and around an antiproton beam

    DEFF Research Database (Denmark)

    Kavanagh, J. N.; Currell, F. J.; Timson, D. J.;

    2010-01-01

    Radiotherapy employs ionizing radiation to induce lethal DNA lesions in cancer cells while minimizing damage to healthy tissues. Due to their pattern of energy deposition, better therapeutic outcomes can, in theory, be achieved with ions compared to photons. Antiprotons have been proposed to offe...

  3. Comparison of electromagnetic and hadronic models generated using Geant 4 with antiproton dose measured in CERN.

    Science.gov (United States)

    Tavakoli, Mohammad Bagher; Reiazi, Reza; Mohammadi, Mohammad Mehdi; Jabbari, Keyvan

    2015-01-01

    After proposing the idea of antiproton cancer treatment in 1984 many experiments were launched to investigate different aspects of physical and radiobiological properties of antiproton, which came from its annihilation reactions. One of these experiments has been done at the European Organization for Nuclear Research known as CERN using the antiproton decelerator. The ultimate goal of this experiment was to assess the dosimetric and radiobiological properties of beams of antiprotons in order to estimate the suitability of antiprotons for radiotherapy. One difficulty on this way was the unavailability of antiproton beam in CERN for a long time, so the verification of Monte Carlo codes to simulate antiproton depth dose could be useful. Among available simulation codes, Geant4 provides acceptable flexibility and extensibility, which progressively lead to the development of novel Geant4 applications in research domains, especially modeling the biological effects of ionizing radiation at the sub-cellular scale. In this study, the depth dose corresponding to CERN antiproton beam energy by Geant4 recruiting all the standard physics lists currently available and benchmarked for other use cases were calculated. Overall, none of the standard physics lists was able to draw the antiproton percentage depth dose. Although, with some models our results were promising, the Bragg peak level remained as the point of concern for our study. It is concluded that the Bertini model with high precision neutron tracking (QGSP_BERT_HP) is the best to match the experimental data though it is also the slowest model to simulate events among the physics lists.

  4. Comparison of electromagnetic and hadronic models generated using Geant 4 with antiproton dose measured in CERN

    Directory of Open Access Journals (Sweden)

    Mohammad Bagher Tavakoli

    2015-01-01

    Full Text Available After proposing the idea of antiproton cancer treatment in 1984 many experiments were launched to investigate different aspects of physical and radiobiological properties of antiproton, which came from its annihilation reactions. One of these experiments has been done at the European Organization for Nuclear Research known as CERN using the antiproton decelerator. The ultimate goal of this experiment was to assess the dosimetric and radiobiological properties of beams of antiprotons in order to estimate the suitability of antiprotons for radiotherapy. One difficulty on this way was the unavailability of antiproton beam in CERN for a long time, so the verification of Monte Carlo codes to simulate antiproton depth dose could be useful. Among available simulation codes, Geant4 provides acceptable flexibility and extensibility, which progressively lead to the development of novel Geant4 applications in research domains, especially modeling the biological effects of ionizing radiation at the sub-cellular scale. In this study, the depth dose corresponding to CERN antiproton beam energy by Geant4 recruiting all the standard physics lists currently available and benchmarked for other use cases were calculated. Overall, none of the standard physics lists was able to draw the antiproton percentage depth dose. Although, with some models our results were promising, the Bragg peak level remained as the point of concern for our study. It is concluded that the Bertini model with high precision neutron tracking (QGSP_BERT_HP is the best to match the experimental data though it is also the slowest model to simulate events among the physics lists.

  5. Measurement of the antiproton stopping power of gold - the Barkas effect

    Science.gov (United States)

    Medenwaldt, R.; Møller, S. P.; Uggerhøj, E.; Worm, T.; Hvelplund, P.; Knudsen, H.; Elsener, K.; Morenzoni, E.

    1991-05-01

    The stopping power of gold has been measured for antiprotons in the energy range 0.2-3 MeV using a novel time-of-flight technique. The antiproton stopping power is found to be less than half the equivalent proton stopping power near the electronic stopping power maximum. In the high-energy limit the two stopping powers merge.

  6. Measurement of the antiproton stopping power of gold - the Barkas effect

    Energy Technology Data Exchange (ETDEWEB)

    Medenwaldt, R.; Moeller, S.P.; Uggerhoej, E.; Worm, T. (Inst. for Synchrotron Radiation, Aarhus Univ. (Denmark)); Hvelplund, P.; Knudsen, H. (Inst. of Physics, Univ. of Aarhus (Denmark)); Elsener, K. (CERN, Geneva (Switzerland)); Morenzoni, E. (Paul Scherrer Inst., Villigen (Switzerland))

    1991-05-06

    The stopping power of gold has been measured for antiprotons in the energy range 0.2-3 MeV using a novel time-of-flight technique. The antiproton stopping power is found to be less than half the equivalent proton stopping power near the electronic stopping power maximum. In the high-energy limit the two stopping powers merge. (orig.).

  7. Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations

    CERN Document Server

    Sótér, A; Kobayashi, T; Barna, D; Horvath, D; Hori, M

    2014-01-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) experiment at the Antiproton Decelerator (AD) facility of CERN constructed segmented scintillators to detect and track the charged pions which emerge from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. A system of 541 cast and extruded scintillator bars were arranged in 11 detector modules which provided a spatial resolution of 17 mm. Green wavelength-shifting fibers were embedded in the scintillators, and read out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The photoelectron yields of various scintillator configurations were measured using a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the AD. Nonlinear effects due to the saturation of the silicon photomultiplier were seen a...

  8. First measurement of the antiproton-nucleus annihilation cross section at 125 keV

    CERN Document Server

    Aghai-Khozani, H; Corradini, M; De Salvador, D; Hayano, R; Hori, M; Kobayashi, T; Leali, M; Lodi-Rizzini, E; Mascagna, V; Prest, M; Seiler, D; Soter, A; Todoroki, K; Vallazza, E; Venturelli, L

    2015-01-01

    The first observation of in-flight antiproton-nucleus annihilation at ∼130 keV obtained with the ASACUSA detector has demonstrated that the measurement of the cross section of the process is feasible at such extremely low energies Aghai-Khozani, H., et al., Eur. Phys. J. Plus 127, 55 (2012). Here we present the results of the data analysis with the evaluations of the antiproton annihilation cross sections on carbon, palladium and platinum targets at 125 keV.

  9. Measurement of inclusive antiprotons from Au+Au collisions at square root of s(NN) = 130 GeV.

    Science.gov (United States)

    Adler, C; Ahammed, Z; Allgower, C; Amonett, J; Anderson, B D; Anderson, M; Averichev, G S; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellwied, R; Berger, J; Bichsel, H; Bland, L C; Blyth, C O; Bonner, B E; Boucham, A; Brandin, A; Cadman, R V; Caines, H; Calderón de la Barca Sánchez, M; Cardenas, A; Carroll, J; Castillo, J; Castro, M; Cebra, D; Chattopadhyay, S; Chen, M L; Chen, Y; Chernenko, S P; Cherney, M; Chikanian, A; Choi, B; Christie, W; Coffin, J P; Cormier, T M; Cramer, J G; Crawford, H J; DeMello, M; Deng, W S; Derevschikov, A A; Didenko, L; Draper, J E; Dunin, V B; Dunlop, J C; Eckardt, V; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Fachini, P; Faine, V; Filimonov, K; Finch, E; Fisyak, Y; Flierl, D; Foley, K J; Fu, J; Gagliardi, C A; Gagunashvili, N; Gans, J; Gaudichet, L; Germain, M; Geurts, F; Ghazikhanian, V; Grabski, J; Grachov, O; Grigoriev, V; Guedon, M; Gushin, E; Hallman, T J; Hardtke, D; Harris, J W; Heffner, M; Heppelmann, S; Herston, T; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horsley, M; Huang, H Z; Humanic, T J; Hümmler, H; Igo, G; Ishihara, A; Ivanshin, Y I; Jacobs, P; Jacobs, W W; Janik, M; Johnson, I; Jones, P G; Judd, E; Kaneta, M; Kaplan, M; Keane, D; Kisiel, A; Klay, J; Klein, S R; Klyachko, A; Konstantinov, A S; Kotchenda, L; Kovalenko, A D; Kramer, M; Kravtsov, P; Krueger, K; Kuhn, C; Kulikov, A I; Kunde, G J; Kunz, C L; Kutuev, R K; Kuznetsov, A A; Lakehal-Ayat, L; Lamas-Valverde, J; Lamont, M A; Landgraf, J M; Lange, S; Lansdell, C P; Lasiuk, B; Laue, F; Lebedev, A; Lednický, R; Leontiev, V M; LeVine, M J; Li, Q; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, L; Liu, Z; Liu, Q J; Ljubicic, T; Llope, W J; LoCurto, G; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Lynn, D; Majka, R; Margetis, S; Martin, L; Marx, J; Matis, H S; Matulenko, Y A; McShane, T S; Meissner, F; Melnick, Y; Meschanin, A; Messer, M; Miller, M L; Milosevich, Z; Minaev, N G; Mitchell, J; Moiseenko, V A; Moore, C F; Morozov, V; de Moura, M M; Munhoz, M G; Mutchler, G S; Nelson, J M; Nevski, P; Nikitin, V A; Nogach, L V; Norman, B; Nurushev, S B; Odyniec, G; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Paic, G; Pandey, S U; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Perevoztchikov, V; Peryt, W; Petrov, V A; Platner, E; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potrebenikova, E; Prindle, D; Pruneau, C; Radomski, S; Rai, G; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J G; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Roy, C; Rykov, V; Sakrejda, I; Sandweiss, J; Saulys, A C; Savin, I; Schambach, J; Scharenberg, R P; Schmitz, N; Schroeder, L S; Schüttauf, A; Schweda, K; Seger, J; Seliverstov, D; Seyboth, P; Shahaliev, E; Shestermanov, K E; Shimanskii, S S; Shvetcov, V S; Skoro, G; Smirnov, N; Snellings, R; Sowinski, J; Spinka, H M; Srivastava, B; Stephenson, E J; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Struck, C; Suaide, A A; Sugarbaker, E; Suire, C; Sumbera, M; Symons, T J; de Toledo, A S; Szarwas, P; Takahashi, J; Tang, A H; Thomas, J H; Thompson, M; Tikhomirov, V; Trainor, T A; Trentalange, S; Tribble, R E; Tokarev, M; Tonjes, M B; Trofimov, V; Tsai, O; Turner, K; Ullrich, T; Underwood, D G; Van Buren, G; VanderMolen, A M; Vanyashin, A; Vasilevski, I M; Vasiliev, A N; Vigdor, S E; Voloshin, S A; Wang, F; Ward, H; Watson, J W; Wells, R; Wenaus, T; Westfall, G D; Whitten, C; Wieman, H; Willson, R; Wissink, S W; Witt, R; Xu, N; Xu, Z; Yakutin, A E; Yamamoto, E; Yang, J; Yepes, P; Yurevich, V I; Zanevski, Y V; Zborovský, I; Zhang, H; Zhang, W M; Zoulkarneev, R; Zubarev, A N

    2001-12-24

    We report the first measurement of inclusive antiproton production at midrapidity in Au+Au collisions at square root of s(NN) = 130 GeV by the STAR experiment at RHIC. The antiproton transverse mass distributions in the measured transverse momentum range of 0.25antiproton rapidity density is found to scale approximately with the negative hadron multiplicity density.

  10. Measurement of the stopping power of silicon for antiprotons between 0. 2 and 3 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Medenwaldt, R.; Moeller, S.P.; Uggerhoej, E.; Worm, T. (Inst. for Synchrotron Radiation, Aarhus Univ. (Denmark)); Hvelplund, P.; Knudsen, H. (Inst. of Physics, Aarhus Univ. (Denmark)); Elsener, K. (CERN, Geneva (Switzerland)); Morenzoni, E. (Paul Scherrer Inst., Villigen (Switzerland))

    1991-05-01

    Our previous measurement of the stopping power of silicon power of silicon for antiprotons has been extended down to 200 keV. The antiproton stopping power is found to be more than 30% lower than that for equivelocity protons at 200 keV. The ''Z{sub 1}{sup 3} contribution'' to the stopping power (the Barkas effect) is deduced by comparing the stopping power for protons and antiprotons. Comparisons to theoretical estimates are made. (orig.).

  11. Measurement of the stopping power of silicon for antiprotons between 0.2 and 3 MeV

    Science.gov (United States)

    Medenwaldt, R.; Møller, S. P.; Uggerhøj, E.; Worm, T.; Hvelplund, P.; Knudsen, H.; Elsener, K.; Morenzoni, E.

    1991-05-01

    Our previous measurement of the stopping power of silicon for antiprotons has been extended down to 200 keV. The antiproton stopping power is found to be more than 30% lower than that for equivelocity protons at 200 keV. The " Z13 contribution" to the stopping power (the Barkas effect) is deduced by comparing the stopping power for protons and antiprotons. Comparisons to theoretical estimates are made.

  12. Measurement of the Z31 contribution to the stopping power using MeV protons and antiprotons: The Barkas effect

    Science.gov (United States)

    Andersen, L. H.; Hvelplund, P.; Knudsen, H.; Möller, S. P.; Pedersen, J. O. P.; Uggerhöj, E.; Elsener, K.; Morenzoni, E.

    1989-04-01

    The stopping power for antiprotons has been measured for the first time. The antiproton stopping power of silicon is found to be 3%-19% lower than for equivelocity protons over the energy range 3.01 to 0.538 MeV. The ``Z31 contribution'' to the stopping power (the Barkas effect) is deduced by comparing the stopping power for protons and antiprotons.

  13. First measurement of the antiproton-nucleus annihilation cross section at 125 keV

    Energy Technology Data Exchange (ETDEWEB)

    Aghai-Khozani, H. [Max-Planck-Institut fur Quantenoptik (Germany); Barna, D. [CERN (Switzerland); Corradini, M. [Università degli Studi di Brescia, Dipartimento di Ingegneria dell’Informazione (Italy); Salvador, D. De [Università di Padova, Dipartimento di Fisica e Astronomia (Italy); Hayano, R. [University of Tokyo, Department of Physics (Japan); Hori, M. [Max-Planck-Institut fur Quantenoptik (Germany); Kobayashi, T. [University of Tokyo, Department of Physics (Japan); Leali, M.; Lodi-Rizzini, E.; Mascagna, V. [Università degli Studi di Brescia, Dipartimento di Ingegneria dell’Informazione (Italy); Prest, M. [Università degli Studi dell’Insubria, Dipartimento di Scienza e Alta Tecnologia (Italy); Seiler, D. [TUM Department of Physics E12 (Germany); Soter, A. [Max-Planck-Institut fur Quantenoptik (Germany); Todoroki, K. [University of Tokyo, Department of Physics (Japan); Vallazza, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste (Italy); Venturelli, L., E-mail: venturelli@bs.infn.it [Università degli Studi di Brescia, Dipartimento di Ingegneria dell’Informazione (Italy)

    2015-08-15

    The first observation of in-flight antiproton-nucleus annihilation at ∼130 keV obtained with the ASACUSA detector has demonstrated that the measurement of the cross section of the process is feasible at such extremely low energies Aghai-Khozani, H., et al., Eur. Phys. J. Plus 127, 55 (2012). Here we present the results of the data analysis with the evaluations of the antiproton annihilation cross sections on carbon, palladium and platinum targets at ∼125 keV.

  14. Measurement of 0.25-3.2 GeV antiprotons in the cosmic radiation

    DEFF Research Database (Denmark)

    Mitchell, J.W.; Barbier, L.M.; Christian, E.R.;

    1996-01-01

    The balloon-borne Isotope Matter-Antimatter Experiment (IMAX) was flown from Lynn Lake, Manitoba, Canada on 16-17 July 1992. Using velocity and magnetic rigidity to determine mass, we have directly measured the abundances of cosmic ray antiprotons and protons in the energy range from 0.25 to 3.2 ...

  15. Measurement of Antiproton-proton Cross-Sections at Low Antiproton Momenta

    CERN Multimedia

    2002-01-01

    The experiment is designed to measure four different cross sections in the momentum range 150~MeV/c to 600~MeV/c: 1)~~~~the differential elastic \\\\ \\\\ 2)~~~~the differential charge exchange\\\\ \\\\ 3)~~~~the annihilation into charged and neutral pions\\\\ \\\\ 4)~~~~and the total cross section via the optical theorem. \\\\ \\\\ The experiment allows one to search once again and with good precision for baryonium. Of special interest is the existence of the S-meson, for which a signal of about 20~MeV-mb was found in a 1981 experiment (performed in the East Hall).\\\\ \\\\ A second point of special interest is the momentum region below 300~MeV/c because the cross sections are basically unknown. We will be able to explore the momentum dependence of this region for the first time.\\\\ \\\\ The elastic cross section is measured by a cylindrical multiwire proportional chamber and a scintillator hodoscope placed around a scattering chamber under vacuum. The charge exchange cross section is measured by a ring of 32~anti-neutron detector...

  16. Measurement of Balmer and Lyman X-rays in antiprotonic hydrogen isotopes at pressures below 300 hPa

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, R.; Bluem, P.; Gotta, D.; Heitlinger, K.; Rohmann, D.; Schneider, M.; Egger, J.; Simons, L.M.; Elsener, K.

    1989-09-01

    X-rays of Balmer and Lyman transitions in antiprotonic hydrogen and of Balmer transitions in antiprotonic deuterium were observed at pressures below 300 hPa using Si(Li) semiconductor detectors. The measurement was performed at the LEAR-facility at a beam momentum of 202 MeV/c. In order to stop antiprotons in a low pressure gaseous target with high efficiency, a novel technique, the cyclotron trap has been used. Absolute yields were determined and compared with cascade calculations. A distinct difference in the cascade of antiprotonic hydrogen and deuterium is found. The parameters of strong interaction in antiprotonic hydrogen are determined to be /epsilon//sub 1s/=-(620+-100) eV, /Gamma//sub 1s/=(1130+-170) eV and /Gamma//sub 2p/=(32+-10) meV. (orig.).

  17. Measurements of the Decays $B^0 \\to \\bar{D}^0\\proton\\antiproton$, $B^0 \\to \\bar{D}^{*0}\\proton\\antiproton$, $B^0 \\to D^{-}\\proton\\antiproton\\pi^+$, and $B^0 \\to D^{*-}\\proton\\antiproton\\pi^+$

    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; Pappagallo, M; 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; Day, C T; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; 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, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Goetzen, K; 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; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; 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; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; 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; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, C; Verderi, M; Bard, D J; 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; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Nash, J A; Nikolich, M B; Panduro-Vazquez, W; 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; 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; Brown, C L; Cowan, G; Flächer, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Kelly, M P; 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; Willocq, S Y; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Potter, C T; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; 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; Del Re, D; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Blount, N L; Brau, J E; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Galeazzi, F; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; 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; Behera, P K; Gladney, L; Panetta, J; Biasini, M; Covarelli, R; Pioppi, M; 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; 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; 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; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; Mayer, B; Vasseur, G; Yéche, C; Zito, M; Park, W; Purohit, M V; Weidemann, A W; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Boyarski, A M; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dong, D; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Libby, J; 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; 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; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Vitale, L; Azzolini, V; 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; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mellado, B; Mihályi, A; Mohapatra, A K; Pan, Y; Pierini, M; Prepost, R; Tan, P; Wu, S L; Yu, Z; Neal, H

    2006-01-01

    We present measurements of branching fractions of $B^0$ decays to multi-body final states containing protons, based on 232 million $\\Upsilon(4S)\\to B\\bar{B}$ decays collected with the BaBar detector at the SLAC PEP-II asymmetric-energy $B$ factory. We measure the branching fractions ${\\cal B}(B^0 \\to \\bar{D}^0\\proton\\antiproton)=(1.13\\pm0.06\\pm0.08)\\times 10^{-4}$, ${\\cal B}(B^0 \\to \\bar{D}^{*0}\\proton\\antiproton)=(1.01\\pm0.10\\pm0.09)\\times 10^{-4}$, ${\\cal B}(B^0 \\to D^{-}\\proton\\antiproton\\pi^+)=(3.38\\pm0.14\\pm0.29)\\times 10^{-4}$, and ${\\cal B}(B^0 \\to D^{*-}\\proton\\antiproton\\pi^+)=(4.81\\pm0.22\\pm0.44)\\times 10^{-4}$ where the first error is statistical and the second systematic. We present a search for the charmed pentaquark state, $\\Theta_c(3100)$ observed by H1 and put limits on the branching fraction ${\\cal B} (B^0 \\to \\Theta_c \\antiproton\\pi^+)\\times{\\cal B}(\\Theta_c \\to D^{*-}\\proton)<14\\times10^{-6}$ and ${\\cal B}(B^0 \\to \\Theta_c \\antiproton\\pi^+)\\times{\\cal B}(\\Theta_c\\to D^-\\proton)<9\\time...

  18. Nuclear Excitations by Antiprotons and Antiprotonic Atoms

    CERN Multimedia

    2002-01-01

    The proposal aims at the investigation of nuclear excitations following the absorption and annihilation of stopped antiprotons in heavier nuclei and at the same time at the study of the properties of antiprotonic atoms. The experimental arrangement will consist of a scintillation counter telescope for the low momentum antiproton beam from LEAR, a beam degrader, a pion multiplicity counter, a monoisotopic target and Ge detectors for radiation and charged particles. The data are stored by an on-line computer.\\\\ \\\\ The Ge detectors register antiprotonic x-rays and nuclear @g-rays which are used to identify the residual nucleus and its excitation and spin state. Coincidences between the two detectors will indicate from which quantum state the antiprotons are absorbed and to which nuclear states the various reactions are leading. The measured pion multiplicity characterizes the annihilation process. Ge&hyphn. and Si-telescopes identify charged particles and determine their energies.\\\\ \\\\ The experiment will gi...

  19. Instrumentation for measurement of in-flight annihilations of 130 keV antiprotons on thin target foils

    Science.gov (United States)

    Todoroki, K.; Barna, D.; Hayano, R. S.; Aghai-Khozani, H.; Sótér, A.; Corradini, M.; Leali, M.; Lodi-Rizzini, E.; Mascagna, V.; Venturelli, L.; Prest, V.; Vallazza, L.; De Salvador, D.; Hori, M.

    2016-11-01

    We describe the instrumentation for an experiment to measure the cross sections of antiprotons with kinetic energies of 130±10 keV annihilating on carbon, palladium, and platinum target foils of sub-100 nm thicknesses. A 120 ns long pulsed beam containing 105 -106 antiprotons was allowed to traverse the foils, and the signal annihilations that resulted from this were isolated using a time-of-flight method. Backgrounds arose from Rutherford scattering of the antiprotons off the target foils, their annihilations in the target chamber walls, and π → μ → e decay of the charged pions that emerged from the annihilations. Some antiprotons slowed down and annihilated in the contamination on the target surfaces. This reduced the signal-to-background ratio of the measurement.

  20. Biological Effectiveness of Antiproton Annihilation

    DEFF Research Database (Denmark)

    Maggiore, C.; Agazaryan, N.; Bassler, N.;

    2004-01-01

    from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The background, description, and status...

  1. Measurement of (anti)deuteron and (anti)proton production in DIS 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-, C; Estrada; 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

    The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300--318 GeV using an integrated luminosity of 120 pb-1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3anti)proton yield by approximately three orders of magnitude, consistent with the world measurements.

  2. Measurement of the Antiproton-Proton Total Cross-Section at the CERN ISR

    CERN Multimedia

    2002-01-01

    This experiment is a measurement of small angle scattering of antiprotons on protons and of protons on protons at 15/15, 22/22, 26/26 and 31/31 GeV, with the aim of obtaining data on the total cross-section for the scattering of protons on protons, and of determining the ratio of the real to the imaginary scattering amplitude at zero momentum transfer for antiprotons on protons. The measurement is divided into two parts: \\item 1) The measurement of @s^t^o^t(@*p) and @s^t^o^t(pp), using hodoscopes placed at small angles, outside the vacuum pipe, at approximately 9 metres from the intersection point. \\item 2) The measurement of the region in !t!, the momentum transfer squared, around the value !t^c!, where Coulomb and nuclear scattering are equal, in order to deduce the quantity @r = Re f(t=0)/Im f(t=0). This latter measurement is done by employi in earlier @s^t(pp) and @r experiments at the ISR. \\end{enumerate} In both set-ups the measurements are made by recording coincidences between collinear counters in th...

  3. Biological effectiveness of antiproton annihilation

    CERN Document Server

    Holzscheiter, Michael H.; Bassler, Niels; Beyer, Gerd; De Marco, John J.; Doser, Michael; Ichioka, Toshiyasu; Iwamoto, Keisuke S.; Knudsen, Helge V.; Landua, Rolf; Maggiore, Carl; McBride, William H.; Møller, Søren Pape; Petersen, Jorgen; Smathers, James B.; Skarsgard, Lloyd D.; Solberg, Timothy D.; Uggerhøj, Ulrik I.; Withers, H.Rodney; Vranjes, Sanja; Wong, Michelle; Wouters, Bradly G.

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in “biological dose” in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current status of the experiment are given.

  4. Biological effectiveness of antiproton annihilation

    DEFF Research Database (Denmark)

    Holzscheiter, M.H.; Agazaryan, N.; Bassler, Niels;

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct...... measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current...

  5. Measurement of small-angle antiproton-proton and proton-proton elastic scattering at the CERN intersecting storage rings

    NARCIS (Netherlands)

    Amos, N.; Block, M.M.; Bobbink, G.J.; Botje, M.A.J.; Favart, D.; Leroy, C.; Linde, F.; Lipnik, P.; Matheys, J-P.; Miller, D.

    1985-01-01

    Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at . Using the optical theorem, total cross sections are obtained with an accuracy of about

  6. Sixfold improved single particle measurement of the magnetic moment of the antiproton

    CERN Document Server

    Nagahama, H; Sellner, S; Harrington, J; Higuchi, T; Borchert, M J; Tanaka, T; Besirli, M; Mooser, A; Schneider, G; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; Ulmer, S

    2017-01-01

    Our current understanding of the Universe comes, among others, from particle physics and cosmology. In particle physics an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, a striking matter/antimatter imbalance is observed. This contradiction inspires comparisons of the fundamental properties of particles and antiparticles with high precision. Here we report on a measurement of the g-factor of the antiproton with a fractional precision of 0.8 parts per million at 95% confidence level. Our value /2=2.7928465(23) outperforms the previous best measurement by a factor of 6. The result is consistent with our proton g-factor measurement gp/2=2.792847350(9), and therefore agrees with the fundamental charge, parity, time (CPT) invariance of the Standard Model of particle physics. Additionally, our result improves coefficients of the standard model extension which discusses the sensitivity of experiments with respect to CPT violation by up to a factor of 20.

  7. Antiproton charge radius

    Science.gov (United States)

    Crivelli, P.; Cooke, D.; Heiss, M. W.

    2016-09-01

    The upcoming operation of the extra low energy antiprotons ring at CERN, the upgrade of the antiproton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of 1 08 e+ /s will open the possibility for new experiments with antihydrogen (H ¯). Here we propose a scheme to measure the Lamb shift of H ¯. For four months of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of C P T and the first determination of the antiproton charge radius at the level of 10%.

  8. Calculated LET-Spectrum of Antiprotons

    DEFF Research Database (Denmark)

    Bassler, Niels

    Introduction Antiprotons as a new beam modality in radiotherapy are being investigated by the AD-4/ACE collaboration since 2002. A beam of antiprotons hitting a water phantom exhibit a similar depth-dose curve as that known from protons, except that the Bragg-peak is significantly pronounced due...

  9. Measurement of (anti)deuteron and (anti)proton production in DIS at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2007-05-15

    The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300-318 GeV using an integrated luminosity of 120 pb{sup -1}. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3anti)proton yield by approximately three orders of magnitude, consistent with the world measurements. (orig.)

  10. Bubble detector measurements of a mixed radiation field from antiproton annihilation

    DEFF Research Database (Denmark)

    Bassler, Niels; Knudsen, Helge; Møller, Søren Pape;

    2006-01-01

    In the light of recent progress in the study of the biological potential of antiproton tumour treatment it is important to be able to characterize the neutron intensity arising from antiproton annihilation using simple, compact and reliable detectors. The intensity of fast neutrons from antiproto...

  11. Search for polarization effects in the antiproton production process

    CERN Document Server

    Grzonka, D; Ritman, J.; Sefzick, T.; Oelert, W.; Diermaier, M.; Widmann, E.; Zmeskal, J.; Glowacz, B.; Moskal, P.; Zielinski, M.; Wolke, M.; Nadel-Turonski, P.; Carmignotto, M.; Horn, T.; Mkrtchyan, H.; Asaturyan, A.; Mkrtchyan, A.; Tadevosyan, V.; Zhamkochyan, S.; Malbrunot-Ettenauer, S.; Eyrich, W.; Hauenstein, F.; Zink, A.

    2015-01-01

    For the production of a polarized antiproton beam various methods have been suggested including the possibility that antiprotons may be produced polarized which will be checked experimentally. The polarization of antiprotons produced under typical conditions for antiproton beam preparation will be measured at the CERN/PS. If the production process creates some polarization a polarized antiproton beam could be prepared by a rather simple modification of the antiproton beam facility. The detection setup and the expected experimental conditions are described.

  12. ASACUSA Anti-protonic Helium_Final

    CERN Document Server

    CERN Audiovisual Production Service; CERN AD; Paola Catapano; Julien Ordan, Arzur Catel; Paola Catapano; ASACUSA COLLABORATION

    2016-01-01

    Latest precision measurement of the mass of the proton and the anti proton though the production of antiprotonic helium by the ASACUSA experiment at CERN's antimatter factory, with a beam from the Antiproton Decelerator

  13. Compression of Antiproton Clouds for Antihydrogen Trapping

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wurtele, J S; Yamazaki, Y

    2008-01-01

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report the first detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile and its relation to that of the electron plasma.

  14. Antiprotonic helium

    CERN Multimedia

    Eades, John

    2005-01-01

    An exotic atom in w hich an electron and an antiproton orbit a helium nucleus could reveal if there are any differences between matter and antimatter. The author describes this unusual mirror on the antiworld (5 pages)

  15. Direct measurement of transition frequencies in isolated pHe+ atoms, and new CPT-violation limits on the antiproton charge and mass.

    Science.gov (United States)

    Hori, M; Eades, J; Hayano, R S; Ishikawa, T; Pirkl, W; Widmann, E; Yamaguchi, H; Torii, H A; Juhász, B; Horváth, D; Yamazaki, T

    2003-09-19

    A radio frequency quadrupole decelerator and achromatic momentum analyzer were used to decelerate antiprotons and produce p4He+ and p3He+ atoms in ultra-low-density targets, where collision-induced shifts of the atomic transition frequencies were negligible. The frequencies at near-vacuo conditions were measured by laser spectroscopy to fractional precisions of (6-19) x 10(-8). By comparing these with QED calculations and the antiproton cyclotron frequency, we set a new limit of 1 x 10(-8) on possible differences between the antiproton and proton charges and masses.

  16. Precision Measurement of the Energies and Line Shapes of Antiprotonic Lyman and Balmer Transitions From Hydrogen and Helium Isotopes

    CERN Multimedia

    2002-01-01

    % PS207 \\\\ \\\\ For the study of the antiproton-proton and antiproton-nuclear spin-spin and spin-orbital interaction at threshold a high resolution measurement is proposed of the line shapes and energy shifts of antiprotonic K$\\alpha$ and L$\\alpha$ transitions of hydrogen and helium isotopes. The intense LEAR beam, stopped in the cyclotron trap at low gas pressure, provides a unique~X-ray~source with sufficient brightness. Charge coupled devices with their excellent background rejection and energy resolution allow a precise determination of the strong shifts and widths of the 1s hyperfine states of protonium, in addition the detection of the $\\bar{p}$D K$\\alpha$ transition should be possible. A focussing crystal spectrometer with a resolution $\\Delta$E/E of about l0$ ^- ^{4} $, which is superior in the accuracy of the energy determination by two orders of magnitude as compared to the present detection methods, will be used to measure the energies of the L$\\alpha$ transitions. This permits a first direct measure...

  17. Precision Measurement of Low-Energy Antiprotons with GAPS for Dark Matter and Primordial Black Hole Physics

    CERN Document Server

    Aramaki, T; von Doetinchem, P; Fuke, H; Hailey, C J; Mognet, S A I; Ong, R A; Perez, K M; Zweerink, J

    2014-01-01

    The general antiparticle spectrometer (GAPS) experiment is an indirect dark matter search focusing on antiparticles produced by WIMP annihilation and decay in the Galactic halo. In addition to the very powerful search channel provided by antideuterons, GAPS has a strong capability to measure low-energy antiprotons (0.07 $\\le$ E $\\le$ 0.25 GeV) as dark matter signatures. This is an especially effective means for probing light dark matter, whose existence has been hinted at in the direct dark matter searches, including the recent result from the CDMS-II experiment. While severely constrained by LUX and other direct dark matter searches, light dark matter candidates are still viable in an isospin- violating dark matter scenario and halo-independent analysis. Along with the excellent antideuteron sensitivity, GAPS will be able to detect an order of magnitude more low-energy antiprotons, compared to BESS and PAMELA, providing a precision measurement of low-energy antiproton flux and a unique channel for probing li...

  18. Measurements of Electron Spectra in the Forward Direction in Slow-Antiproton Carbon-Foil Collisions

    Science.gov (United States)

    Yamazaki, Yasunori; Kuroki, Kenro; Komaki, Ken-Ichiro; Andersen, Lars H.; Horsdal-Pedersen, Erik; Hvelplund, Preben; Knudsen, Helge; M{ø}ller, S{ø}ren P.; Uggerh{ø}j, Erik; Elsener, Konrad

    1990-08-01

    The spectrta of electrons emitted in the forward direction from antiproton and proton bombardments on carbon foils have been studied for projectile energies from 500 to 750 keV. Our main observation is that at the electron energy where the well-known convoy peak is observed for proton impact, the spectrum for equivelocity antiprotons is smooth, showing no indication of a deep anticusp. However, around 50 eV below the electron energy where the cusp is observed for proton impact, we have observed a small peak for antiproton impact. The energy and the relative intensity of the bump are found to be consistent with those predicted for electrons released from a wake-riding state.

  19. Measurement of Cosmic Ray antiproton/proton flux ratio at TeV energies with ARGO-YBJ

    CERN Document Server

    Di Sciascio, G

    2011-01-01

    Cosmic ray antiprotons provide an important probe for the study of cosmic-ray propagation in the interstellar space and to investigate the existence of Galactic dark matter. The ARGO-YBJ experiment, located at the Yangbajing Cosmic Ray Laboratory (Tibet, P.R. China, 4300 m a.s.l., 606 g/cm$^2$), is the only experiment exploiting the full coverage approach at very high altitude presently at work. The ARGO-YBJ experiment is particularly effective in measuring the cosmic ray antimatter content via the observation of the cosmic rays Moon shadowing effect. Based on all the data recorded during the period from July 2006 through November 2009 and a full Monte Carlo simulation, we searched for the existence of the shadow produced by antiprotons at the few-TeV energy region. No evidence of the existence of antiprotons was found in this energy region. Upper limits to the antip/p flux ratio are set to 5 % at a median energy of 2 TeV and 6 % at 5 TeV with a confidence level of 90 %. In the few-TeV energy range this resul...

  20. Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    Science.gov (United States)

    Aguilar, M.; Ali Cavasonza, L.; Alpat, B.; Ambrosi, G.; Arruda, L.; Attig, N.; Aupetit, S.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Başeǧmez-du Pree, S.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bindi, V.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Boschini, M. J.; Bourquin, M.; Bueno, E. F.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Castellini, G.; Cernuda, I.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, G. M.; Chen, H. S.; Cheng, L.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Coste, B.; Creus, W.; Crispoltoni, M.; Cui, Z.; Dai, Y. M.; Delgado, C.; Della Torre, S.; Demirköz, M. B.; Derome, L.; Di Falco, S.; Dimiccoli, F.; Díaz, C.; von Doetinchem, P.; Dong, F.; Donnini, F.; Duranti, M.; D'Urso, D.; Egorov, A.; Eline, A.; Eronen, T.; Feng, J.; Fiandrini, E.; Finch, E.; Fisher, P.; Formato, V.; Galaktionov, Y.; Gallucci, G.; García, B.; García-López, R. J.; Gargiulo, C.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Giovacchini, F.; Goglov, P.; Gómez-Coral, D. M.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guerri, I.; Guo, K. H.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hoffman, J.; Hsieh, T. H.; Huang, H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kang, S. C.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Konak, C.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Li, H. S.; Li, J. Q.; Li, J. Q.; Li, Q.; Li, T. X.; Li, W.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, Hu; Lu, S. Q.; Lu, Y. S.; Luebelsmeyer, K.; Luo, F.; Luo, J. Z.; Lv, S. S.; Majka, R.; Mañá, C.; Marín, J.; Martin, T.; Martínez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Nelson, T.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Pauluzzi, M.; Pensotti, S.; Pereira, R.; Picot-Clemente, N.; Pilo, F.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Putze, A.; Quadrani, L.; Qi, X. M.; Qin, X.; Qu, Z. Y.; Räihä, T.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodríguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Schael, S.; Schmidt, S. M.; Schulz von Dratzig, A.; Schwering, G.; Seo, E. S.; Shan, B. S.; Shi, J. Y.; Siedenburg, T.; Son, D.; Song, J. W.; Sun, W. H.; Tacconi, M.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Türkoǧlu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vázquez Acosta, M.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Vitale, V.; Vitillo, S.; Wang, L. Q.; Wang, N. H.; Wang, Q. L.; Wang, X.; Wang, X. Q.; Wang, Z. X.; Wei, C. C.; Weng, Z. L.; Whitman, K.; Wienkenhöver, J.; Willenbrock, M.; Wu, H.; Wu, X.; Xia, X.; Xiong, R. Q.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Yang, Y.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, C.; Zhang, J.; Zhang, J. H.; Zhang, S. D.; Zhang, S. W.; Zhang, Z.; Zheng, Z. M.; Zhu, Z. Q.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; AMS Collaboration

    2016-08-01

    A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49 ×1 05 antiproton events and 2.42 ×1 09 proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ˜60 to ˜500 GV , the antiproton p ¯, proton p , and positron e+ fluxes are found to have nearly identical rigidity dependence and the electron e- flux exhibits a different rigidity dependence. Below 60 GV, the (p ¯/p ), (p ¯/e+), and (p /e+) flux ratios each reaches a maximum. From ˜60 to ˜500 GV , the (p ¯/p ), (p ¯/e+), and (p /e+) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

  1. Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station.

    Science.gov (United States)

    Aguilar, M; Ali Cavasonza, L; Alpat, B; Ambrosi, G; Arruda, L; Attig, N; Aupetit, S; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Başeǧmez-du Pree, S; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bindi, V; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Boschini, M J; Bourquin, M; Bueno, E F; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, G M; Chen, H S; Cheng, L; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Creus, W; Crispoltoni, M; Cui, Z; Dai, Y M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Dimiccoli, F; Díaz, C; von Doetinchem, P; Dong, F; Donnini, F; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eronen, T; Feng, J; Fiandrini, E; Finch, E; Fisher, P; Formato, V; Galaktionov, Y; Gallucci, G; García, B; García-López, R J; Gargiulo, C; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Giovacchini, F; Goglov, P; Gómez-Coral, D M; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kang, S C; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Konak, C; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H S; Li, J Q; Li, J Q; Li, Q; Li, T X; Li, W; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, Hu; Lu, S Q; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Nelson, T; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Pauluzzi, M; Pensotti, S; Pereira, R; Picot-Clemente, N; Pilo, F; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Putze, A; Quadrani, L; Qi, X M; Qin, X; Qu, Z Y; Räihä, T; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Schael, S; Schmidt, S M; Schulz von Dratzig, A; Schwering, G; Seo, E S; Shan, B S; Shi, J Y; Siedenburg, T; Son, D; Song, J W; Sun, W H; Tacconi, M; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vázquez Acosta, M; Vecchi, M; Velasco, M; Vialle, J P; Vitale, V; Vitillo, S; Wang, L Q; Wang, N H; Wang, Q L; Wang, X; Wang, X Q; Wang, Z X; Wei, C C; Weng, Z L; Whitman, K; Wienkenhöver, J; Willenbrock, M; Wu, H; Wu, X; Xia, X; Xiong, R Q; Xu, W; Yan, Q; Yang, J; Yang, M; Yang, Y; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, C; Zhang, J; Zhang, J H; Zhang, S D; Zhang, S W; Zhang, Z; Zheng, Z M; Zhu, Z Q; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P

    2016-08-26

    A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

  2. ANTIPROTONS PRODUCED IN SUPERNOVA REMNANTS

    Energy Technology Data Exchange (ETDEWEB)

    Berezhko, E. G.; Ksenofontov, L. T., E-mail: ksenofon@ikfia.sbras.ru [Yu. G. Shafer Institute of Cosmophysical Research and Aeronomy, 31 Lenin Avenue, 677891 Yakutsk (Russian Federation)

    2014-08-20

    We present the energy spectrum of an antiproton cosmic ray (CR) component calculated on the basis of the nonlinear kinetic model of CR production in supernova remnants (SNRs). The model includes the reacceleration of antiprotons already existing in the interstellar medium as well as the creation of antiprotons in nuclear collisions of accelerated protons with gas nuclei and their subsequent acceleration by SNR shocks. It is shown that the production of antiprotons in SNRs produces a considerable effect in their resultant energy spectrum, making it essentially flatter above 10 GeV so that the spectrum at TeV energies increases by a factor of 5. The calculated antiproton spectrum is consistent with the PAMELA data, which correspond to energies below 100 GeV. As a consistency check, we have also calculated within the same model the energy spectra of secondary nuclei and show that the measured boron-to-carbon ratio is consistent with the significant SNR contribution.

  3. Measurement of the Antiprotonic Lyman- and Balmer X-rays of $\\overline{p}H$ and $\\overline{p}D$ Atoms at Very Low Target Pressures

    CERN Multimedia

    2002-01-01

    The aim of this experiment is to measure the energies and intensities of the n @A 1 (Lyman) and n @A 2 (Balmer) tansitions with high accuracy in both @*H and @*D, from which the strong interaction effects of the 1s- and 2p-level can be extracted. These observables may be related to the antiproton-proton and antiproton-neutron scattering length. \\\\ \\\\ Since in these targets collisional Stark effect occurs, we will stop the antiprotons in extreme thin gaseous targets (pressure as low as 10 Torr), where no Stark effect occurs and the 2-1 transition is favoured. In order to use antiprotons with high efficiency despite of the low target density, we will trap antiprotons of a momentum of 100 MeV/c in a magnetic field of cyclotron characteristics. The antiprotons are decelerated by their energy loss in the target gas. The focusing properties of the magnetic field serve to compensate the multiple scattering and we will end up with a concentrated stopping distribution at the centre. Due to the long orbiting time, back...

  4. Antiproton Target

    CERN Multimedia

    1980-01-01

    Antiproton target used for the AA (antiproton accumulator). The first type of antiproton production target used from 1980 to 1982 comprised a rod of copper 3mm diameter and 120mm long embedded in a graphite cylinder that was itself pressed into a finned aluminium container. This assembly was air-cooled and it was used in conjunction with the Van der Meer magnetic horn. In 1983 Fermilab provided us with lithium lenses to replace the horn with a view to increasing the antiproton yield by about 30%. These lenses needed a much shorter target made of heavy metal - iridium was chosen for this purpose. The 50 mm iridium rod was housed in an extension to the original finned target container so that it could be brought very close to the entrance to the lithium lens. Picture 1 shows this target assembly and Picture 2 shows it mounted together with the lithium lens. These target containers had a short lifetime due to a combination of beam heating and radiation damage. This led to the design of the water-cooled target in...

  5. The Antiproton Accumulator becomes Antiproton Decelerator

    CERN Multimedia

    1980-01-01

    The photos show the Antiproton Accumulator (AA) transformed into Antiproton Decelerator. The AA was used at CERN between 1981 and 1999 before being replaced by the Antiproton Decelerator (AD). The AA was used to collect and stochastically cool antiprotons used in proton-antiproton collisions in the SPS collider. This lead to the discovery of the W and Z bosons in 1983 and the Nobel Prize for Carlo Rubbia and Simon van der Meer in 1984.

  6. Measurement of the Cosmic-Ray Antiproton Spectrum at Solar Minimum with a Long-Duration Balloon Flight over Antarctica

    Science.gov (United States)

    Abe, K.; Fuke, H.; Haino, S.; Hams, T.; Hasegawa, M.; Horikoshi, A.; Kim, K. C.; Kusumoto, A.; Lee, M. H.; Makida, Y.; Matsuda, S.; Matsukawa, Y.; Mitchell, J. W.; Nishimura, J.; Nozaki, M.; Orito, R.; Ormes, J. F.; Sakai, K.; Sasaki, M.; Seo, E. S.; Shinoda, R.; Streitmatter, R. E.; Suzuki, J.; Tanaka, K.; Thakur, N.

    2012-01-01

    The energy spectrum of cosmic-ray antiprotons (p-bar's) from 0.17 to 3.5 GeV has been measured using 7886 p-bar's detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. This shows good consistency with secondary p-bar calculations. Cosmologically primary p-bar's have been investigated by comparing measured and calculated p-bar spectra. BESS-Polar II data.show no evidence of primary p-bar's from the evaporation of primordial black holes.

  7. Out-of-field dose measurements in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kaderka, Robert

    2011-07-13

    This thesis describes the results from measurements of the out-of-field dose in radiotherapy. The dose outside the treatment volume has been determined in a water phantom and an anthropomorphic phantom. Measurements were performed with linac photons, passively delivered protons, scanned protons, passively delivered carbon ions as well as scanned carbon ions. It was found that the use of charged particles for radiotherapy reduces the out-of-field dose by up to three orders of magnitude compared to conventional radiotherapy with photons.

  8. Coincidence studies with antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2010-02-01

    We present a short overview of a new method for calculating fully differential cross sections that is able to describe any aspect of coincidence measurements involving heavy projectiles. The method is based upon impact parameter close coupling with pseudostates. Examples from antiproton impact ionization are shown.

  9. Measurement of Cosmic-Ray Antiproton Spectrum at Solar Minimum with a Long-Duration Balloon Flight in Antarctica

    Science.gov (United States)

    Abe, K.; Fuke, H.; Haino, S.; Hams, T.; Hasegawa, M.; Horikoshi, A.; Kim, K. C.; Kusumoto, A.; Lee, M. H.; Makida, Y.; Matsuda, S.; Matsukawa, Y.; Mitchell, J. W.; Nishimura, J.; Nozaki, M.; Orito, R.; Ormes, J. F.; Sakai, K.; Sasaki, M.; Seo, E. S.; Shinoda, R.; Streitmatter, R. E.; Suzuki, J.; Tanaka, K.; Thakur, N.

    2011-01-01

    The energy spectrum of cosmic-ray antiprotons (p(raised bar)'s) collected by the BESS-Polar II instrument during a long-duration flight over Antarctica in the solar minimum period of December 2007 through January 2008. The p(raised bar) spectrum measured by BESS-Polar II shows good consistency with secondary p(raised bar) calculations. Cosmologically primary p(raised bar)'s have been searched for by comparing the observed and calculated p(raised bar) spectra. The BESSPolar II result shows no evidence of primary p(raised bar)'s originating from the evaporation of PBH.

  10. Measurements of Wake-Riding Electrons in Antiproton-Carbon-Foil Collisions

    CERN Multimedia

    2002-01-01

    When a charged particle passes through dielectric media, e.g. a thin carbon foil, a ``wake'' is induced. The characteristic wake-potential shows an oscillatory behaviour, with a wavelength of about $ 2 \\pi v _{p} / \\omega _{p} _{l} $ where $ v _{p} $ is the projectile velocity and $ \\omega _{p} _{l} $ the plasmon energy of the target. This induced wake potential is superimposed on the Coulomb potential of the projectile, the latter leading to a pronounced ``cusp'' of electrons leaving the solid at $ v _{e} app v _{p} $ for positively charged projectiles in the MeV region. Correspondingly, an ``anti-cusp'' is expected for antiprotons. \\\\ \\\\ In the solid, the wake-potential leads to an attractive force on electrons, and a dynamic electronic state is predicted both for proton and antiproton projectiles. In the solid, the wake-riding electrons are travelling with the projectile speed $ v _{p} $ Upon exit of the foil, the electron released from the wake-riding state of an antiproton will suddenly find itself in th...

  11. A reservoir trap for antiprotons

    CERN Document Server

    Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

    2015-01-01

    We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

  12. Radiotherapy

    Directory of Open Access Journals (Sweden)

    Rema Jyothirmayi

    1999-01-01

    Full Text Available Purpose. Conservative treatment in the form of limited surgery and post-operative radiotherapy is controversial in hand and foot sarcomas, both due to poor radiation tolerance of the palm and sole, and due to technical difficulties in achieving adequate margins.This paper describes the local control and survival of 41 patients with soft tissue sarcoma of the hand or foot treated with conservative surgery and radiotherapy. The acute and late toxicity of megavoltage radiotherapy to the hand and foot are described. The technical issues and details of treatment delivery are discussed. The factors influencing local control after radiotherapy are analysed.

  13. Antiproton Radiation Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael H.; Petersen, Jørgen B.B.

    2007-01-01

    the radiobiological properties using antiprotons at 50 and 125 MeV from the Antiproton Decelerator (AD) at CERN. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film. Radiobiological experiments were done with Chinese V79 WNRE hamster cells. Monte Carlo particle...... transport codes were investigated and compared with results obtained from the ionization chambers and alanine pellets. A track structure model have been applied on the calculated particle spectrum, and been used to predict the LET-dependent response of the alanine pellets. The particle transport program...... FLUKA produced data which were in excellent agreement with our ionization chamber measurements, and in good agreement with our alanine measurements. FLUKA is now being used to generate a wide range of depth dose data at several energies, including secondary particle–energy spectra, which will be used...

  14. The antiproton depth–dose curve in water

    CERN Document Server

    Bassler, N; Jäkel, O; Knudsen, H V; Kovacevic, S

    2008-01-01

    We have measured the depth–dose curve of 126 MeV antiprotons in a water phantom using ionization chambers. Since the antiproton beam provided by CERN has a pulsed structure and possibly carries a high-LET component from the antiproton annihilation, it is necessary to correct the acquired charge for ion recombination effects. The results are compared with Monte Carlo calculations and were found to be in good agreement. Based on this agreement we calculate the antiproton depth–dose curve for antiprotons and compare it with that for protons and find a doubling of the physical dose in the peak region for antiprotons.

  15. The biological effectiveness of antiproton irradiation

    DEFF Research Database (Denmark)

    Holzscheiter, Michael H.; Bassler, Niels; Agazaryan, Nzhde;

    2006-01-01

    Background and purpose: Antiprotons travel through tissue in a manner similar to that for protons until they reach the end of their range where they annihilate and deposit additional energy. This makes them potentially interesting for radiotherapy. The aim of this study was to conduct the first e...

  16. Physics using cold antiprotons

    Science.gov (United States)

    Hayano, Ryugo S.

    2004-10-01

    Recent progress of low-energy antiproton physics by atomic spectroscopy and collisions using slow antiprotons collaboration at CERN AD is presented. High-precision spectroscopy of antiprotonic helium-a neutral three-body system overlinepe-He2+(=overlinepHe+) produced when antiprotons (overlinep) are stopped in various phases of helium-has tested 3-body QED theories as well as proton-vs-antiproton CPT to within ∼10-8. This was achieved by using a newly-developed radiofrequency quadrupole decelerator. Other ongoing and future experiments using low-energy antiprotons are discussed.

  17. Physics using cold antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Hayano, R.S. E-mail: hayano@phys.s.u-tokyo.ac.jp

    2004-10-11

    Recent progress of low-energy antiproton physics by atomic spectroscopy and collisions using slow antiprotons collaboration at CERN AD is presented. High-precision spectroscopy of antiprotonic helium--a neutral three-body system pbare{sup -}He{sup 2+}(=pbarHe{sup +}) produced when antiprotons (pbar) are stopped in various phases of helium--has tested 3-body QED theories as well as proton-vs-antiproton CPT to within {approx}10{sup -8}. This was achieved by using a newly-developed radiofrequency quadrupole decelerator. Other ongoing and future experiments using low-energy antiprotons are discussed.

  18. The Antiproton Depth-Dose Curve in Water

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael; Jäkel, Oliver

    2008-01-01

    We have measured the depth-dose curve of 126 MeV antiprotons in a water phantom using ionization chambers. Since the antiproton beam provided by CERN has a pulsed structure and possibly carries a high-LET component from the antiproton annihilation, it is necessary to correct the acquired charge...

  19. The low energy atmospheric antiproton albedo

    Science.gov (United States)

    Cole, J. B.; Ormes, J. F.

    1989-01-01

    The flux of albedo antiprotons in the 100-1000 MeV kinetic energy range produced by the cosmic ray primaries in the atmosphere is calculated. It is shown that this is not a significant background to measurements of the low energy anti-proton cosmic ray flux.

  20. Antiproton radiation found effective in cancer research

    CERN Multimedia

    2003-01-01

    "An international collaboration of scientists has completed the first ever antiproton beam experiments designed to reveal the biological effectiveness of antiproton radiation in terminating cells used for cancer research...PBar Labs assembled the collaboration at CERN (European Organization for Nuclear Research in Geneva) to perform the measurements" (1 page).

  1. Antiproton-Decelerator (AD)

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    When the Low-Energy Antiproton Ring (LEAR) was stopped in 1996, because of its costly operation, a cheaper way of continuing low-energy antiproton physics was sought. The Antiproton-Collector (AC), added in 1987 to the Antiproton Accumulator (AA) to provide a tenfold intensity increase, was converted into the Antiproton-Decelerator (AD). Antiprotons from the target at 3.5 GeV/c are decelerated to 100 MeV/c, and fast-ejected to the experiments. Major changes were necessary. Above all, the conversion from a constant-field machine to one with a magnetic cycle, modulating the field by an impressive factor 35. New systems for stochastic and electron cooling had to be added. Beam diagnostics at an intensity of only 2E7 antiprotons was a challenge. In 2000, the AD began delivery of antiprotons to the experiments.

  2. Antiproton Accumulator (AA)

    CERN Multimedia

    Photographic Service

    1980-01-01

    The AA in its final stage of construction, before it disappeared from view under concrete shielding. Antiprotons were first injected, stochastically cooled and accumulated in July 1980. From 1981 on, the AA provided antiprotons for collisions with protons, first in the ISR, then in the SPS Collider. From 1983 on, it also sent antiprotons, via the PS, to the Low-Energy Antiproton Ring (LEAR). The AA was dismantled in 1997 and shipped to Japan.

  3. Testing Quantum Chromodynamics with Antiprotons

    CERN Document Server

    Brodsky, S J

    2004-01-01

    The antiproton storage ring HESR to be constructed at GSI will open up a new range of perturbative and nonperturbative tests of QCD in exclusive and inclusive reactions. I discuss 21 tests of QCD using antiproton beams which can illuminate novel features of QCD. The proposed experiments include the formation of exotic hadrons, measurements of timelike generalized parton distributions, the production of charm at threshold, transversity measurements in Drell-Yan reactions, and searches for single-spin asymmetries. The interactions of antiprotons in nuclear targets will allow tests of exotic nuclear phenomena such as color transparency, hidden color, reduced nuclear amplitudes, and the non-universality of nuclear antishadowing. The AdS/CFT correspondence of large $N_C$ supergravity theory in higher-dimensional anti-de Sitter space with supersymmetric QCD in 4-dimensional space-time has important implications for hadron phenomenology in the conformal limit, including the nonperturbative derivation of counting rul...

  4. Antiprotons get biological

    CERN Multimedia

    2003-01-01

    After its final run in September, the first results of the Antiproton Cell Experiment (ACE) look very promising. It was the first experiment to take data on the biological effects of antiproton beams to evaluate the potential of antiprotons in radiation therapy.

  5. Experiments on Antiprotons: Antiproton-Nucleon Cross Sections

    Science.gov (United States)

    Chamberlain, Owen; Keller, Donald V.; Mermond, Ronald; Segre, Emilio; Steiner, Herbert M.; Ypsilantis, Tom

    1957-07-22

    In this paper experiments are reported on annihilation and scattering of antiprotons in H{sub 2}O , D{sub 2}O, and O{sub 2}. From the data measured it is possible to obtain an antiproton-proton and an antiproton-deuteron cross section at 457 Mev (lab). Further analysis gives the p-p and p-n cross sections as 104 mb for the p-p reaction cross section and 113 mb for the p-n reaction cross section. The respective annihilation cross sections are 89 and 74 mb. The Glauber correction necessary in order to pass from the p-d to the p-n cross section by subtraction of the p-p cross section is unfortunately large and somewhat uncertain. The data are compared with the p-p and p-n cross sections and with other results on p-p collisions.

  6. antiproton focusing horn

    CERN Multimedia

    1980-01-01

    Was used for the AA (antiproton accumulator). Making an antiproton beam took a lot of time and effort. Firstly, protons were accelerated to an energy of 26 GeV in the PS and ejected onto a metal target. From the spray of emerging particles, a magnetic horn picked out 3.6 GeV antiprotons for injection into the AA through a wide-aperture focusing quadrupole magnet. For a million protons hitting the target, just one antiproton was captured, 'cooled' and accumulated. It took 3 days to make a beam of 3 x 10^11 - three hundred thousand million - antiprotons.

  7. Antiproton Focus Horn

    CERN Multimedia

    1974-01-01

    Was used for the AA (antiproton accumulator). Making an antiproton beam took a lot of time and effort. Firstly, protons were accelerated to an energy of 26 GeV in the PS and ejected onto a metal target. From the spray of emerging particles, a magnetic horn picked out 3.6 GeV antiprotons for injection into the AA through a wide-aperture focusing quadrupole magnet.For a million protons hitting the target, just one antiproton was captured, 'cooled' and accumulated. It took 3 days to make a beam of 3 x 10^11 -, three hundred thousand million - antiprotons.

  8. Cosmic ray antiproton measurements in the 4-19 GeV energy range using the NMSU/WiZard-matter antimatter superconducting spectrometer 2 (MASS2)

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G.; Bongiorno, F. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Brunetti, M.T.; Codini, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy)]|[INFN, Rome (Italy); Hof, M. [Siegen Univ. (Germany). Fachbereich Physik; Golden, R.L.; Stochaj, S.J. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.M. [Florence Univ. (Italy)]|[INFN, Florence (Italy)

    1995-09-01

    The p/p-ratio from 4 to 19 GeV has been measured using the NMSU/WiZard balloon borne matter antimatter superconducting spectrometer (MASS2) instrument. This is the first confirmation of the cosmic ray antiproton component made in this energy range since their discovery in 1979. The MASS2 instrument is an updated version of the instrument flown in 1979. The p/p- ratio is 1.52x10{sup -}4.

  9. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Maglieri, Robert, E-mail: robert.maglieri@mail.mcgill.ca; Evans, Michael; Seuntjens, Jan; Kildea, John [Medical Physics Unit, McGill University, Montreal, Quebec H4A 3J1 (Canada); Licea, Angel [Canadian Nuclear Safety Commission, Ottawa, Ontario K1P 5S9 (Canada)

    2015-11-15

    Purpose: Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. Methods: The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation–maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. Results: The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors’ measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. Conclusions: The NNS may

  10. High-precision spectroscopy of antiprotonic helium

    CERN Document Server

    Widmann, E

    2001-01-01

    We present first results of laser and microwave spectroscopy experiments of antiprotonic helium performed at the new Antiproton Decelerator (AD) at CERN. Extending a series of previous measurements done at the Low Energy Antiproton Ring (LEAR) of CERN, several laser- induced transitions of the antiproton in the exotic three-body system He/sup 2+/-e/sup -/-p could be determined with a precision down to 1.3*10/sup -7/. This constitutes an improvement of a factor 3 over previous measurements, and allows to test accurate three-body calculations of this system that include QED corrections. The observed agreement on the same level can be used to infer CPT limits on the antiproton charge and mass. Furthermore, a first indication of a resonance signal of a two-laser microwave triple experiment to measure the hyperfine splitting of antiprotonic helium could been observed. Such a measurement has the potential to determine the antiproton magnetic moment to a higher precision that it is known today. (19 refs).

  11. Measurement of electroweak single top quark production in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Peter Joseph [Univ. of California, Los Angeles, CA (United States)

    2008-01-01

    The top quark is an extremely massive fundamental particle that is predominantly produced in pairs at particle collider experiments. The Standard Model of particle physics predicts that top quarks can also be produced singly by the electroweak force; however, this process is more difficult to detect because it occurs at a smaller rate and is more difficult to distinguish from background processes. The cross section of this process is related to the Cabbibo-Kobayashi-Maskawa matrix element |V tb|, and measurement of the single top quark production cross section is currently the only method to directly measure this quantity without assuming the number of generations of fermions. This thesis describes a measurement of the cross section of electroweak single top quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. This analysis uses 2.2 fb-1 of integrated luminosity recorded by the Collider Detector at Fermilab. The search is performed using a matrix element method which calculates the differential cross section for each event for several signal and background hypotheses. These numbers are combined into a single discriminant and used to construct templates from Monte Carlo simulation. A maximum likelihood fit to the data distribution gives a measurement of the cross section. This analysis measures a value of 2.2$+0.8\\atop{-0.7}$ pb, which corresponds to a value of |V tb| = 0.88$+0.16\\atop{-0.14}$experimental±0.7(theoretical). The probability that this result originates from a background fluctuation in the absence of single top production (p-value) is 0.0003, which is equivalent to 3.4 standard deviations in Gaussian statistics. The expected (median) p-value as estimated from pseudo-experiments for this analysis is 0.000003, which corresponds to 4.5 standard deviations in Gaussian statistics.

  12. Physics with thermal antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Hynes, M.V.; Campbell, L.J.

    1988-01-01

    The same beam cooling techniques that have allowed for high luminosity antiproton experiments at high energy also provide the opportunity for experiments at ultra-low energy. Through a series of deceleration stages, antiprotons collected and cooled at the peak momentum for production can by made available at thermal or sub-thermal energies. In particular, the CERN, PS-200 collaboration is developing an RFO-plused ion trap beam line for the antiproton gravitational mass experiment at LEAR that will provide beams of antiprotons in the energy range 0.001--1000.0 eV. Antiprotons at these energies make these fundamentals particles available for experiments in condensed matter and atomic physics. The recent speculation that antiprotons may form metastable states in some forms of normal matter could open many new avenues of basic and applied research. 7 refs., 3 figs.

  13. ASACUSA hits antiproton jackpot

    CERN Multimedia

    2001-01-01

    The Japanese-European ASACUSA collaboration, which takes its name from the oldest district of Tokyo, approaches the antimatter enigma in a different way from the other two AD experiments, by inserting antiprotons into ordinary atoms. Last month the collaboration succeeded in trapping about a million antiprotons. The ASACUSA antiproton trap (lower cylinder), surmounted by its liquid helium reservoir. Looking on are Ken Yoshiki-Franzen, Zhigang Wang, Takahito Tasaki, Suzanne Reed, John Eades, Masaki Hori, Yasunori Yamazaki, Naofumi Kuroda, Jun Sakaguchi, Berti Juhasz, Eberhard Widmann and Ryu Hayano. A key element of the ASACUSA apparatus is its decelerating Radiofrequency Quadrupole magnet, RFQD. After tests with protons in Aarhus, this was installed in ASACUSA's antiproton beam last October (Bulletin 41/2000, 9 October 2000). Constructed by Werner Pirkl's group in PS Division, the RFQD works by applying an electric field to the AD antiproton pulse the opposite direction to its motion. As the antiprotons slo...

  14. Physics at CERN's Antiproton Decelerator

    CERN Document Server

    Hori, M

    2013-01-01

    The Antiproton Decelerator of CERN began operation in 1999 to serve experiments for studies of CPT invariance by precision laser and microwave spectroscopy of antihydrogen ($\\bar{\\rm H}$) and antiprotonic helium ($\\bar{p}{\\rm He}^+$). The first 12 years of operation saw cold $\\bar{\\rm H}$ synthesized by overlapping clouds of positrons ($e^+$) and antiprotons ($\\bar{p}$) confined in magnetic Penning traps. Cold $\\bar{\\rm H}$ was also produced in collisions between Rydberg positronium atoms and $\\bar{p}$. Ground-state $\\bar{\\rm H}$ was later trapped for up to $\\sim 1000$ s in a magnetic bottle trap, and microwave transitions excited between its hyperfine levels. In the $\\bar{p}{\\rm He}^+$ atom, UV transitions were measured to a precision of (2.3-5) $\\times$ $10^{-9}$ by sub-Doppler two-photon laser spectroscopy. From this the antiproton-to-electron mass ratio was determined as $M_{\\bar{p}}/m_e=$1836.1526736(23), which agrees with the p value. Microwave spectroscopy of $\\bar{p}{\\rm He}^+$ yielded a measurement o...

  15. The anti-proton charge radius

    CERN Document Server

    Crivelli, P; Heiss, M W

    2016-01-01

    The upcoming operation of the Extra Low ENergy Antiprotons (ELENA) ring at CERN, the upgrade of the anti-proton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of $10^{8}$ e$^+$/s will open the possibility for new experiments with anti-hydrogen ($\\bar{\\text{H}}$). Here we propose a scheme to measure the Lamb shift of $\\bar{\\text{H}}$. For a month of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of CPT and the first determination of the anti-proton charge radius at the level of 10%.

  16. Comparison of Optimized Single and Multifield Irradiation Plans of Antiproton, Proton and Carbon Ion Beams

    DEFF Research Database (Denmark)

    Bassler, Niels; Kantemiris, Ioannis; Karaiskos, Pantelis;

    2010-01-01

    Antiprotons have been suggested as a possibly superior modality for radiotherapy, due to the energy released when antiprotons annihilate, which enhances the Bragg peak and introduces a high-LET component to the dose. However, concerns are expressed about the inferior lateral dose distribution...

  17. Prospects for Antiproton Experiments at Fermilab

    CERN Document Server

    Kaplan, Daniel M

    2011-01-01

    Fermilab operates the world's most intense antiproton source. Newly proposed experiments can use those antiprotons either parasitically during Tevatron Collider running or after the end of the Tevatron Collider program. For example, the annihilation of 5 to 8 GeV antiprotons is expected to yield world-leading sensitivities to hyperon rare decays and CP violation. It could also provide the world's most intense source of tagged D^0 mesons, and thus the best near-term opportunity to study charm mixing and, via CP violation, to search for new physics. Other measurements that could be made include properties of the X(3872) and the charmonium system. An experiment using a Penning trap and an atom interferometer could make the world's most precise measurement of the gravitational force on antimatter. These and other potential measurements using antiprotons offer a great opportunity for a broad and exciting physics program at Fermilab in the post-Tevatron era.

  18. LEAR: antiproton extraction lines

    CERN Multimedia

    Photographic Service

    1992-01-01

    Antiprotons, decelerated in LEAR to a momentum of 100 MeV/c (kinetic energy of 5.3 MeV), were delivered to the experiments in an "Ultra-Slow Extraction", dispensing some 1E9 antiprotons over times counted in hours. Beam-splitters and a multitude of beam-lines allowed several users to be supplied simultaneously.

  19. The Antiproton Decelerator

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    A technician works on the Antiproton Decelerator (AD) ring. This machine slows down antiprotons so that they can combine with anti-electrons (positrons) and produce anti-hydrogen. Experiments are set up on the AD to attempt to store antihydrogen and investigate properties of anti-hydrogen, such as its mass.

  20. Measurement of the single top production cross section in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanasijczuk, Andres Jorge [Univ. of Buenos Aires (Argentina)

    2010-03-25

    This thesis describes a search for singly produced top quarks via an electroweak vertex in head-on proton-antiproton collisions at a center of mass energy of √s = 1.96 TeV. The analysis uses a total of 2.3 fb-1 of data collected with the D0 detector at Fermilab, corresponding to two different run periods of the Tevatron collider. Two channels contribute to single top quark production at the Tevatron, the s-channel and the t-channel. In the s-channel, a virtual W boson is produced from the aniquilation of a quark and an antiquark and a top and a bottom quarks are produced from the W decay. The top quark decays almost exclusively into a W boson and a bottom quark. Final states are considered in which the W boson decays leptonically into an electron or a muon plus a neutrino. Thus, at the detector level, the final state characterizing the s-channel contains one lepton, missing energy accounting for the neutrino, and two jets from the two bottom quarks. In the t-channel, the final state has an additional jet coming from a light quark. Clearly, a precise reconstruction of the events requires a precise measurement of the energy of the jets. A multivariate technique, Bayesian neural networks, is used to extract the single top signal from the overwhelming background still left after event selection. A Bayesian likelihood probability is then computed to measure the single top cross section. Assuming the observed excess is due to single top events, the measured single top quark production cross section is σ(p$\\bar{p}$ → tb + X, tqb + X) = 4.70+1.18-0.93 pb. The observed excess is associated with a p-value of (3.2 ± 2.3) x 10-8, assuming the background-only hypothesis. This p-value corresponds to an excess over background of 5.4 standard deviations for a Gaussian density. The p-value computed using the standard model signal cross section of 3.46 pb is (22.7 ± 0.6) x 10-6, corresponding to an expected significance

  1. A Combined Interpretation of CR Nuclei and Antiproton High Energy Measurements

    CERN Document Server

    Evoli, C; Grasso, D; Maccione, L

    2009-01-01

    In the last months several ballon and satellite experiments improved significantly our knowledge of cosmic rays (CR) spectra at high energy. In particular CREAM allowed to measure B/C, C/O and N/O up to 1 TeV and PAMELA the anti-p/p ratio up to 100 GeV with unprecedented accuracy. These measurements offer a valuable probe of CR propagation properties. We performed a statistical analysis to test the compatibility of these results, as well as other most significant experimental data, with the predictions of a new numerical CR diffusion package (DRAGON). We found that above 1 GeV all data are consistent with a diffusion scenario in a well defined range of values of the diffusion coefficient energy power index and normalization.

  2. Measurement of the dijet transverse thrust distribution in proton - anti-proton collisions

    Energy Technology Data Exchange (ETDEWEB)

    Sorin, Maria Veronica

    2003-01-01

    This dissertation presents the first measurement in a hadron collider of an event shape variable, the Dijet Transverse Thrust T$t\\atop{2}$ which is sensitive to the spatial jet distribution on the plane perpendicular to the colliding p$\\bar{p}$ beams. $t\\atop{2}$ is calculated with the two most energetic jets reconstructed with the k$\\perp$ algorithm, and it ranges from T$t\\atop{2}$ =1, for a pencil-like configuration, to T$t\\atop{2}$ =√2/2, for two equal energy jets at 90°. The measurement is based on 87.3 pb-1 of data collected with the D0 detector at the Fermilab Tevatron p$\\bar{p}$ Collider. The cross section is reported as a function of 1-T$t\\atop{2}$ and log (1-T$t\\atop{2}$), with enhances the high statistics T$t\\atop{2}$→1 region, and presented for four separate event energy ranges. The measurement is in good agreement with a fixed-order O(α$3\\atop{s}$) perturbative QCD prediction, except at high T$t\\atop{2}$, where resummation corrections are expected to be important, and below T$t\\atop{2}$≃√3/2, where the leading order diagrams contributing to T$t\\atop{2}$ are O(α$4\\atop{s}$). The data also show a very good level of agreement with a recent Next-to-Leading pQCD three jet generator which covers the full T$t\\atop{2}$ range, except for the T$t\\atop{2}$=1 point.

  3. Antiproton Induced Fission and Fragmentation of Nuclei

    CERN Multimedia

    2002-01-01

    The annihilation of slow antiprotons with nuclei results in a large highly localized energy deposition primarily on the nuclear surface. \\\\ \\\\ The study of antiproton induced fission and fragmentation processes is expected to yield new information on special nuclear matter states, unexplored fission modes, multifragmentation of nuclei, and intranuclear cascades.\\\\ \\\\ In order to investigate the antiproton-nucleus interaction and the processes following the antiproton annihilation at the nucleus, we propose the following experiments: \\item A)~Measurement of several fragments from fission and from multifragmentation in coincidence with particle spectra, especially neutrons and kaons. \\item B)~Precise spectra of $\\pi$, K, n, p, d and t with time-of-flight techniques. \\item C)~Installation of the Berlin 4$\\pi$ neutron detector with a 4$\\pi$ Si detector placed inside for fragments and charged particles. This yields neutron multiplicity distributions and consequently distributions of thermal excitation energies and...

  4. Beam position pickup for antiprotons to the ISR

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    The Antiproton Project, launched for proton-antiproton collisions in the SPS (SPS collider), had a side-line for p-pbar collisions in the ISR. A new transfer line, TT6, was constructed to transport antiprotons from the 26 GeV PS to the injection line TT1 of ISR ring 2. Antiprotons were a scarce commodity. For setting up the lines, beam diagnostic devices in the antiproton path had to work reliably and precisely with just a few low-intensity pilot pules: single bunches of about 2x10**9 antiprotons every few hours. Electrostatic pickup electrodes were used to measure beam position. They could be mounted for measurement in the horizontal plane, as in this picture, or at 90 deg, for the vertical plane.

  5. Measurements of the Ratio Between Double and Single Ionization of Helium for Antiprotons

    CERN Multimedia

    2002-01-01

    The inclusive spectra of @p|0's and @h's associated with @*p annihilation at rest are measured. Peaks in these spectra can be identified either with so far not explicitly observed two mesonic final states such as @p|0@w, @p|0@h, @h@h or @p|0@g, or with production of exotic mesonlike states such as baryonium. The apparatus is also suitable for searching for baryonium through some of its particular decay channels. As a by-product we expect information on direct @g production in @*p annihilations at rest.\\\\ \\\\ The apparatus consists of two modular BGO spectrometers and one array of leadglas detectors. The BGO spectrometers are adjustable in angle relative to each other and to the leadglas matrix, thus allowing to cover an angular range from 9|0 to 180|0, corresponding to momenta of zero to more than 1~GeV/c. The apparatus is designed such as to utilize the full potential of LEAR.

  6. Measurement of proton-proton and proton-antiproton elastic scattering at the European center for nuclear research intersecting storage rings

    CERN Document Server

    Amos, Norman A

    1985-01-01

    Proton-proton and proton-antiproton elastic scattering was measured at the CERN Intersecting Storage Rings. Using the optical theorem, we have extracted the total nuclear cross sections for these collisions. By measuring the interference between the Coulomb amplitude and the nuclear amplitude we have found rho, the ratio of the real part to the imaginary part of the forward nuclear elastic scattering amplitude. Further, we have extracted the nuclear slope parameter in the forward direction. For proton-proton interactions, the total nuclear cross sections measured were 39.95 +- 0.30 mb and 42.19 +- 0.19 mb for center-of-mass energies √s = 30.6 GeV and 52.8 GeV, respectively. The measured values of rho were 0.035 +- 0.009 and 0.071 +- 0.010. For proton-antiproton interactions, the cross sections found were 41.10 +- 0.40 mb and 43.34 +- 0.43 mb, respectively, and the rho values were 0.088 +- 0.025 and 0.066 +- 0.022

  7. Sub-ppm laser spectroscopy of antiprotonic helium and a CPT-violation limit on the antiprotonic charge and mass.

    Science.gov (United States)

    Hori, M; Eades, J; Hayano, R S; Ishikawa, T; Sakaguchi, J; Widmann, E; Yamaguchi, H; Torii, H A; Juhász, B; Horváth, D; Yamazaki, T

    2001-08-27

    Six laser-resonant transitions have been detected in metastable antiprotonic helium atoms produced at the CERN Antiproton Decelerator. They include UV transitions from the last metastable states in the v = n-l-1 = 0 and 1 cascades. Zero-density frequencies were obtained from measured pressure shifts with fractional precisions between 1.3 x 10(-7) and 1.6 x 10(-6). By comparing these with QED calculations and the antiproton cyclotron frequency, we deduce that the antiproton and proton charges and masses agree to within 6 x 10(-8) with a confidence level of 90%.

  8. Measurement of the cosmic ray antiproton/proton flux ratio at TeV energies with the ARGO-YBJ detector

    CERN Document Server

    ,

    2012-01-01

    Cosmic ray antiprotons provide an important probe to study the cosmic ray propagation in the interstellar space and to investigate the existence of dark matter. Acting the Earth-Moon system as a magnetic spectrometer, paths of primary antiprotons are deflected in the opposite sense with respect to those of the protons in their way to the Earth. This effect allows, in principle, the search for antiparticles in the direction opposite to the observed deficit of cosmic rays due to the Moon (the so-called `Moon shadow'). The ARGO-YBJ experiment, located at the Yangbajing Cosmic Ray Laboratory (Tibet, P.R. China, 4300 m a.s.l., 606 g/cm$^2$), is particularly effective in measuring the cosmic ray antimatter content via the observation of the cosmic rays shadowing effect due to: (1) good angular resolution, pointing accuracy and long-term stability; (2) low energy threshold; (3) real sensitivity to the geomagnetic field. Based on all the data recorded during the period from July 2006 through November 2009 and on a fu...

  9. Measurement of the forward-backward asymmetry in low-mass bottom-quark pairs produced in proton-antiproton collisions

    Science.gov (United States)

    Aaltonen, T.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Auerbach, B.; Aurisano, A.; Azfar, F.; Badgett, W.; Bae, T.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauce, M.; Bedeschi, F.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Bland, K. R.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brigliadori, L.; Bromberg, C.; Brucken, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Bussey, P.; Butti, P.; Buzatu, A.; Calamba, A.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cerri, A.; Cerrito, L.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Chokheli, D.; Clark, A.; Clarke, C.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; d'Ascenzo, N.; Datta, M.; de Barbaro, P.; Demortier, L.; Deninno, M.; D'Errico, M.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Dittmann, J. R.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Ebina, K.; Edgar, R.; Erbacher, R.; Errede, S.; Esham, B.; Farrington, S.; Fernández Ramos, J. P.; Field, R.; Flanagan, G.; Forrest, R.; Franklin, M.; Freeman, J. C.; Frisch, H.; Funakoshi, Y.; Galloni, C.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Giokaris, N.; Giromini, P.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grosso-Pilcher, C.; Guimaraes da Costa, J.; Hahn, S. R.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, M.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hays, C.; Heinrich, J.; Herndon, M.; Hocker, A.; Hong, Z.; Hopkins, W.; Hou, S.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Kasmi, A.; Kato, Y.; Ketchum, W.; Keung, J.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. H.; Kim, S. B.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kurata, M.; Laasanen, A. T.; Lammel, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lee, H. S.; Lee, J. S.; Leo, S.; Leone, S.; Lewis, J. D.; Limosani, A.; Lipeles, E.; Lister, A.; Liu, Q.; Liu, T.; Lockwitz, S.; Loginov, A.; Lucchesi, D.; Lucà, A.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lys, J.; Lysak, R.; Madrak, R.; Maestro, P.; Majersky, O.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Marchese, L.; Margaroli, F.; Marino, P.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Mesropian, C.; Miao, T.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakano, I.; Napier, A.; Nett, J.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Okusawa, T.; Orava, R.; Ortolan, L.; Pagliarone, C.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parker, W.; Pauletta, G.; Paulini, M.; Paus, C.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pondrom, L.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ristori, L.; Robson, A.; Rodriguez, T.; Rolli, S.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sakumoto, W. K.; Sakurai, Y.; Santi, L.; Sato, K.; Saveliev, V.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, E. E.; Schwarz, T.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Semenov, A.; Sforza, F.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simonenko, A.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Song, H.; Sorin, V.; St. Denis, R.; Stancari, M.; Stentz, D.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Ukegawa, F.; Uozumi, S.; Vázquez, F.; Velev, G.; Vellidis, C.; Vernieri, C.; Vidal, M.; Vilar, R.; Vizán, J.; Vogel, M.; Volpi, G.; Wagner, P.; Wallny, R.; Wang, S. M.; Waters, D.; Wester, W. C.; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, H.; Wright, T.; Wu, X.; Wu, Z.; Yamamoto, K.; Yamato, D.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Zanetti, A. M.; Zeng, Y.; Zhou, C.; Zucchelli, S.; CDF Collaboration

    2016-06-01

    We report a measurement of the forward-backward asymmetry, AFB , in b b ¯ pairs produced in proton-antiproton collisions and identified by muons from semileptonic b -hadron decays. The event sample is collected at a center-of-mass energy of √{s }=1.96 TeV with the CDF II detector and corresponds to 6.9 fb-1 of integrated luminosity. We obtain an integrated asymmetry of AFB(b b ¯ ) =(1.2 ±0.7 )% at the particle level for b -quark pairs with invariant mass, mb b ¯ , down to 40 GeV /c2 and measure the dependence of AFB(b b ¯ ) on mb b ¯ . The results are compatible with expectations from the standard model.

  10. Measurement of the Two-Jet Differential Cross Section in proton-antiproton Collisions at $\\sqrt{s}$ = 1800 GeV

    CERN Document Server

    Affolder, T; Akopian, A M; Albrow, Michael G; Amaral, P; Amendolia, S R; Amidei, D; Anikeev, K; Antos, J; Apollinari, G; Arisawa, T; Asakawa, T; Ashmanskas, W J; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bailey, M W; Bailey, S; De Barbaro, P; Barbaro-Galtieri, A; Barnes, Virgil E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Belforte, S; Bell, W H; Bellettini, Giorgio; Bellinger, J; Benjamin, D; Bensinger, J; Beretvas, A; Bergé, J P; Berryhill, J W; Bevensee, B; Bhatti, A A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C A; Bloom, K; Blumenfeld, B; Blusk, S R; Bocci, A; Bodek, Arie; Bokhari, W; Bölla, G; Bonushkin, Yu; Bortoletto, Daniela; Boudreau, J; Brandl, A; van den Brink, S C; Bromberg, C; Brozovic, M; Bruner, N L; Buckley-Geer, E; Budagov, Yu A; Budd, H S; Burkett, K; Busetto, G; Byon-Wagner, A; Byrum, K L; Calafiura, P; Campbell, M; Carithers, W C; Carlson, J; Carlsmith, D; Caskey, W; Cassada, J A; Castro, A; Cauz, D; Cerri, A; Chan, A W; Chang, P S; Chang, P T; Chapman, J; Chen, C; Chen, Y C; Cheng, M T; Chertok, M; Chiarelli, G; Chirikov-Zorin, I E; Chlachidze, G; Chlebana, F S; Christofek, L S; Chu, M L; Chung, Y S; Ciobanu, C I; Clark, A G; Connolly, A; Conway, J; Cordelli, M; Cranshaw, J; Cronin-Hennessy, D; Cropp, R; Culbertson, R J; Dagenhart, D; D'Auria, S; De Jongh, F; Dell'Agnello, S; Dell'Orso, Mauro; Demortier, L; Deninno, M M; Derwent, P F; Devlin, T; Dittmann, J R; Donati, S; Done, J; Dorigo, T; Eddy, N; Einsweiler, Kevin F; Elias, J E; Engels, E; Erbacher, R D; Errede, D; Errede, S; Fan, Q; Feild, R G; Fernández, J P; Ferretti, C; Field, R D; Fiori, I; Flaugher, B L; Foster, G W; Franklin, M; Freeman, J; Friedman, J; Fukui, Y; Furic, I K; Galeotti, S; Gallinaro, M; Gao, T; García-Sciveres, M; Garfinkel, A F; Gatti, P; Gay, C; Gerdes, D W; Giannetti, P; Giromini, P; Glagolev, V; Glenzinski, D A; Gold, M; Goldstein, J; Gordon, A; Gorelov, I V; Goshaw, A T; Gotra, Yu; Goulianos, K; Green, C; Grim, G P; Gris, P; Groer, L S; Grosso-Pilcher, C; Günther, M; Guillian, G; Guimarães da Costa, J; Haas, R M; Haber, C; Hafen, E S; Hahn, S R; Hall, C; Handa, T; Handler, R; Hao, W; Happacher, F; Hara, K; Hardman, A D; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Heinrich, J; Heiss, A; Herndon, M; Hill, C; Hoffman, K D; Holck, C; Hollebeek, R J; Holloway, L E; Hughes, R; Huston, J; Huth, J E; Ikeda, H; Incandela, J R; Introzzi, G; Iwai, J; Iwata, Y; James, E; Jensen, H; Jones, M; Joshi, U; Kambara, H; Kamon, T; Kaneko, T; Karr, K M; Kasha, H; Kato, Y; Keaffaber, T A; Kelley, K; Kelly, M; Kennedy, R D; Kephart, R D; Khazins, D M; Kikuchi, T; Kilminster, B; Kim, B J; Kim, D H; Kim, H S; Kim, M J; Kim, S H; Kim, Y K; Kirby, M; Kirk, M; Kirsch, L; Klimenko, S; Koehn, P; Köngeter, A; Kondo, K; Konigsberg, J; Kordas, K; Korn, A J; Korytov, A V; Kovács, E; Kroll, J; Kruse, M; Kuhlmann, S E; Kurino, K; Kuwabara, T; Laasanen, A T; Lai, N; Lami, S; Lammel, S; Lamoureux, J I; Lancaster, J; Lancaster, M; Lander, R; Latino, G; LeCompte, T J; Lee, A M; Lee, K; Leone, S; Lewis, J D; Lindgren, M; Liss, T M; Liu, J B; Liu, Y C; Litvintsev, D O; Lobban, O; Lockyer, N; Loken, J G; Loreti, M; Lucchesi, D; Lukens, P; Lusin, S; Lyons, L; Lys, J; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Mangano, Michelangelo L; Mariotti, M; Martignon, G; Martin, A; Matthews, J A J; Mayer, J; Mazzanti, P; McFarland, K S; McIntyre, P; McKigney, E A; Menguzzato, M; Menzione, A; Mesropian, C; Meyer, A; Miao, T; Miller, R; Miller, J S; Minato, H; Miscetti, S; Mishina, M; Mitselmakher, G; Moggi, N; Moore, E; Moore, R; Morita, Y; Moulik, T; Mulhearn, M; Mukherjee, A; Müller, T; Munar, A; Murat, P; Murgia, S; Nachtman, J; Nagaslaev, V; Nahn, S; Nakada, H; Nakaya, T; Nakano, I; Nelson, C; Nelson, T; Neu, C; Neuberger, D; Newman-Holmes, C; Ngan, C Y P; Niu, H; Nodulman, L; Nomerotski, A; Oh, S H; Ohmoto, T; Ohsugi, T; Oishi, R; Okusawa, T; Olsen, J; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Pappas, S P; Partos, D S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pescara, L; Phillips, T J; Piacentino, G; Pitts, K T; Pompos, A; Pondrom, L; Pope, G; Popovic, M; Prokoshin, F; Proudfoot, J; Ptohos, F; Pukhov, O; Punzi, G; Ragan, K; Rakitine, A; Reher, D; Reichold, A; Ribon, A; Riegler, W; Rimondi, F; Ristori, L; Riveline, M; Robertson, W J; Robinson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Roy, A; Safonov, A; Saint-Denis, R; Sakumoto, W K; Saltzberg, D; Sánchez, C; Sansoni, A; Santi, L; Sato, H; Savard, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scott, A; Scribano, A; Segler, S L; Seidel, S; Seiya, Y; Semenov, A A; Semeria, F; Shah, T; Shapiro, M D; Shepard, P F; Shibayama, T; Shimojima, M; Shochet, M J; Siegrist, J L; Sill, A F; Sinervo, P K; Singh, P; Slaughter, A J; Sliwa, K; Smith, C; Snider, F D; Solodsky, A; Spalding, J; Speer, T; Sphicas, Paris; Spinella, F; Spiropulu, M; Spiegel, L; Steele, J; Stefanini, A; Strologas, J; Strumia, F; Stuart, D; Sumorok, K; Suzuki, T; Takano, T; Takashima, R; Takikawa, K; Tamburello, P D; Tanaka, M; Tannenbaum, B; Taylor, W; Tecchio, M; Tesarek, R J; Teng, P K; Terashi, K; Tether, S; Thompson, A S; Thurman-Keup, R M; Tipton, P; Tkaczyk, S M; Tollefson, K; Tollestrup, Alvin V; Toyoda, H; Trischuk, W; De Trocóniz, J F; Tseng, J; Turini, N; Ukegawa, F; Vaiciulis, T; Valls, J; Vejcik, S; Velev, G V; Vidal, R; Vilar, R; Volobuev, I P; Vucinic, D; Wagner, R G; Wagner, R L; Wahl, J; Wallace, N B; Walsh, A M; Wang, C; Wang, M J; Watanabe, T; Waters, D; Watts, T; Webb, R; Wenzel, H; Wester, W C; Wicklund, A B; Wicklund, E; Wilkes, T; Williams, H H; Wilson, P; Winer, B L; Winn, D; Wolbers, S; Wolinski, D; Wolinski, J; Wolinski, S; Worm, S; Wu, X; Wyss, J; Yagil, A; Yao, W; Yeh, G P; Yeh, P; Yoh, J K; Yosef, C; Yoshida, T; Yu, I; Yu, S; Yu, Z; Zanetti, A; Zetti, F; Zucchelli, S

    2000-01-01

    A measurement is presented of the two-jet differential cross section, d^3\\sigma/dE_T d\\eta_1 d\\eta_2, at center of mass energy sqrt{s} = 1800 GeV in proton-antiproton collisions. The results are based on an integrated luminosity of 86 pb^-1 collected during 1994-1995 by the CDF collaboration at the Fermilab Tevatron collider. The differential cross section is measured as a function of the transverse energy, E_T, of a jet in the pseudorapidity region 0.1 < |eta_1| < 0.7 for four different pseudorapidity bins of a second jet restricted to 0.1 < |\\eta_2| < 3.0. The results are compared with next-to-leading order QCD calculations determined using the CTEQ4 and MRST sets of parton distribution functions. None of the sets examined in this analysis provides a good description of the data.

  11. Measurement of the forward-backward asymmetry in low-mass bottom-quark pairs produced in proton-antiproton collisions

    CERN Document Server

    Aaltonen, T; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Bae, T; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brigliadori, L; Bromberg, C; Brucken, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Butti, P; Buzatu, A; Calamba, A; Camarda, S; Campanelli, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Cho, K; Chokheli, D; Clark, A; Clarke, C; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Cremonesi, M; Cruz, D; Cuevas, J; Culbertson, R; d'Ascenzo, N; Datta, M; de Barbaro, P; Demortier, L; Marchese, L; Deninno, M; Devoto, F; D'Errico, M; Di Canto, A; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dorigo, M; Driutti, A; Ebina, K; Edgar, R; Erbacher, R; Errede, S; Esham, B; Farrington, S; Ramos, J P Fernández; Field, R; Flanagan, G; Forrest, R; Franklin, M; Freeman, J C; Frisch, H; Funakoshi, Y; Galloni, C; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; López, O González; Gorelov, I; Goshaw, A T; Goulianos, K; Gramellini, E; Grosso-Pilcher, C; da Costa, J Guimaraes; Hahn, S R; Han, J Y; Happacher, F; Hara, K; Hare, M; Harr, R F; Harrington-Taber, T; Hatakeyama, K; Hays, C; Heinrich, J; Herndon, M; Hocker, A; Hong, Z; Hopkins, W; Hou, S; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kambeitz, M; Kamon, T; Karchin, P E; Kasmi, A; Kato, Y; Ketchum, W; Keung, J; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kim, Y J; Kimura, N; Kirby, M; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Kruse, M; Kuhr, T; Kurata, M; Laasanen, A T; Lammel, S; Lancaster, M; Lannon, K; Latino, G; Lee, H S; Lee, J S; Leo, S; Leone, S; Lewis, J D; Limosani, A; Lipeles, E; Lister, A; Liu, Q; Liu, T; Lockwitz, S; Loginov, A; Lucà, A; Lucchesi, D; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maestro, P; Majersky, O; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, P; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McNulty, R; Mehta, A; Mehtala, P; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M J; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Nigmanov, T; Nodulman, L; Noh, S Y; Norniella, O; Oakes, L; Oh, S H; Oh, Y D; Okusawa, T; Orava, R; Ortolan, L; Pagliarone, C; Palencia, E; Palni, P; Papadimitriou, V; Parker, W; Pauletta, G; Paulini, M; Paus, C; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Poprocki, S; Potamianos, K; Prokoshin, F; Pranko, A; Ptohos, F; Punzi, G; Fernández, I Redondo; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodriguez, T; Rolli, S; Ronzani, M; Roser, R; Rosner, J L; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Sakumoto, W K; Sakurai, Y; Santi, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schwarz, T; Scodellaro, L; Scuri, F; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shreyber-Tecker, I; Simonenko, A; Sliwa, K; Smith, J R; Snider, F D; Sorin, V; Song, H; Stancari, M; Denis, R St; Stentz, D; Strologas, J; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thomson, E; Thukral, V; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Ukegawa, F; Uozumi, S; Vázquez, F; Velev, G; Vellidis, C; Vernieri, C; Vidal, M; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wallny, R; Wang, S M; Waters, D; Wester, W C; Whiteson, D; Wicklund, A B; Wilbur, S; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamato, D; Yang, T; Yang, U K; Yang, Y C; Yao, W -M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Zanetti, A M; Zeng, Y; Zhou, C; Zucchelli, S

    2016-01-01

    We report a measurement of the forward-backward asymmetry, $A_{FB}$, in $b\\bar{b}$ pairs produced in proton-antiproton collisions and identified by muons from semileptonic $b$-hadron decays. The event sample was collected at a center-of-mass energy of $\\sqrt{s}=1.96$ TeV with the CDF II detector and corresponds to 6.9 fb$^{-1}$ of integrated luminosity. We obtain an integrated asymmetry of $A_{FB}(b\\bar{b})=(1.2 \\pm 0.7)$\\% at the particle level for $b$-quark pairs with invariant mass, $m_{b\\bar{b}}$, down to $40$ GeV/$c^2$ and measure the dependence of $A_{FB}(b\\bar{b})$ on $m_{b\\bar{b}}$. The results are compatible with expectations from the standard model.

  12. Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb–Pb collisions at √sNN =2.76 TeV

    NARCIS (Netherlands)

    Abelev, B.I.; Adam, J.; Bjelogrlic, S; Chojnacki, M.; de Rooij, R. S.; Grelli, A.; La Pointe, S.L.; Luparello, G.; Mischke, A.; Nooren, G.J.L.; Peitzmann, T.; Reicher, M; Snellings, R.J.M.; Thomas, D; van Leeuwen, M.; Veldhoen, M; Verweij, M.; Zhou, Y.; Zyzak, M.

    2013-01-01

    The elliptic, v2, triangular, v3, and quadrangular, v4, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions, and (anti-)protons in Pb–Pb collisions at View the MathML source with the ALICE detector at the Large Hadron Collider. Results obtained with the eve

  13. Phase Measurement of Cognitive Impairment Specific to Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Carol L., E-mail: armstrongc@email.chop.edu [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Neuro-Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Shera, David M. [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Biostatistics and Epidemiology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Lustig, Robert A. [Department of Radiation Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Phillips, Peter C. [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Neurology and Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States)

    2012-07-01

    Purpose: Memory impairment is an early-delayed effect of radiotherapy (RT). The prospective longitudinal measurement of the cognitive phase effects from RT was conducted on treated and untreated brain tumor patients. The study design investigated semantic vs. perceptual and visual vs. verbal memory to determine the most disease-specific measure of RT-related changes and understanding of the neurotoxicity from RT to the brain. Methods and Materials: Tests of memory that had previously shown RT-related phasic changes were compared with experimental tests of memory to test hypotheses about cognition targeted to the neural toxicity of RT. The results from 41 irradiated and 29 nonirradiated patients with low-grade, supratentorial tumors were analyzed. The methods controlled for comorbid white matter risk, recurrence, interval after treatment, and age (18-69 years). The effects were examined before RT and at three points after RT to 1 year using a mixed effects model that included interval, group, surgical status, medication use, practice, and individual random effects. Four new tests of memory and other candidate cognitive tests were investigated, and a post hoc analysis of a comprehensive battery of tests was performed to identify the cognitive processes most specific to RT. Results: The RT effects on memory were identified in the treated group only; among the new tests of memory and the complete neurocognitive battery, the RT effects were significant only for delayed recall (p < 0.009) and interval to recognize (p < 0.002). Tumor location was not related to the treatment effect. Memory decline was specific to retrieval of semantic memories; a double dissociation of semantic from perceptual visual memory was demonstrated in the RT group. Conclusions: These results implicate memory dependent on the semantic cortex and the hippocampal memory system. A cognitive measurement that is brief but specific to neural mechanisms is effective and feasible for studies of RT damage.

  14. Antiproton cloud compression in the ALPHA apparatus at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, A., E-mail: andrea.gutierrez@triumf.ca [University of British Columbia, Department of Physics and Astronomy (Canada); Ashkezari, M. D. [Simon Fraser University, Department of Physics (Canada); Baquero-Ruiz, M. [University of California at Berkeley, Department of Physics (United States); Bertsche, W. [University of Manchester, School of Physics and Astronomy (United Kingdom); Burrows, C. [Swansea University, Department of Physics, College of Science (United Kingdom); Butler, E. [Centre for Cold Matter, Imperial College (United Kingdom); Capra, A. [York University, Department of Physics and Astronomy (Canada); Cesar, C. L. [Universidade Federal do Rio de Janeiro, Instituto de Física (Brazil); Charlton, M. [Swansea University, Department of Physics, College of Science (United Kingdom); Dunlop, R. [Simon Fraser University, Department of Physics (Canada); Eriksson, S. [Swansea University, Department of Physics, College of Science (United Kingdom); Evetts, N. [University of British Columbia, Department of Physics and Astronomy (Canada); Fajans, J. [University of California at Berkeley, Department of Physics (United States); Friesen, T. [Aarhus University, Department of Physics and Astronomy (Denmark); Fujiwara, M. C.; Gill, D. R. [TRIUMF (Canada); Hangst, J. S. [Aarhus University, Department of Physics and Astronomy (Denmark); Hardy, W. N. [University of British Columbia, Department of Physics and Astronomy (Canada); Hayden, M. E. [Simon Fraser University, Department of Physics (Canada); Isaac, C. A. [Swansea University, Department of Physics, College of Science (United Kingdom); and others

    2015-11-15

    We have observed a new mechanism for compression of a non-neutral plasma, where antiprotons embedded in an electron plasma are compressed by a rotating wall drive at a frequency close to the sum of the axial bounce and rotation frequencies. The radius of the antiproton cloud is reduced by up to a factor of 20 and the smallest radius measured is ∼ 0.2 mm. When the rotating wall drive is applied to either a pure electron or pure antiproton plasma, no compression is observed in the frequency range of interest. The frequency range over which compression is evident is compared to the sum of the antiproton bounce frequency and the system’s rotation frequency. It is suggested that bounce resonant transport is a likely explanation for the compression of antiproton clouds in this regime.

  15. Evaporative Cooling of Antiprotons to Cryogenic Temperatures

    CERN Document Server

    Andresen, G B; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A; Hydomako, R; Jonsell, S; Kurchaninov, L; Lambo, R; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wilding, D; Wurtele, J S; Yamazaki, Y

    2010-01-01

    We report the application of evaporative cooling to clouds of trapped antiprotons, resulting in plasmas with measured temperature as low as 9~K. We have modeled the evaporation process for charged particles using appropriate rate equations. Good agreement between experiment and theory is observed, permitting prediction of cooling efficiency in future experiments. The technique opens up new possibilities for cooling of trapped ions and is of particular interest in antiproton physics, where a precise CPT test on trapped antihydrogen is a long-standing goal.

  16. Antiproton Annihilation Propulsion

    Science.gov (United States)

    1985-09-01

    propulsion system, a nuclear thermal hydrogen propulsion system, and an antiproton annihilation propulsion system. Since hauling chemical fuel into low...greater. Section 8.4 and Appendix B contain a comparative cost study of a storable chemical fuel propulsion system, a liquid oxygen/liquid hydrogen

  17. Antiproton Cancer Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels

    of the secondary particles from the antiproton annihilation exihibt high-LET properties. Additionally, the high energy pions are leaving the target with minimal interactions and can be detected external to the body providing a real time feedback on the exact location of the energy deposition. In recent years, we...

  18. Measurement of the inclusive jet cross section in proton-antiproton collisions at the center-of-mass energy of 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Voutilainen, Mikko Antero [Univ. of Helsinki (Finland)

    2008-07-01

    This thesis studies the high-energy collisions of protons and antiprotons. The data used in the measurement were collected during 2004-2005 with the D0 detector at the Tevatron Collider of the Fermi National Accelerator Laboratory and correspond to 0.7 fb-1 of integrated luminosity. High energy hadron collisions usually produce collimated sprays of particles called jets. The energy of the jets is measured using a liquid Argon-Uranium calorimeter and the production angle is determined with the help of silicon microstrip and scintillating fiber trackers. The inclusive jet cross section in proton-antiproton collisions is measured as a function of jet transverse momentum pT in six bins of jet rapidity at the center-of-mass energy √s = 1.96 TeV. The measurement covers jet transerve momenta from 50 GeV up to 600 GeV and jet rapidities up to |y| = 2.4. The data are collected using a set of seven single jet triggers. Event and jet cuts are applied to remove non-physical backgrounds and cosmic-ray interactions. The data are corrected for jet energy calibration, cut and trigger efficiencies and finite jet pT resolution. The corrections are determined from data and the methods are tested with Monte Carlo simulation. The main experimental challenges in the measurement are the calibration of jet energies and the determination of the jet pT resolution. New methods are developed for the jet energy calibration that take into account physical differences between the {gamma}+jet and dijet calibration samples arising from quark and gluon jet differences. The uncertainty correlations are studied and provided as a set of uncertainty sources. The production of particle jets in hadron collisions is described by the theory of quantum chromodynamics (QCD). When the transverse jet momentum is large, the contributions from long-distance physics processes are small and the production rates of jets can be predicted by perturbative QCD. The

  19. Sci—Fri PM: Dosimetry—02: A Nested Neutron Spectrometer to Measure Neutron Spectra in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Maglieri, R; Seuntjens, J; Kildea, J [Medical Physics Unit, McGill University, Montreal, Qc (Canada); Licea, A [Canadian Nuclear Safety Commission CNSC, Ottawa, Ontario (Canada)

    2014-08-15

    During high-energy radiotherapy treatments, neutrons are produced in the head of the linac through photonuclear interactions. This has been a concern for many years as photoneutrons contribute to the accepted, yet unwanted, out-of-field doses that pose an iatrogenic risk to patients and an occupational risk to personnel. Presently, in-room neutron measurements are difficult and time-consuming and have traditionally been carried out using Bonner spheres with activation foils and TLDs. In this work, a new detector, the Nested Neutron Spectrometer (NNS) is tested for use in radiotherapy bunkers. The NNS is designed for easy handling and is more practical than the traditional Bonner spheres. The NNS, operated in current mode, was used to measure the dose equivalent, average energy and energy spectrum at several positions in a radiotherapy bunker. The average energy and spectra were compared to Monte Carlo simulations while the dose equivalent was compared to bubble detector measurements. The average energies, as measured by the NNS and Monte Carlo simulations, differed by approximately 30% across the bunker. Measurements of the dose equivalent using the NNS and the bubble detectors agreed within 50% in the maze and less than 10% close to the linac head. Apart from some discrepancies at thermal energies, we also found reasonable agreement between NNS-measured and Monte Carlo-simulated spectra at a number of locations within our radiotherapy bunker. Our results demonstrate that the NNS is a suitable detector to be used in high dose-rate radiotherapy environments.

  20. Calculated LET spectrum from antiproton beams stopping in water

    CERN Document Server

    Bassler, Niels

    2009-01-01

    Antiprotons have been proposed as a potential modality for radiotherapy because the annihilation at the end of range leads to roughly a doubling of physical dose in the Bragg peak region. So far it has been anticipated that the radiobiology of antiproton beams is similar to that of protons in the entry region of the beam, but very different in the annihilation region, due to the expected high-LET components resulting from the annihilation. On closer inspection we find that calculations of dose averaged LET in the entry region may suggest that the RBE of antiprotons in the plateau region could significantly differ from unity, which seems to warrant closer inspection of the radiobiology in this region. Materials and Methods. Monte Carlo simulations using FLUKA were performed for calculating the entire particle spectrum of a beam of 126 MeV antiprotons hitting a water phantom. Results and Discussion. In the plateau region of the simulated antiproton beam we observe a dose-averaged unrestrict...

  1. Midrapidity antiproton-to-proton ratio in pp collisons at sqrt[s]=0.9 and 7 TeV measured by the ALICE experiment.

    Science.gov (United States)

    Aamodt, K; Abel, N; Abeysekara, U; Abrahantes Quintana, A; Abramyan, A; Adamová, D; Aggarwal, M M; Aglieri Rinella, G; Agocs, A G; Aguilar Salazar, S; Ahammed, Z; Ahmad, A; Ahmad, N; Ahn, S U; Akimoto, R; Akindinov, A; Aleksandrov, D; Alessandro, B; Alfaro Molina, R; Alici, A; Almaráz Aviña, E; Alme, J; Alt, T; Altini, V; Altinpinar, S; Andrei, C; Andronic, A; Anelli, G; Angelov, V; Anson, C; Anticić, T; Antinori, F; Antinori, S; Antipin, K; Antończyk, D; Antonioli, P; Anzo, A; Aphecetche, L; Appelshäuser, H; Arcelli, S; Arceo, R; Arend, A; Armesto, N; Arnaldi, R; Aronsson, T; Arsene, I C; Asryan, A; Augustinus, A; Averbeck, R; Awes, T C; Aystö, J; Azmi, M D; Bablok, S; Bach, M; Badalà, A; Baek, Y W; Bagnasco, S; Bailhache, R; Bala, R; Baldisseri, A; Baldit, A; Bán, J; Barbera, R; Barnaföldi, G G; Barnby, L S; Barret, V; Bartke, J; Barile, F; Basile, M; Basmanov, V; Bastid, N; Bathen, B; Batigne, G; Batyunya, B; Baumann, C; Bearden, I G; Becker, B; Belikov, I; Bellwied, R; Belmont-Moreno, E; Belogianni, A; Benhabib, L; Beole, S; Berceanu, I; Bercuci, A; Berdermann, E; Berdnikov, Y; Betev, L; Bhasin, A; Bhati, A K; Bianchi, L; Bianchi, N; Bianchin, C; Bielcík, J; Bielcíková, J; Bilandzic, A; Bimbot, L; Biolcati, E; Blanc, A; Blanco, F; Blanco, F; Blau, D; Blume, C; Boccioli, M; Bock, N; Bogdanov, A; Bøggild, H; Bogolyubsky, M; Bohm, J; Boldizsár, L; Bombara, M; Bombonati, C; Bondila, M; Borel, H; Borisov, A; Bortolin, C; Bose, S; Bosisio, L; Bossú, F; Botje, M; Böttger, S; Bourdaud, G; Boyer, B; Braun, M; Braun-Munzinger, P; Bravina, L; Bregant, M; Breitner, T; Bruckner, G; Brun, R; Bruna, E; Bruno, G E; Budnikov, D; Buesching, H; Buncic, P; Busch, O; Buthelezi, Z; Caffarri, D; Cai, X; Caines, H; Calvo, E; Camacho, E; Camerini, P; Campbell, M; Canoa Roman, V; Capitani, G P; Cara Romeo, G; Carena, F; Carena, W; Carminati, F; Casanova Díaz, A; Caselle, M; Castillo Castellanos, J; Castillo Hernandez, J F; Catanescu, V; Cattaruzza, E; Cavicchioli, C; Cerello, P; Chambert, V; Chang, B; Chapeland, S; Charpy, A; Charvet, J L; Chattopadhyay, S; Chattopadhyay, S; Cherney, M; Cheshkov, C; Cheynis, B; Chiavassa, E; Chibante Barroso, V; Chinellato, D D; Chochula, P; Choi, K; Chojnacki, M; Christakoglou, P; Christensen, C H; Christiansen, P; Chujo, T; Chuman, F; Cicalo, C; Cifarelli, L; Cindolo, F; Cleymans, J; Cobanoglu, O; Coffin, J-P; Coli, S; Colla, A; Conesa Balbastre, G; Conesa Del Valle, Z; Conner, E S; Constantin, P; Contin, G; Contreras, J G; Corrales Morales, Y; Cormier, T M; Cortese, P; Cortés Maldonado, I; Cosentino, M R; Costa, F; Cotallo, M E; Crescio, E; Crochet, P; Cuautle, E; Cunqueiro, L; Cussonneau, J; Dainese, A; Dalsgaard, H H; Danu, A; Das, I; Dash, A; Dash, S; de Barros, G O V; De Caro, A; de Cataldo, G; de Cuveland, J; De Falco, A; De Gaspari, M; de Groot, J; De Gruttola, D; De Marco, N; De Pasquale, S; De Remigis, R; de Rooij, R; de Vaux, G; Delagrange, H; Delgado, Y; Dellacasa, G; Deloff, A; Demanov, V; Dénes, E; Deppman, A; D'Erasmo, G; Derkach, D; Devaux, A; Di Bari, D; Di Giglio, C; Di Liberto, S; Di Mauro, A; Di Nezza, P; Dialinas, M; Díaz, L; Díaz, R; Dietel, T; Divià, R; Djuvsland, O; Dobretsov, V; Dobrin, A; Dobrowolski, T; Dönigus, B; Domínguez, I; Don, D M M; Dordic, O; Dubey, A K; Dubuisson, J; Ducroux, L; Dupieux, P; Dutta Majumdar, A K; Dutta Majumdar, M R; Elia, D; Emschermann, D; Enokizono, A; Espagnon, B; Estienne, M; Esumi, S; Evans, D; Evrard, S; Eyyubova, G; Fabjan, C W; Fabris, D; Faivre, J; Falchieri, D; Fantoni, A; Fasel, M; Fateev, O; Fearick, R; Fedunov, A; Fehlker, D; Fekete, V; Felea, D; Fenton-Olsen, B; Feofilov, G; Fernández Téllez, A; Ferreiro, E G; Ferretti, A; Ferretti, R; Figueredo, M A S; Filchagin, S; Fini, R; Fionda, F M; Fiore, E M; Floris, M; Fodor, Z; Foertsch, S; Foka, P; Fokin, S; Formenti, F; Fragiacomo, E; Fragkiadakis, M; Frankenfeld, U; Frolov, A; Fuchs, U; Furano, F; Furget, C; Fusco Girard, M; Gaardhøje, J J; Gadrat, S; Gagliardi, M; Gago, A; Gallio, M; Ganoti, P; Ganti, M S; Garabatos, C; García Trapaga, C; Gebelein, J; Gemme, R; Germain, M; Gheata, A; Gheata, M; Ghidini, B; Ghosh, P; Giraudo, G; Giubellino, P; Gladysz-Dziadus, E; Glasow, R; Glässel, P; Glenn, A; Gómez Jiménez, R; González Santos, H; González-Trueba, L H; González-Zamora, P; Gorbunov, S; Gorbunov, Y; Gotovac, S; Gottschlag, H; Grabski, V; Grajcarek, R; Grelli, A; Grigoras, A; Grigoras, C; Grigoriev, V; Grigoryan, A; Grigoryan, S; Grinyov, B; Grion, N; Gros, P; Grosse-Oetringhaus, J F; Grossiord, J-Y; Grosso, R; Guber, F; Guernane, R; Guerra, C; Guerzoni, B; Gulbrandsen, K; Gulkanyan, H; Gunji, T; Gupta, A; Gupta, R; Gustafsson, H-A; Gutbrod, H; Haaland, O; Hadjidakis, C; Haiduc, M; Hamagaki, H; Hamar, G; Hamblen, J; Han, B H; Harris, J W; Hartig, M; Harutyunyan, A; Hasch, D; Hasegan, D; Hatzifotiadou, D; Hayrapetyan, A; Heide, M; Heinz, M; Helstrup, H; Herghelegiu, A; Hernández, C; Herrera Corral, G; Herrmann, N; Hetland, K F; Hicks, B; Hiei, A; Hille, P T; Hippolyte, B; Horaguchi, T; Hori, Y; Hristov, P; 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Kondratyeva, N; Konevskih, A; Kornaś, E; Kour, R; Kowalski, M; Kox, S; Kozlov, K; Kral, J; Králik, I; Kramer, F; Kraus, I; Kravcáková, A; Krawutschke, T; Krivda, M; Krumbhorn, D; Krus, M; Kryshen, E; Krzewicki, M; Kucheriaev, Y; Kuhn, C; Kuijer, P G; Kumar, L; Kumar, N; Kupczak, R; Kurashvili, P; Kurepin, A; Kurepin, A N; Kuryakin, A; Kushpil, S; Kushpil, V; Kutouski, M; Kvaerno, H; Kweon, M J; Kwon, Y; La Rocca, P; Lackner, F; Ladrón de Guevara, P; Lafage, V; Lal, C; Lara, C; Larsen, D T; Laurenti, G; Lazzeroni, C; Le Bornec, Y; Le Bris, N; Lee, H; Lee, K S; Lee, S C; Lefèvre, F; Lenhardt, M; Leistam, L; Lehnert, J; Lenti, V; León, H; León Monzón, I; León Vargas, H; Lévai, P; Li, X; Li, Y; Lietava, R; Lindal, S; Lindenstruth, V; Lippmann, C; Lisa, M A; Liu, L; Loginov, V; Lohn, S; Lopez, X; López Noriega, M; López-Ramírez, R; López Torres, E; Løvhøiden, G; Lozea Feijo Soares, A; Lu, S; Lunardon, M; Luparello, G; Luquin, L; Lutz, J-R; Ma, K; Ma, R; Madagodahettige-Don, D M; Maevskaya, A; 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    2010-08-13

    The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at sqrt[s]=0.9 and 7 TeV during the initial running periods of the Large Hadron Collider. The measurement covers the transverse momentum interval 0.45measured to be R_{|y|<0.5}=0.957±0.006(stat)±0.014(syst) at 0.9 TeV and R_{|y|<0.5}=0.991±0.005(stat)±0.014(syst) at 7 TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

  2. Midrapidity antiproton-to-proton ratio in pp collisions at $\\sqrt{s} = 0.9$ and $7$~TeV measured by the ALICE experiment

    CERN Document Server

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Potukuchi, B.; Pouthas, J.; Prasad, S.K.; Preghenella, R.; Prino, F.; Pruneau, C.A.; Pshenichnov, I.; Puddu, G.; Pujahari, P.; Pulvirenti, A.; Punin, A.; Punin, V.; Putis, M.; Putschke, J.; Quercigh, E.; Rachevski, A.; Rademakers, A.; Radomski, S.; Raiha, T.S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rodriguez Cahuantzi, M.; Rammler, M.; Raniwala, R.; Raniwala, S.; Rasanen, S.S.; Rashevskaya, I.; Rath, S.; Read, K.F.; Real, J.S.; Redlich, K.; Renfordt, R.; Reolon, A.R.; Reshetin, A.; Rettig, F.; Revol, J.-P.; Reygers, K.; Ricaud, H.; Riccati, L.; Ricci, R.A.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Rivetti, A.; Roed, K.; Rohrich, D.; Roman Lopez, S.; Romita, R.; Ronchetti, F.; Rosinsky, P.; Rosnet, P.; Rossegger, S.; Rossi, A.; Roukoutakis, F.; Rousseau, S.; Roy, C.; Roy, P.; Rubio-Montero, A.J.; Rui, R.; Rusanov, I.; Russo, G.; Ryabinkin, E.; Rybicki, A.; Sadovsky, S.; Safarik, K.; Sahoo, R.; Saini, J.; Saiz, P.; Sakata, D.; Salgado, C.A.; Salgueiro Domingues da Silva, R.; 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Song, M.; Soos, C.; Soramel, F.; Soyk, D.; Spyropoulou-Stassinaki, M.; Srivastava, B.K.; Stachel, J.; Staley, F.; Stan, E.; Stefanek, G.; Stefanini, G.; Steinbeck, T.; Stenlund, E.; Steyn, G.; Stocco, D.; Stock, R.; Stolpovsky, P.; Strmen, P.; Suaide, A.A.P.; Subieta Vasquez, M.A.; Sugitate, T.; Suire, C.; Sumbera, M.; Susa, T.; Swoboda, D.; Symons, J.; Szanto de Toledo, A.; Szarka, I.; Szostak, A.; Szuba, M.; Tadel, M.; Tagridis, C.; Takahara, A.; Takahashi, J.; Tanabe, R.; Tapia Takaki, J.D.; Taureg, H.; Tauro, A.; Tavlet, M.; Tejeda Munoz, G.; Telesca, A.; Terrevoli, C.; Thaeder, Jochen Mathias; Tieulent, R.; Tlusty, D.; Toia, A.; Tolyhy, T.; Torcato de Matos, C.; Torii, H.; Torralba, G.; Toscano, L.; Tosello, F.; Tournaire, A.; Traczyk, T.; Tribedy, P.; Troger, G.; Truesdale, D.; Trzaska, W.H.; Tsiledakis, G.; Tsilis, E.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Turvey, A.; Tveter, T.S.; Tydesjo, H.; Tywoniuk, K.; Ulery, J.; Ullaland, K.; Uras, A.; Urban, J.; Urciuoli, G.M.; Usai, G.L.; 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Zavada, P.; Zbroszczyk, H.; Zelnicek, P.; Zenin, A.; Zepeda, A.; Zgura, I.; Zhalov, M.; Zhang, X.; Zhou, D.; Zhou, S.; Zhu, J.; Zichichi, A.; Zinchenko, A.; Zinovjev, G.; Zoccarato, Y.; Zychacek, V.; Zynovyev, M.

    2010-01-01

    The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at $\\sqrt{s} = 0.9$ and $7$~TeV during the initial running periods of the Large Hadron Collider(LHC). The measurement covers the transverse momentum interval $0.45 < p_{\\rm{t}} < 1.05$~GeV/$c$ and rapidity $|y| < 0.5$. The ratio is measured to be $R_{|y| < 0.5} = 0.957 \\pm 0.006 (stat.) \\pm 0.014 (syst.)$ at $0.9$~TeV and $R_{|y| < 0.5} = 0.991 \\pm 0.005 (stat.) \\pm 0.014 (syst.)$ at $7$~TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

  3. Bubble chamber: antiproton annihilation

    CERN Multimedia

    1971-01-01

    These images show real particle tracks from the annihilation of an antiproton in the 80 cm Saclay liquid hydrogen bubble chamber. A negative kaon and a neutral kaon are produced in this process, as well as a positive pion. 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.

  4. ALPHA freezes antiprotons

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Laboratories like CERN can routinely produce many different types of antiparticles. In 1995, the PS210 experiment formed the first antihydrogen atoms and a few years later, in 2002, ATRAP and ATHENA were already able to produce several thousand of them. However, no experiment in the world has succeeded in ‘trapping’ these anti-atoms in order to study them. This is the goal of the ALPHA experiment, which has recently managed to cool down the antiprotons to just a few Kelvin. This represents a major step towards trapping the anti-atom, thus opening a new avenue into the investigation of antimatter properties.   Members of the ALPHA collaboration working on the apparatus in the Antiproton Decelerator experimental hall at CERN. Just like the atom, the anti-atom is neutral. Unlike the atom, the anti-atom is made up of antiprotons (as opposed to protons in the atom) and positrons (as opposed to electrons). In order to thoroughly study the properties of the anti-atoms, scien...

  5. Extra Low ENergy Antiproton

    CERN Multimedia

    To produce dense antiproton beams at very low energies (110 keV), it has been proposed to install a small decelerator ring between the existing AD ring and the experimental area. Phase-space blowup during deceleration is compensated by electron cooling such that the final emittances are comparable to the 5MeV beam presently delivered by the AD. An immediate consequence is a significant increase in the number of trapped antiprotons at the experiments as outlined in the proposal CERN/SPSC-2009-026; SPCS-P-338. This report describes the machine parameters and layout of the proposal ELENA (Extra Low ENergy Antiproton)ring also gives an approximate estimate of cost and manpower needs. Since the initial estimate, published in 2007 (CERN-AB-2007-079), the ELENA design has evolved considerably. This is due to a new location in the AD hall to acommodate for the possibility of another experimental zone, as suggested by the SPCS, and also due to improvements in the ring optics and layout. The cost estimate that is prese...

  6. Three dimensional biological dose distribution of antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Tegami, Sara; Boll, Rebecca; Sellner, Stefan [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Welsch, Carsten P. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Cockcroft Institute, University of Liverpool (United Kingdom); Holzscheiter, Michael H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); University of New Mexico, Albuquerque (United States)

    2010-07-01

    The goal of external beam cancer therapy is to destroy the tumour while sparing the healthy tissue around it. In hadron therapy, the dose profile of heavy charged particles satisfies this request, because most of the energy is deposited at the end of the particle path, in the Bragg peak. Antiprotons are even more promising, thanks to the extra energy released by annihilation when captured in a normal atom at the end of range. The aim of the AD-4/ACE experiment at CERN is to determine the increase in biological dose near the Bragg peak due to densely ionizing particles emanating from the annihilation of antiprotons. Initial experiments showed the damage to cells inflicted at the end of the beam for identical damage at the skin level to be four times higher for antiprotons than for protons. The radiation field in a spread-out Bragg peak produced with antiprotons is highly mixed and for proper dose planning knowledge of linear energy transfer (LET) and relative biological efficiency (RBE) at any point in the target is needed. We are studying a number of detection methods for their response to mixed radiation fields with the goal to obtain a direct measurement of the 3D LET distribution and report on first results.

  7. Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at $\\sqrt{s_{NN}}$=2.76 TeV

    CERN Document Server

    Abelev, Betty; Adamova, Dagmar; Adare, Andrew Marshall; Aggarwal, Madan; Aglieri Rinella, Gianluca; Agocs, Andras Gabor; Agostinelli, Andrea; Aguilar Salazar, Saul; Ahammed, Zubayer; Ahmad, Arshad; Ahmad, Nazeer; Ahn, Sang Un; Akindinov, Alexander; Aleksandrov, Dmitry; Alessandro, Bruno; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Almaraz Avina, Erick Jonathan; Alme, Johan; Alt, Torsten; Altini, Valerio; Altinpinar, Sedat; Altsybeev, Igor; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshauser, Harald; Arbor, Nicolas; Arcelli, Silvia; Armesto, Nestor; Arnaldi, Roberta; Aronsson, Tomas Robert; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Awes, Terry; Aysto, Juha Heikki; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bailhache, Raphaelle Marie; Bala, Renu; Baldini Ferroli, Rinaldo; Baldisseri, Alberto; 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de Rooij, Raoul Stefan; Delagrange, Hugues; Deloff, Andrzej; Demanov, Vyacheslav; Denes, Ervin; Deppman, Airton; Di Bari, Domenico; Di Giglio, Carmelo; Di Liberto, Sergio; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Dominguez, Isabel; Donigus, Benjamin; Dordic, Olja; Driga, Olga; Dubey, Anand Kumar; Ducroux, Laurent; Dupieux, Pascal; Dutta Majumdar, AK; Dutta Majumdar, Mihir Ranjan; Elia, Domenico; Emschermann, David Philip; Engel, Heiko; Erdal, Hege Austrheim; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Evans, David; Eyyubova, Gyulnara; Fabris, Daniela; Faivre, Julien; Falchieri, Davide; Fantoni, Alessandra; Fasel, Markus; Fearick, Roger Worsley; Fedunov, Anatoly; Fehlker, Dominik; Feldkamp, Linus; Felea, Daniel; Fenton-Olsen, Bo; Feofilov, Grigory; Fernandez Tellez, Arturo; Ferretti, Alessandro; Ferretti, Roberta; Figiel, Jan; Figueredo, Marcel; 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Innocenti, Gian Michele; Ippolitov, Mikhail; Irfan, Muhammad; Ivan, Cristian George; Ivanov, Andrey; Ivanov, Marian; Ivanov, Vladimir; Ivanytskyi, Oleksii; Jacholkowski, Adam Wlodzimierz; Jacobs, Peter; Jangal, Swensy Gwladys; Janik, Malgorzata Anna; Janik, Rudolf; Jayarathna, Sandun; Jena, Satyajit; Jha, Deeptanshu Manu; Jimenez Bustamante, Raul Tonatiuh; Jirden, Lennart; Jones, Peter Graham; Jung, Hyung Taik; Jusko, Anton; Kakoyan, Vanik; Kalcher, Sebastian; Kalinak, Peter; Kalliokoski, Tuomo Esa Aukusti; Kalweit, Alexander Philipp; Kanaki, Kalliopi; Kang, Ju Hwan; Kaplin, Vladimir; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karpechev, Evgeny; Kazantsev, Andrey; Kebschull, Udo Wolfgang; Keidel, Ralf; Khan, Mohisin Mohammed; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Dong Jo; Kim, Do Won; Kim, Jonghyun; Kim, Jin Sook; Kim, Minwoo; Kim, Mimae; Kim, Se Yong; Kim, Seon Hee; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Klay, Jennifer Lynn; Klein, Jochen; Klein-Bosing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Koch, Kathrin; Kohler, Markus; Kolojvari, Anatoly; Kondratiev, Valery; Kondratyeva, Natalia; Konevskih, Artem; Korneev, Andrey; Kour, Ravjeet; Kowalski, Marek; Kox, Serge; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kramer, Frederick; Kraus, Ingrid Christine; Krawutschke, Tobias; Krelina, Michal; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Krus, Miroslav; Kryshen, Evgeny; Krzewicki, Mikolaj; Kucheriaev, Yury; Kuhn, Christian Claude; Kuijer, Paul; Kulakov, Igor; Kurashvili, Podist; Kurepin, A; Kurepin, AB; Kuryakin, Alexey; Kushpil, Svetlana; Kushpil, Vasily; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Ladron de Guevara, Pedro; Lakomov, Igor; Langoy, Rune; Lara, Camilo Ernesto; Lardeux, Antoine Xavier; Lazzeroni, Cristina; Le Bornec, Yves; Lea, Ramona; Lechman, Mateusz; Lee, Graham Richard; 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Margagliotti, Giacomo Vito; Margotti, Anselmo; Marin, Ana Maria; Marin Tobon, Cesar Augusto; Markert, Christina; Martashvili, Irakli; Martinengo, Paolo; Martinez, Mario Ivan; Martinez Davalos, Arnulfo; Martinez Garcia, Gines; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Mastromarco, Mario; Mastroserio, Annalisa; Matthews, Zoe Louise; Matyja, Adam Tomasz; Mayani, Daniel; Mayer, Christoph; Mazer, Joel; Mazzoni, Alessandra Maria; Meddi, Franco; Menchaca-Rocha, Arturo Alejandro; Mercado Perez, Jorge; Meres, Michal; Miake, Yasuo; Milano, Leonardo; Milosevic, Jovan; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz; Mitu, Ciprian Mihai; Mlynarz, Jocelyn; Mohanty, Ajit Kumar; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Monteno, Marco; Montes, Esther; Moon, Taebong; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Moretto, Sandra; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhuri, Sanjib; Mukherjee, Maitreyee; Muller, Hans; Munhoz, Marcelo; Musa, Luciano; Musso, Alfredo; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Nattrass, Christine; Naumov, Nikolay; Navin, Sparsh; Nayak, Tapan Kumar; Nazarenko, Sergey; Nazarov, Gleb; Nedosekin, Alexander; Nicassio, Maria; Niculescu, Mihai; Nielsen, Borge Svane; Niida, Takafumi; Nikolaev, Sergey; Nikolic, Vedran; Nikulin, Sergey; Nikulin, Vladimir; Nilsen, Bjorn Steven; Nilsson, Mads Stormo; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Novitzky, Norbert; Nyanin, Alexandre; Nyatha, Anitha; Nygaard, Casper; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Oleniacz, Janusz; Oppedisano, Chiara; Ortona, Giacomo; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Pachmayer, Yvonne Chiara; Pachr, Milos; Padilla, Fatima; Pagano, Paola; Paic, Guy; Painke, Florian; Pajares, Carlos; Pal, S; Pal, Susanta Kumar; Palaha, Arvinder Singh; Palmeri, Armando; Papikyan, Vardanush; Pappalardo, Giuseppe; Park, Woo Jin; Passfeld, Annika; Patalakha, Dmitri Ivanovich; Paticchio, Vincenzo; Pavlinov, Alexei; Pawlak, Tomasz Jan; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitri; Perez Lara, Carlos Eugenio; Perez Lezama, Edgar; Perini, Diego; Perrino, Davide; Peryt, Wiktor Stanislaw; Pesci, Alessandro; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petran, Michal; Petris, Mariana; Petrov, Plamen Rumenov; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Piccotti, Anna; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Pitz, Nora; Piuz, Francois; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polichtchouk, Boris; Pop, Amalia; Porteboeuf-Houssais, Sarah; Pospisil, Vladimir; Potukuchi, Baba; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puchagin, Sergey; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Pujol Teixido, Jordi; Pulvirenti, Alberto; Punin, Valery; Putis, Marian; Putschke, Jorn Henning; Quercigh, Emanuele; Qvigstad, Henrik; Rachevski, Alexandre; Rademakers, Alphonse; Radomski, Sylwester; Raiha, Tomi Samuli; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Ramirez Reyes, Abdiel; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reichelt, Patrick; Reicher, Martijn; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riccati, Lodovico; Ricci, Renato Angelo; Richert, Tuva; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Rodrigues Fernandes Rabacal, Bartolomeu; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roed, Ketil; Rohr, David; Rohrich, Dieter; Romita, Rosa; Ronchetti, Federico; Rosnet, Philippe; Rossegger, Stefan; Rossi, Andrea; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Rybicki, Andrzej; Sadovsky, Sergey; Safarik, Karel; Sahoo, Raghunath; Sahu, Pradip Kumar; Saini, Jogender; Sakaguchi, Hiroaki; Sakai, Shingo; Sakata, Dosatsu; Salgado, Carlos Albert; Salzwedel, Jai; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sanchez Castro, Xitzel; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Sano, Satoshi; Santo, Rainer; Santoro, Romualdo; Sarkamo, Juho Jaako; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schreiner, Steffen; Schuchmann, Simone; Schukraft, Jurgen; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Patrick Aaron; Scott, Rebecca; Segato, Gianfranco; Selyuzhenkov, Ilya; Senyukov, Serhiy; Seo, Jeewon; Serci, Sergio; Serradilla, Eulogio; Sevcenco, Adrian; Shabetai, Alexandre; Shabratova, Galina; Shahoyan, Ruben; Sharma, Natasha; Sharma, Satish; Shigaki, Kenta; Shimomura, Maya; Shtejer, Katherin; Sibiriak, Yury; Siciliano, Melinda; Sicking, Eva; Siddhanta, Sabyasachi; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, catherine; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Skjerdal, Kyrre; Smakal, Radek; Smirnov, Nikolai; Snellings, Raimond; Sogaard, Carsten; Soltz, Ron Ariel; Son, Hyungsuk; Song, Jihye; Song, Myunggeun; Soos, Csaba; Soramel, Francesca; Sputowska, Iwona; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Stefanini, Giorgio; Steinbeck, Timm Morten; Steinpreis, Matthew; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Stolpovskiy, Mikhail; Strabykin, Kirill; Strmen, Peter; Suaide, Alexandre Alarcon do Passo; Subieta Vasquez, Martin Alfonso; Sugitate, Toru; Suire, Christophe Pierre; Sukhorukov, Mikhail; Sultanov, Rishat; Sumbera, Michal; Susa, Tatjana; Szanto de Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szostak, Artur Krzysztof; Szymanski, Maciej; Takahashi, Jun; Tapia Takaki, Daniel Jesus; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terrevoli, Cristina; Thader, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony; Toia, Alberica; Torii, Hisayuki; Tosello, Flavio; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ulery, Jason Glyndwr; Ullaland, Kjetil; Ulrich, Jochen; Uras, Antonio; Urban, Jozef; Urciuoli, Guido Marie; Usai, Gianluca; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; van der Kolk, Naomi; van Leeuwen, Marco; Vande Vyvre, Pierre; Vannucci, Luigi; Vargas, Aurora Diozcora; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vechernin, Vladimir; Veldhoen, Misha; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Vikhlyantsev, Oleg; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Viyogi, Yogendra; Vodopianov, Alexander; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; von Haller, Barthelemy; Vranic, Danilo; Øvrebekk, Gaute; Vrlakova, Janka; Vulpescu, Bogdan; Vyushin, Alexey; Wagner, Boris; Wagner, Vladimir; Wan, Renzhuo; Wang, Dong; Wang, Mengliang; Wang, Yifei; Wang, Yaping; Watanabe, Kengo; Weber, Michael; Wessels, Johannes; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Alexander; Wilk, Grzegorz Andrzej; Williams, Crispin; Windelband, Bernd Stefan; Xaplanteris Karampatsos, Leonidas; Yaldo, Chris G; Yamaguchi, Yorito; Yang, Hongyan; Yang, Shiming; Yasnopolsky, Stanislav; Yi, JunGyu; Yin, Zhongbao; Yoo, In-Kwon; Yoon, Jongik; Yu, Weilin; Yuan, Xianbao; Yushmanov, Igor; Zach, Cenek; Zampolli, Chiara; Zaporozhets, Sergey; Zarochentsev, Andrey; Zavada, Petr; Zaviyalov, Nikolai; Zbroszczyk, Hanna Paulina; Zelnicek, Pierre; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhou, Daicui; Zhou, Fengchu; Zhou, You; Zhu, Jianhui; Zhu, Xiangrong; Zichichi, Antonino; Zimmermann, Alice; Zinovjev, Gennady; Zoccarato, Yannick Denis; Zynovyev, Mykhaylo; Zyzak, Maksym

    2013-01-01

    The elliptic, $v_2$, triangular, $v_3$, and quadrangular, $v_4$, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions, and (anti-)protons in Pb–Pb collisions at $\\sqrt{s_{NN}}$ = 2.76 TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range |$\\eta$|8 GeV/c. The small $p_T$ dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to $p_T$ =8 GeV/c. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least $p_T$ =8 GeV/c indicating that the particle type dependence persists out to high $p_T$.

  8. Measurement of Z+ γ production and search for anomalous triple gauge couplings in proton-antiproton collisions at √S = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jianrong [Duke Univ., Durham, NC (United States)

    2008-01-01

    The author presents a measurement of p$\\bar{p}$ → Zγ + X → e+e-γ + X production using proton-antiproton collisions data collected at the Collider Detector at Fermilab at a center of mass energy of 1.96 TeV. Zγ production provides a direct test of the triple neutral gauge couplings. A measurement of Zγ production cross section and search for anomalous ZZγ and Zγγ couplings are presented. The data presented are from 1.1 fb-1 of p$\\bar{p}$ integrated luminosity collected at the CDF Detector. Electrons from Z decays are selected with Et > 20 Gev. Photons (Et > 7 GeV) are required to be well-separated from the electrons. There are 390 eeγ candidate events found with 1.1 fb-1 of data, compared to the SM prediction of 375.3 ± 25.2 events. The Standard Model prediction for the cross section for p$\\bar{p}$ → e+e-γ + X production at √s = 1.96 TeV is 4.5 ± 0.4 pb. The measured cross section is 4.7 ± 0.6 pb. The cross section and kinematic distributions of the eeγ events are in good agreement with theoretical predictions. Limits on the ZZγ and Zγγ couplings are extracted using the photon Et distribution of eeγ events with meeγ > 100 GeV/c2. These are the first limits measured using CDF Run II data. These limits provide important test of the interaction of the photon and the Z boson.

  9. Centrality dependence of antiproton production in Au+Au collisions

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D.; Bennett, M.J.; Carroll, J.B.; Chiba, J.; Chikanian, A.; Crawford, H.; Cronqvist, M.; Dardenne, Y.; Debbe, R.; Doke, T.; Engelage, J.; Greiner, L.; Hallman, T.J.; Hayano, R.S.; Heckman, H.H.; Kashiwagi, T.; Kikuchi, J.; Kumar, S.; Kuo, C.; Lindstrom, P.J.; Mitchell, J.W.; Nagamiya, S.; Nagle, J.L.; Pope, J.K.; Stankus, P.; Tanaka, K.H.; Welsh, R.C.; Zhan, W. [Brookhaven National Laboratory, Upton, New York (United States)]|[A.W. Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut (United States)]|[University of California at Los Angeles, Los Angeles California (United States)]|[National Laboratory for High Energy Physics (KEK), Tsukuba (Japan)]|[University of California Space Sciences Laboratory, Berkeley California (United States)]|[Waseda University, Tokyo (Japan)]|[University of Tokyo, Tokyo (Japan)]|[Lawrence Berkeley Laboratory, Berkeley California (United States)]|[Universities Space Sciences Research Association/Goddard Space Flight Center, Greenbelt, Maryland (United States)]|[Nevis Laboratory, Columbia University, Irvington, New York (United States)]|[Johns Hopkins University, Baltimore, Maryland (United States); (E878 Collaboration)

    1995-11-13

    We have measured the yields of antiprotons in Au+Au interactions in the rapidity range 1.2{lt}{ital y}{lt}2.8 as a function of centrality using a beam line spectrometer. The shapes of the invariant multiplicity distributions at {ital p}{sub {ital t}}=0 are used to explore the dynamics of antiproton production and annihilation. {copyright} {ital 1995} {ital The} {ital American} {ital Physical} {ital Society}.

  10. AA antiproton production target

    CERN Multimedia

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long (actually a row of 11 rods, each 1 cm long) and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing made of stainless steel. The casing had fins for forced-air cooling. In this picture, the 26 GeV high-intensity beam from the PS enters from the right, where a scintillator screen, with circles every 5 mm in radius, permits precise aim at the target centre. See also 7903034 and 7905094.

  11. AA antiproton production target

    CERN Multimedia

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing of stainless steel. At the entrance to the target assembly was a scintillator screen, imprinted with circles every 5 mm in radius, which allowed to precisely aim the 26 GeV high-intensity proton beam from the PS onto the centre of the target rod. The scintillator screen was a 1 mm thick plate of Cr-doped alumina. See also 7903034 and 7905091.

  12. Antiprotons from dark matter annihilation in the Galaxy: astrophysical uncertainties

    CERN Document Server

    Evoli, Carmelo; Grasso, Dario; Maccione, Luca; Ullio, Piero

    2011-01-01

    The latest years have seen steady progresses in WIMP dark matter (DM) searches, with hints of possible signals suggested by both direct and indirect detection experiments. Antiprotons can play a key role validating those interpretations since they are copiously produced by WIMP annihilations in the Galactic halo, and the secondary antiproton background produced by Cosmic Ray (CR) interactions is predicted with fair accuracy and matches the observed spectrum very well. Using the publicly available numerical DRAGON code, we reconsider antiprotons as a tool to constrain DM models discussing its power and limitations. We provide updated constraints on a wide class of annihilating DM models by comparing our predictions against the most up-to-date ap measurements, taking also into account the latest spectral information on the p, He and other CR nuclei fluxes. Doing that, we probe carefully the uncertainties associated to both secondary and DM originated antiprotons, by using a variety of distinctively different as...

  13. Comparing Cystatin C Changes as a Measure of Renal Function Before and After Radiotherapy in Patients with Stomach Cancer

    Directory of Open Access Journals (Sweden)

    Ahmad Ameri

    2012-01-01

    Full Text Available The objective of this study was to determine and compare Cystatin C changes before and after radiotherapy in patients with stomach cancer who were candidate for radiotherapy. This study was conducted as a prospective cohort one. Eighteen patients with definite diagnosis of stomach cancer under treatment by radiotherapy who presented to Radiotherapy-Oncology Center of Imam Hossein Hospital, Tehran-Iran, and the treatment in all cases was simultaneous chemoradiation with Xeloda were included. In all patients before radiotherapy and after radiotherapy serum creatinine (Cr and Cystatin C were measured simultaneously. Mean cystatin level before treatment (1.2±0.4 was significantly lower than that of post-treatment (1.6±0.36, (P=0.001. Serum Cr level before treatment was 1.15±0.33 and after radiotherapy was 1.08±0.24 and did not show significant difference. Glomerular filtration rate (GFR of the patients before radiotherapy was -46.8 ± 21.0 and after radiotherapy was 43.8±15.8 that did not have significant difference (P=0.146 and also blood urea nitrogen (BUN before radiotherapy was 20.72±3.7 and 20 ± 6.38 after radiotherapy that did not have significant difference (P=0.6. Comparison of the Cystatin C difference with total radiation dose of the kidneys that are put in three dose groups in radiotherapy field had association that in dose of less that 18 gray (Gy the Cystatin C change showed significant and positive association (P=0.027; r=0.52 and about 18-24 Gy the Cystatin C difference showed significant and negative association (P=0.023, r=-0.53. It seems that for evaluating the renal function, serum Cystatin C measurement is preferable than serum Cr. level.

  14. Physics at CERN’s Antiproton Decelerator

    Science.gov (United States)

    Hori, M.; Walz, J.

    2013-09-01

    The Antiproton Decelerator (AD) facility of CERN began operation in 1999 to serve experiments for studies of CPT invariance by precision laser and microwave spectroscopy of antihydrogen (Hbar ) and antiprotonic helium (pbar He) atoms. The first 12 years of AD operation saw cold Hbar synthesized by overlapping clouds of positrons (e+) and antiprotons (pbar ) confined in magnetic Penning traps. Cold Hbar was also produced in collisions between Rydberg positronium (Ps) atoms and pbar . Ground-state Hbar was later trapped for up to ˜1000 s in a magnetic bottle trap, and microwave transitions excited between its hyperfine levels. In the pbar He atom, deep ultraviolet transitions were measured to a fractional precision of (2.3-5)×10-9 by sub-Doppler two-photon laser spectroscopy. From this the antiproton-to-electron mass ratio was determined as M/me=1836.1526736(23), which agrees with the p value known to a similar precision. Microwave spectroscopy of pbar He yielded a measurement of the pbar magnetic moment with a precision of 0.3%. More recently, the magnetic moment of a single pbar confined in a Penning trap was measured with a higher precision, as μ=-2.792845(12)μ in nuclear magnetons. Other results reviewed here include the first measurements of the energy loss (-dE/dx) of 1-100 keV pbar traversing conductor and insulator targets; the cross sections of low-energy (therapy. New experiments under preparation attempt to measure the gravitational acceleration of Hbar or synthesize H. Several other future experiments will also be briefly described.

  15. V-79 Chinese Hamster Cells irradiated with antiprotons, a study of peripheral damage due to medium and long range components of the annihilation radiation

    DEFF Research Database (Denmark)

    Kovacevic, Sandra; Bassler, Niels; Hartley, Oliver

    2009-01-01

    Purpose: Radiotherapy of cancer carries a perceived risk of inducing secondary cancer and other damage due to dose delivered to normal tissue. While expectedly small, this risk must be carefully analysed for all modalities. Especially in the use of exotic particles like pions and antiprotons, which...... annihilate and produce a mixed radiation field when interacting with normal matter nuclei, the biological effective dose far out of field needs to be considered in evaluating this approach. We describe first biological measurements to address the concern that medium and long range annihilation products may...

  16. Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants

    CERN Document Server

    Hayano, R S

    2010-01-01

    Proceedings of the Japan Academy, Series B Vol. 86 (2010) No. 1 P 1-10 Language: Next Article http://dx.doi.org/10.2183/pjab.86.1 JST.JSTAGE/pjab/86.1 Reviews Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants Ryugo S. HAYANO1) 1) Department of Physics, The University of Tokyo Released 2010/01/14 Keywords: antiproton, CERN, fundamental physical constants, laser spectroscopy Full Text PDF [1604K] Abstracts References(25) Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN’s antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended val...

  17. Intensity-Frontier Antiproton Physics with The Antiproton Annihilation Spectrometer (TAPAS) at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Apollinari, Giorgio; /Fermilab; Asner, David M.; /PNL, Richland; Baldini, Wander; /INFN, Ferrara; Bartoszek, Larry; Broemmelsiek, Daniel R.; Brown, Charles N.; /Fermilab; Chakravorty, Alak; /St. Xavier U., Chicago; Colas, Paul; /Saclay; Derwent, Paul; /Fermilab; Drutskoy, Alexey; /Moscow, ITEP; Fortner, Michael; /Northern Illinois U. /Saclay /Indian Inst. Tech., Hyderabad

    2011-11-01

    The Fermilab Antiproton Source is the world's most intense source of antimatter. With the Tevatron program now behind us, this unique facility can help make the case for Fermilab's continued accelerator operations. The Antiproton Source can be used for unique, dedicated antimatter studies, including medium-energy {bar p}-annihilation experiments. We propose to assemble a powerful, yet cost-effective, solenoidal magnetic spectrometer for antiproton-annihilation events, and to use it at the Fermilab Antiproton Accumulator to measure the charm production cross section, study rare hyperon decays, search for hyperon CP asymmetry, precisely measure the properties of several charmonium and nearby states, and make the first measurements of the Drell-Yan continuum in medium-energy antiproton annihilation. Should the charm production cross section be as large as some have proposed, we will also be able to measure D{sup 0}-{bar D}{sup 0} mixing with high precision and discover (or sensitively limit) charm CP violation. The observation of charm or hyperon CP violation would be evidence for physics beyond the Standard Model, with possible implications for the origin of the baryon asymmetry of the universe - the question of what happened to all the antimatter that must have been produced in the Big Bang. The experiment will be carried out by an international collaboration and will require some four years of running time. As possibly the sole hadron experiment in progress at Fermilab during that time, it will play an important role in maintaining a broad particle physics program at Fermilab and in the U.S. It will thus help us to continue attracting creative and capable young people into science and technology, and introducing them to the important technologies of accelerators, detectors, and data acquisition and analysis - key roles in society that accelerator-based particle physics has historically played.

  18. Autoresonant Excitation of Antiproton Plasmas

    CERN Document Server

    Andresen, Gorm B; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D; Butler, Eoin; Carpenter, P T; Cesar, Claudio L; Chapman, Steven; Charlton, Michael; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C; Gill, David R; Hangst, Jeffrey S; Hardy, Walter N; Hayden, Michael E; Humphries, Andrew J; Hurt, J L; Hydomako, Richard; Jonsell, Svante; Madsen, Niels; Menary, Scott; Nolan, Paul; Olchanski, Konstantin; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Silveira, Daniel M; So, Chukman; Storey, James W; Thompson, Robert I; van der Werf, Dirk P; Wurtele, Jonathan S; Yamazaki, Yasunori

    2011-01-01

    We demonstrate controllable excitation of the center-of-mass longitudinal motion of a thermal antiproton plasma using a swept-frequency autoresonant drive. When the plasma is cold, dense, and highly collective in nature, we observe that the entire system behaves as a single-particle nonlinear oscillator, as predicted by a recent theory. In contrast, only a fraction of the antiprotons in a warm plasma can be similarly excited. Antihydrogen was produced and trapped by using this technique to drive antiprotons into a positron plasma, thereby initiating atomic recombination.

  19. A Measurement of Z Boson Production and Rapidity Distribution in Proton-Antiproton Collisions at √s = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Robson, Aidan [Univ. of Oxford (United Kingdom). Particle Physics Dept.

    2004-12-25

    High-precision measurements are made of Z boson production in proton-antiproton collisions at √s = 1.96 TeV recorded by the Collider Detector at Fermilab, using the electron decay channel. The cross-section times branching ratio is measured to be σZ · Br(Z → e+e-) = (255.7 ± 2.4stat ± 5.2sys ± 15.2lum)pb in a dataset of 194 pb-1 collected between March 2002 and June 2003. This agrees well with theoretical predictions. The cross-section for W boson production in the electron channel has also been measured in the subset of this dataset of 72 pb-1 collected up until January 2003. Using this smaller dataset the ratio of cross-sections is determined to be R ≡ σW · Br(W → eν)/σZ · Br(Z → ee) = 10.82 ± 0.18stat ± 0.16sys. Combining these results with measurements made in the muon channel gives R = 10.92 ± 0.15stat ± 0.14sys (e + μ channels), from which the branching ratio of the W to electrons and muons, and the total width of the W, have been extracted: Br(W → lν) = 0.1089 ± 0.0022 (l = e,μ); Γ(W) = 2078.8 ± 41.4 MeV, which are in good agreement with the Standard Model values and with other measurements. The CKM quark mixing matrix element |Vcs| has been extracted: |Vcs| = 0.967 ± 0.030. The rapidity distribution dσ/dy for Z → ee has also been measured over close to the full kinematic range using 194 pb-1 of data, and is found to be in good agreement with the NNLO prediction.

  20. Single and double ionization of helium by fast antiproton and proton impact

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Mo-dash-barller, S.P.; Elsener, K.; Rensfelt, K.H.; Uggerho-dash-barj, E.

    1986-10-27

    The first ion-atom--collision data obtained with antiprotons are presented. We measured the single- and double-ionization cross section for 0.5-5-MeV antiprotons and protons colliding with helium. For ion energies above --2 MeV, the single-ionization cross section is the same for protons and antiprotons. However, surprisingly, the double-ionization cross section for antiprotons is approximately a factor of 2 larger than that for protons. The present data constitute a challenge for future theoretical models of charged-particle--atom collisions.

  1. The Antiproton Accumulator (AA)

    CERN Multimedia

    1980-01-01

    Section 06 - 08*) of the AA where the dispersion (and hence the horizontal beam size) is large. One can distinguish (left to right): A vacuum-tank, two bending magnets (BST06 and BST07 in blue) with a quadrupole (QDN07, in red) in between, another vacuum-tank, a wide quadrupole (QFW08) and a further tank . The tanks are covered with heating tape for bake-out. The tank left of BST06 contained the stack core pickup for stochastic cooling (see 7906193, 7906190, 8005051), the two other tanks served mainly as vacuum chambers in the region where the beam was large. Peter Zettwoch works on BST06. *) see: H. Koziol, Antiproton Accumulator Parameter List, PS/AA/Note 84-2 (1984)

  2. Measurement of top anti-top cross section in proton - anti-proton collider at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Mal, Prolay Kumar [Tata Inst. of Fundamental Research, Bombay (India)

    2005-04-01

    Discovery of the top quark in 1995 at the Fermilab Tevatron collider concluded a long search following the 1977 discovery of bottom (b) quark [1] and represents another triumph of the Standard Model (SM) of elementary particles. Top quark is one of the fundamental fermions in the Standard Model of electroweak interactions and is the weak-isospin partner of the bottom quark. A precise measurement of top pair production cross-section would be a test of Quantum Chromodynamics (QCD) prediction. Presently, Tevatron is the world's highest energy collider where protons (p) and anti-protons ($\\bar{p}$) collide at a centre of mass energy √s of 1.96 TeV. At Tevatron top (t) and anti-top ($\\bar{t}$) quarks are predominantly pair produced through strong interactions--quark annihilation (≅ 85%) and gluon fusion (≅ 15%). Due to the large mass of top quark, t or $\\bar{t}$ decays (~ 10-25 sec) before hadronization and in SM framework, it decays to a W boson and a b quark with ~ 100% branching ratio (BR). The subsequent decay of W boson determines the major signatures of t$\\bar{t}$ decay. If both W bosons (coming from t and $\\bar{t}$ decays) decay into leptons (viz., eve, μvμ or τcτ) the corresponding t$\\bar{t}$ decay is called dileptonic decay. Of all dileptonic decay modes of t$\\bar{t}$, the t$\\bar{t}$ → WWb$\\bar{b}$ → eveμvμb$\\bar{b}$ (eμ channel) decay mode has the smallest background contamination from Z0 production or Drell-Yan process; simultaneously, it has the highest BR (~ 3.16%) [2] amongst all dileptonic decay modes of t$\\bar{t}$. During Run I (1992-1996) of Tevatron, three eμ candidate events were detected by D0 experiment, out of 80 candidate events (inclusive of all decay modes of t$\\bar{t}$). Due to the rarity of the t$\\bar{t}$ events, the measured cross-section has large uncertainty in its value (viz., 5.69 ± 1.21(stat) ± 1.04(sys) pb {at} √s = 1

  3. Antiproton Cancer Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels

    An essential part in cancer radiotherapy, is to direct a sufficiently high dose towards the tumour, without damaging the surrounding tissue. Different techniques such as intensity modulated radiation therapy and proton therapy have been developed, in order to reduce the dose to the normal tissue...

  4. Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon A Search for TeV-Energy Antiprotons

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, G J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kraber, M; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2005-01-01

    The shadowing of high-energy cosmic rays by the Moon has been observed with a significance of 9.4 standard deviations with the L3+C muon spectrometer at CERN. A significant effect of the Earth magnetic field is observed. Since no event deficit on the east side of the Moon has been observed, an upper limit at 90% confidence level on the antiproton to proton ratio of 0.11 is obtained for primary energies around 1 TeV.

  5. Measurement of the Cross Section for Production of Prompt Diphoton in proton anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan-wen [Univ. of Geneva (Switzerland)

    2004-01-01

    This thesis presents the measurement of prompt diphoton production rate in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV using the upgraded Collider Detector at Fermilab (CDF II). This process deserves some attention for the following reasons. The H → γγ decay mode is an important channel for the Standard Model (SM) Higgs boson searches in the low mass region (MH < 130 GeV) at the forth coming LHC. In many models involving physics beyond the SM, cascade decays of heavy new particles generate a γγ signature. Some examples are supersymmetry with a light gravitino, radiative decays to a higgsino-LSP and models with large symmetry groups. The QCD production of prompt photon pairs with large invariant mass is the irreducible background to these searches. The rate is huge and requires to be quantitatively evaluated prior to any of the possible discoveries. In a hadronic collider environment such as LHC, prompt photon signals are contaminated by the production of neutral mesons which decay to multiple collinear photons. The experience of classifying background of neutral meson is very important. The process can be used to test the Next-to-Leading Order (NLO) calculation of Quantum Chromodynamics (QCD). The 4-momentum of particles in the di-photon final state can be precisely determined due to the fine energy resolution of the electromagnetic calorimeters. The imbalance in the transverse momentum of the two photons reflects the transverse motion of the colliding partons. At collider energies, most of the transverse momentum of the incoming partons can be attributed to multiple soft gluon emissions prior to the collision, of which the effect to di-photon production can be resummed by Collins-Soper-Sterman (CSS) formalism. The Tevatron data can be used to test the resummation formalisms. They have used 207 pb-1 of data collected by CDF II detector during the February 2002 to September 2003 running period to study the diphoton

  6. Measurement of the Cross Section for Production of Prompt Diphoton in proton anti-proton Collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan-wen

    2004-11-01

    This thesis presents the measurement of prompt diphoton production rate in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV using the upgraded Collider Detector at Fermilab (CDF II). This process deserves some attention for the following reasons. The H {yields} {gamma}{gamma} decay mode is an important channel for the Standard Model (SM) Higgs boson searches in the low mass region (M{sub H} < 130 GeV) at the forth coming LHC. In many models involving physics beyond the SM, cascade decays of heavy new particles generate a {gamma}{gamma} signature. Some examples are supersymmetry with a light gravitino, radiative decays to a higgsino-LSP and models with large symmetry groups. The QCD production of prompt photon pairs with large invariant mass is the irreducible background to these searches. The rate is huge and requires to be quantitatively evaluated prior to any of the possible discoveries. In a hadronic collider environment such as LHC, prompt photon signals are contaminated by the production of neutral mesons which decay to multiple collinear photons. The experience of classifying background of neutral meson is very important. The process can be used to test the Next-to-Leading Order (NLO) calculation of Quantum Chromodynamics (QCD). The 4-momentum of particles in the di-photon final state can be precisely determined due to the fine energy resolution of the electromagnetic calorimeters. The imbalance in the transverse momentum of the two photons reflects the transverse motion of the colliding partons. At collider energies, most of the transverse momentum of the incoming partons can be attributed to multiple soft gluon emissions prior to the collision, of which the effect to di-photon production can be resummed by Collins-Soper-Sterman (CSS) formalism. The Tevatron data can be used to test the resummation formalisms. They have used 207 pb{sup -1} of data collected by CDF II detector during the February 2002 to September 2003 running period to

  7. Measurement of the Single Top Quark Production Cross Section in 1.96-TeV Proton-Antiproton Collisions

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Koji [Univ. of Tsukuba (Japan)

    2009-02-01

    Top quarks are predominantly produced in pairs via the strong interaction in $\\bar{p}$p collisions at √s = 1.96 TeV . The top quark has a weak isospin 1/2, composing a weak isospin doublet with the bottom quark. This characteristic predicts not only top quark pair production via strong interaction but also single production together with a bottom quark via weak interaction. However, finding single top quark production is challenging since it is rarely produced (σ singletop = 2.9 pb) against background processes with the same final state like W+jets and t$\\bar{t}$. A measurement of electroweak single top production probes the W-t-b vertex, which provides a direct determination of the Cabbibo-Kobayashi-Maskawa (CKM) matrix element |Vtb|. The sample offers a source of almost 100% polarized top quarks. This thesis describes an optimized search for s-channel single top quark production and a measurement of the single top production cross section using 2.7 fb-1 of data accumulated with the CDF detector. We are using events with one high-pT lepton, large missing ET and two identified b-quark jets where one jet is identified using a secondary vertex tagger, called SecVtx, and the other jet is identified using SecVtx or a jet probability tagger, called JetProb. In this analysis we have developed a kinematics fitter and a likelihood-based separator between signal and background. As a result, we found that the probability (p-value) that the candidate events originate from a background fluctuation in the absence of single top s-channel production is 0.003, which is equivalent to 2.7 σ deviations in Gaussian statistics, and this excess corresponds to the single top s-channel cross section of 2.38-0.84+1.01 pb. An observed value of |Vtb| is 1.43-0.26+0.38(experimental) ± 0.11(theory). We also set the 95% CL. upper limit of σs = 4.15 pb for the s

  8. Antiprotonic atom formation and spectroscopy-ASACUSA experiment at CERN-AD

    CERN Document Server

    Widmann, E

    1999-01-01

    This talk describes the experiments on atomic spectroscopy and atomic collisions as proposed by the ASACUSA collaboration for the forthcoming AD facility at CERN. They consist of high-precision spectroscopy of antiprotonic atoms, the study of anti-protonic atom formation processes, and stopping power and ionization measurements in low-pressure gases. (18 refs).

  9. Measurement of the resonance parameters of the chi(1)(1**3P(1)) and chi(2)(1**3P(2)) states of charmonium formed in antiproton-proton annihilations

    Energy Technology Data Exchange (ETDEWEB)

    Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A.; Calabrese, R.; Cester, R.; Cibinetto, G.; Dalpiaz, P.; Garzoglio, G.; Gollwitzer, K.E.; Graham, M.; Hu, M.; Joffe, D.; Kasper, J.; Lasio, G.; Lo Vetere, M.; Luppi, E.; Macri, M.; Mandelkern, M.; /Fermilab /INFN, Ferrara /Ferrara U. /INFN, Genoa /Genoa U. /UC, Irvine

    2005-03-01

    The authors have studied the {sup 3}P{sub J} ({chi}{sub e}) states of charmonium in formation by antiproton-proton annihilations in experiment E835 at the Fermilab Antiproton Source. The authors report new measurements of the mass, width, and B({chi}{sub cJ} {yields} {bar p}p) x {Lambda}({chi}{sub eJ} {yields} J/{psi} + anything) for the {chi}{sub c1} and {chi}{sub c2} by means of the inclusive reaction {bar p}p {yields} {chi}{sub cJ} {yields} J/{psi} + anything {yields} (e{sup +}e{sup -}) + anything. Using the subsample of events where {chi}{sub cJ} {yields} {gamma} + J/{psi} {yields} {gamma} + (e{sup +}e{sup -}) is fully reconstructed, we derive B({chi}{sub cJ} {yields} {bar p}p) x {Lambda}({chi}{sub cJ} {yields} J/{psi} + {gamma}). They summarize the results of the E760 (updated) and E835 measurements of mass, width and B({chi}{sub cJ} {yields} {bar p}p){Lambda}({chi}{sub cJ} {yields} J/{psi} + {gamma}) (J = 0,1,2) and discuss the significance of these measurements.

  10. The Antiproton Accumulator (AA)

    CERN Multimedia

    1980-01-01

    A section of the AA where the dispersion (and hence the horizontal beam size) is large. One can distinguish (left to right): A large vacuum-tank, a quadrupole (QDN09*), a bending magnet (BST08), another vacuum-tank, a wide quadrupole (QFW08) and (in the background) a further bending magnet (BST08). The tanks are covered with heating tape for bake-out. The tank left of QDN09 contained the kickers for stochastic pre-cooling (see 790621, 8002234, 8002637X), the other one served mainly as vacuum chamber in the region where the beam was large. Peter Zettwoch works on QFW08. * see: H. Koziol, Antiproton Accumulator Parameter List, PS/AA/Note 84-2 (1984) See under 7911303, 7911597X, 8004261 and 8202324. For photos of the AA in different phases of completion (between 1979 and 1982) see: 7911303, 7911597X, 8004261, 8004608X, 8005563X, 8005565X, 8006716X, 8006722X, 8010939X, 8010941X, 8202324, 8202658X, 8203628X .

  11. Low Energy Antiproton Ring experimental area

    CERN Multimedia

    1991-01-01

    The experimental area at the Low Energy Antiproton Ring (LEAR) is seen. This set up was used to slow down antiprotons which had been produced by colliding a proton beam with a solid target. The experiments in the hall then took antiprotons from LEAR to perform antimatter studies. One such experiment, PS210, produced the world's first antihydrogen atoms.

  12. GEANT4 simulation of the ACE beam line : Measurement of the energy distribution of degraded Antiproton beam and the ToF signal of generated pions.

    CERN Document Server

    BRAHIMI, Nihel

    2014-01-01

    The present document describes my 8 weeks work project as a summer student at the AEgIS experiment under the supervision of Michael Doser and what i have learned during this period . It can be devided into three main tasks which are: Theoretical preparations concerning low energy antiproton physics. Learning the basic principles of GEANT4 simu- lation toolkit. Using GEANT4 platform to follow up the work of two technical students (Logan and Conrad) in designing an experiment (ACE beam line ) which aims at improving the methods of detect- ing matter-antimatter annihilations vertices at low energies in terms of resolution and accuracy using hybrid detectors .

  13. Measurement of the top quark pair production cross-section in dimuon final states in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Konrath, Jens Peter [Albert Ludwigs Univ., Freiburg (Germany)

    2008-10-24

    Particle physics deals with the fundamental building blocks of matter and their interactions. The vast number of subatomic particles can be reduced to twelve fundamental fermions, which interact by the exchange of spin-1 particles as described in the Standard Model (SM) of particle physics. The SM provides the best description of the subatomic world to date, despite the fact it does not include gravitation. Following the relation Λ = h/p, where h is Planck's constant, for the examination of physics at subatomic scales with size Λ probes with high momenta p are necessary. These high energies are accessible through particle colliders. Here, particles are accelerated and brought to collision at interaction points at which detectors are installed to record these particle collisions. Until the anticipated start-up of the Large Hadron Collider at CERN, the Tevatron collider at Fermilab near Chicago is the highest energy collider operating in the world, colliding protons and anti-protons at a center-of-mass energy of √s = 1.96 TeV. Its two interaction points are covered by the multi purpose particle detectors D0 and CDF. During the first data-taking period, known as Run I, the Tevatron operated at a center-of-mass energy of 1.8 TeV. This run period lasted from 1992 to 1996. During this period, the long-predicted top quark was discovered. From 1996 and 2001, the accelerator was upgraded to deliver higher instantaneous luminosities at its current center-of-mass energy. At the same time, the experiments were upgraded to take full advantage of the upgraded accelerator complex. The Tevatron is currently the only accelerator in the world with a sufficient energy to produce top quarks. Studying top quark production, decay and properties is an important part of the D0 and CDF physics programs. Because of its large mass, the top quark is a unique probe of the Standard Model, and an interesting environment to search for new physics. In this thesis, a measurement of the

  14. Nuclear dynamics induced by antiprotons

    CERN Document Server

    Feng, Zhao-Qing

    2015-01-01

    Reaction dynamics in collisions of antiprotons on nuclei is investigated within the Lanzhou quantum molecular dynamics model. The reaction channels of elastic scattering, annihilation, charge exchange and inelastic collisions of antiprotons on nucleons have been included in the model. Dynamics on particle production, in particular pions, kaons, antikaons and hyperons, is investigated in collisions of $\\overline{p}$ on $^{12}$C, $^{20}$Ne, $^{40}$Ca and $^{181}$Ta from a low to high incident momenta. It is found that the annihilations of $\\overline{p}$ on nucleons are of importance on the dynamics of particle production in phase space. Hyperons are mainly produced via meson induced reactions on nucleons and strangeness exchange collisions, which lead to the delayed emission in antiproton-nucleus collisions.

  15. Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb–Pb collisions at √(s{sub NN})=2.76 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abelev, B. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Adam, J. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague (Czech Republic); Adamová, D. [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Řež u Prahy (Czech Republic); Adare, A.M. [Yale University, New Haven, CT (United States); Aggarwal, M.M. [Physics Department, Panjab University, Chandigarh (India); Aglieri Rinella, G. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Agocs, A.G. [KFKI Research Institute for Particle and Nuclear Physics, Hungarian Academy of Sciences, Budapest (Hungary); Agostinelli, A. [Dipartimento di Fisica dell' Università and Sezione INFN, Bologna (Italy); Aguilar Salazar, S. [Instituto de Física, Universidad Nacional Autónoma de México, Mexico City (Mexico); Ahammed, Z. [Variable Energy Cyclotron Centre, Kolkata (India); Ahmad Masoodi, A.; Ahmad, N. [Department of Physics, Aligarh Muslim University, Aligarh (India); Ahn, S.U. [Gangneung-Wonju National University, Gangneung (Korea, Republic of); Akindinov, A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Aleksandrov, D. [Russian Research Centre Kurchatov Institute, Moscow (Russian Federation); Alessandro, B. [Sezione INFN, Turin (Italy); Alfaro Molina, R. [Instituto de Física, Universidad Nacional Autónoma de México, Mexico City (Mexico); Alici, A. [Centro Fermi – Centro Studi e Ricerche e Museo Storico della Fisica “Enrico Fermi”, Rome (Italy); Alkin, A. [Bogolyubov Institute for Theoretical Physics, Kiev (Ukraine); and others

    2013-02-12

    The elliptic, v{sub 2}, triangular, v{sub 3}, and quadrangular, v{sub 4}, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions, and (anti-)protons in Pb–Pb collisions at √(s{sub NN})=2.76 TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range |η|<0.8 at different collision centralities and as a function of transverse momentum, p{sub T}, out to p{sub T}=20 GeV/c. The observed non-zero elliptic and triangular flow depends only weakly on transverse momentum for p{sub T}>8 GeV/c. The small p{sub T} dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to p{sub T}=8 GeV/c. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least p{sub T}=8 GeV/c indicating that the particle type dependence persists out to high p{sub T}.

  16. Antiproton collisions with molecular hydrogen

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2008-01-01

    Theoretical antiproton and proton cross sections for ionization and excitation of hydrogen molecules as well as energy spectra of the ionized electrons were calculated in the impact-energy range from 8  to  4000  keV. The cross sections were computed with the close-coupling formulation of the sem......Theoretical antiproton and proton cross sections for ionization and excitation of hydrogen molecules as well as energy spectra of the ionized electrons were calculated in the impact-energy range from 8  to  4000  keV. The cross sections were computed with the close-coupling formulation...

  17. Optimizing a three-stage Compton camera for measuring prompt gamma rays emitted during proton radiotherapy.

    Science.gov (United States)

    Peterson, S W; Robertson, D; Polf, J

    2010-11-21

    In this work, we investigate the use of a three-stage Compton camera to measure secondary prompt gamma rays emitted from patients treated with proton beam radiotherapy. The purpose of this study was (1) to develop an optimal three-stage Compton camera specifically designed to measure prompt gamma rays emitted from tissue and (2) to determine the feasibility of using this optimized Compton camera design to measure and image prompt gamma rays emitted during proton beam irradiation. The three-stage Compton camera was modeled in Geant4 as three high-purity germanium detector stages arranged in parallel-plane geometry. Initially, an isotropic gamma source ranging from 0 to 15 MeV was used to determine lateral width and thickness of the detector stages that provided the optimal detection efficiency. Then, the gamma source was replaced by a proton beam irradiating a tissue phantom to calculate the overall efficiency of the optimized camera for detecting emitted prompt gammas. The overall calculated efficiencies varied from ∼ 10(-6) to 10(-3) prompt gammas detected per proton incident on the tissue phantom for several variations of the optimal camera design studied. Based on the overall efficiency results, we believe it feasible that a three-stage Compton camera could detect a sufficient number of prompt gammas to allow measurement and imaging of prompt gamma emission during proton radiotherapy.

  18. Many Facets of Strangeness Nuclear Physics with Stored Antiprotons

    CERN Document Server

    Pochodzalla, Josef; Lorente, Alicia Sanchez; Rojo, Marta Martinez; Steinen, Marcell; Gerl, Jürgen; Kojouharova, Jasmina; Kojouharova, Ivan

    2016-01-01

    Stored antiprotons beams in the GeV range represent a unparalleled factory for hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of strange hadronic systems with unprecedented precision. The behavior of hyperons and -- for the first time -- of antihyperons in nuclear systems can be studied under well controlled conditions. The exclusive production of $\\Lambda\\bar{\\Lambda}$ and $\\Sigma^-\\bar{\\Lambda}$ pairs in antiproton-nucleus interactions probe the neutron and proton distribution in the nuclear periphery and will help to sample the neutron skin. For the first time, high resolution $\\gamma$-spectroscopy of doubly strange nuclei will be performed, thus complementing measurements of ground state decays of double hypernuclei with mesons beams at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange $\\Xi$-atoms are feasible and even the pr...

  19. Strangeness production in antiproton nucleus interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.; Bonner, B.E. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.; Buchanan, J.A. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.; Carter, P. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.; Chan, C.S.; Clement, J.M.; Eiseman, S.E.; Empl, A.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Hallman, T.J.; Kramer, M.A.; Lindenbaum, S.J.; Longacre, R.S.; Love, W.A.; Madansky, L.; Mattingly, A.C.; Morris, T.W.; Mutchler, G.S.; Peaslee, D.C.; Platner, E.D.; Saulys, A.C.; Toshkov, S.

    1997-06-01

    Results on the measurement of inclusive K{sub S}{sup 0}, {Lambda} and {Lambda} production cross sections and rapidity distributions for antiproton interactions on lead, copper and carbon nuclear targets at beam momenta of 5.2, 7.0 and 8.8 GeV/c are reported. Simulations employing a conventional intra-nuclear cascade model were able to reproduce the experimental results. Hence, no compelling evidence for the formation of exotic quark-gluon states of matter was found. (orig.).

  20. Measurement of the Forward-Backward Charge Asymmetry of Electron-Positron Pairs in Proton anti-Proton Collisions at s**(1/2)=1.96-TeV

    CERN Document Server

    Acosta, D; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bölla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Bromberg, C; Brubaker, E; Budagov, Yu A; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Calafiura, P; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerri, C; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chu, M L; Chuang, S; Chung, J Y; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas-Maestro, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; De Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'Agnello, S; Dell'Orso, Mauro; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Feild, R G; Feindt, M; Fernández, J P; Ferretti, C; Field, R D; Fiori, I; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J; Frisch, H; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; García-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gómez, G; Gómez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Yu; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Günther, M; Guimarães da Costa, J; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Höcker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J R; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S; Junk, T R; Kamon, T; Kang, J; Karagoz-Unel, M; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A J; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kuznetsova, N; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; LeCompte, T; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P F; Lu, R S; Lucchesi, D; Lujan, P; Lukens, P; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Martin, M; Martin, A; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; NcNulty, R; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Mukherjee, A; Mulhearn, M; Müller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D V; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nicollerat, A S; Nigmanov, T; Nodulman, L; Norniella, O; Österberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R G C; Orava, R; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, Aldo L; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Plager, C; Pompos, A; Pondrom, L; Pope, G; Poukhov, O; Prakoshyn, F; Pratt, T; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Rademacker, J; Rakitine, A; Rappoccio, S; Ratnikov, F; Ray, H; Reichold, A; Reisert, B; Rekovic, V; Renton, P B; Rescigno, M; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Russ, J; Ruiz, A; Ryan, D; Saarikko, H; Safonov, A; Saint-Denis, R; Sakumoto, W K; Salamanna, G; Saltzberg, D; Sánchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Schemitz, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T G; Shepard, P F; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Siegrist, J; Siket, M; Sill, A; Sinervo, P; Sissakian, A N; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Somalwar, S V; Spalding, J; Spezziga, M; Spiegel, L; Spinella, F; Spiropulu, M; Squillacioti, P; Stadie, H; Stefanini, A; Stelzer, B; Stelzer-Chilton, O; Strologas, J; Stuart, D; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A C; Tafirout, R; Takach, S F; Takano, H; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tapprogge, Stefan; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tollefson, K; Tomura, T; Tonelli, D; Tonnesmann, M; Torre, S; Torretta, D; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Tsybychev, D; Turini, N; Turner, M; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A W; Varganov, A; Vataga, E; Vejcik, S; Velev, G V; Veramendi, G; Vickey, T; Vidal, R; Vila, I; Vilar, R; Volobuev, I P; Von der Mey, M; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Yamashita, T; Yamamoto, K; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolter, M; Worcester, M; Worm, S; Wright, T; Wu, X; Würthwein, F; Wyatt, A; Yagil, A; Yang, U K; Yao, W; Yeh, G P; Yi, K; Yoh, J; Yoon, P; Yorita, K; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhou, J; Zsenei, A; Zucchelli, S

    2004-01-01

    We present a measurement of the mass dependence of the forward-backward charge asymmetry (A_{FB}) for electron-positron pairs produced via an intermediate Z/gamma with mass Mee > 40 GeV/c**(2). We study the constraints on the Z-quark couplings imposed by our measurement. We analyze an integrated luminosity of 72 pb-1 collected by the CDF II detector in proton anti-proton collisions at s**(1/2) = 1.96 TeV at the Fermilab Tevatron. A comparison of the uncorrected A_{FB} between data and Standard Model Monte Carlo gives good agreement with a chi^2/DOF of 15.7/15. The couplings measurements are also consistent with Standard Model predictions.

  1. An intercomparison of neutron measurments for a 25 MV x-ray radiotherapy accelerator.

    Science.gov (United States)

    Nath, R; Price, K W; Holeman, G R

    1980-01-01

    High-energy x-ray radiotherapy machines produce neutrons by photonuclear reactions which present a potential radiation hazard to the personnel and patient. A series of measurements of the neutron flux from a 25 MV x-ray linear accelerator, inside and outside the treatment room, have been performed using a multisphere spectrometer, Nemo dosimeter, and activation detectors. These results are compared with other mixed photon-neutron field measurements for the same machine performed using an argon/propane ionization chamber, silicon diode, track-etching detectors, and Monte Carlo calculations. It is found that these measurements agree with each other within a factor of two except for silicon diode measurements in the photon beam. Measured neutron spectra at various locations in the treatment room are also compared with the results of Monte Carlo transport calculations.

  2. High-energy antiprotons from old supernova remnants

    CERN Document Server

    Blasi, Pasquale

    2009-01-01

    A recently proposed model (arXiv:0903.2794) explains the rise in energy of the positron fraction measured by the PAMELA satellite in terms of hadronic production of positrons in aged supernova remnants, and acceleration therein. Here we present a preliminary calculation of the anti-proton flux produced by the same mechanism. While the model is consistent with present data, a rise of the antiproton to proton ratio is predicted at high energy, which strikingly distinguishes this scenario from other astrophysical explanations of the positron fraction (like pulsars). We briefly discuss important implications for Dark Matter searches via antimatter.

  3. High-energy antiprotons from old supernova remnants.

    Science.gov (United States)

    Blasi, Pasquale; Serpico, Pasquale D

    2009-08-21

    A recently proposed model explains the rise in energy of the positron fraction measured by the PAMELA satellite in terms of hadronic production of positrons in aged supernova remnants, and acceleration therein. Here we present a preliminary calculation of the antiproton flux produced by the same mechanism. While the model is consistent with present data, a rise of the antiproton to proton ratio is predicted at high energy, which strikingly distinguishes this scenario from other astrophysical explanations of the positron fraction (such as pulsars). We briefly discuss important implications for dark matter searches via antimatter.

  4. Development of narrowband lasers for spectroscopy of antiprotonic atoms

    Directory of Open Access Journals (Sweden)

    Hori M.

    2014-03-01

    Full Text Available We review some lasers developed by the ASACUSA collaboration of CERN, to carry out spectroscopy of antiprotonic helium atoms. These lasers were based on the technique of continuous-wave injection seeding of pulsed lasers. The laser output covered the wavelength regions 264–1154 nm, with peak powers of ~ 1 MW and spectral resolutions of 6–40 MHz. The devices were recently used to measure the transition frequencies of antiprotonic helium atoms to a fractional precision of several parts in ~ 109.

  5. LEAR (Low Energy Antiproton Ring), general view.

    CERN Multimedia

    1990-01-01

    When the Antiproton Project was launched in the late 1970s, it was recognized that in addition to the primary purpose of high-energy proton-antiproton collisions in the SPS, there was interesting physics to be done with low-energy antiprotons. In 1982, LEAR was ready to receive antiprotons from the Antiproton Accumulator (AA), via the PS. A year later, delivery of antiprotons to the experiments began, at momenta as low as 100 MeV/c (kinetic energy 5.3 MeV), in an "Ultra-Slow Extraction" mode, dispensing some E9 antiprotons over times counted in hours. For such an achievement, stochastic and electron cooling had to be brought to high levels of perfection.

  6. Capture, Electron-Cooling and Compression of Antiprotons in a Large Penning-Trap for Physics Experiments with an Ultra-Low Energy Extracted Antiproton Beam

    CERN Multimedia

    2002-01-01

    % PS200 \\\\ \\\\The availability of ultra-low energy antiprotons is a crucial ingredient for the execution of the gravity measurements PS200. We have developed a method to provide such low energy antiprotons based on a large Penning trap (the PS200 catching trap). This system can accept a fast-extracted pulse from LEAR, reduce the energy of the antiprotons in the pulse from 5.9~MeV to several tens of kilovolts using a degrading foil, and then capture the antiprotons in a large Penning trap. These antiprotons are cooled by electrons previously admitted to the trap and are collected in a small region at the center of the trap. We have demonstrated our capability to capture up to 1~million antiprotons from LEAR in a single shot, electron cool these antiprotons, and transfer up to 95\\% of them into the inner, harmonic region. A storage time in excess of 1 hour was observed. These results have been obtained with the cryogenic trap vacuum coupled to a room temperature vacuum at about l0$ ^- ^{1} ^0 $ Torr, which is an...

  7. Selenium supplementation in radiotherapy patients: do we need to measure selenium levels in serum or blood regularly prior radiotherapy?

    Science.gov (United States)

    Muecke, Ralph; Micke, Oliver; Schomburg, Lutz; Kisters, Klaus; Buentzel, Jens; Huebner, Jutta; Kriz, Jan

    2014-12-16

    Considering the review by Puspitasari and colleagues, an additional discussion of the endpoints of the Se supplementation studies described would be helpful. In our view, selenium can safely be given to selenium-deficient cancer patients prior to and during radiotherapy. Therefore, in order to help the radiation oncologist in decision making, we strongly advocate to determine the selenium status prior to and during a potential adjuvant selenium supplementation, e.g. when trying to ease the side-effects of radiation treatment or in the aftercare situation when the selenium status may become insufficient.

  8. Energy and centrality dependence of antiproton and proton production in relativistic Pb+Pb collisions at the CERN SPS

    CERN Document Server

    Alt, C; Baatar, B.; Barna, D.; Bartke, J.; Betev, L.; Bialkowska, H.; Blume, C.; Boimska, B.; Botje, M.; Bracinik, J.; Bramm, R.; Buncic, P.; Cerny, V.; Christakoglou, P.; Chvala, O.; Cramer, J.G.; Csato, P.; Dinkelaker, P.; Eckardt, V.; Flierl, D.; Fodor, Z.; Foka, P.; Friese, V.; Gal, J.; Gazdzicki, M.; Genchev, V.; Georgopoulos, G.; Gladysz, E.; Grebieszkow, K.; Hegyi, S.; Hohne, C.; Kadija, K.; Karev, A.; Kliemant, M.; Kniege, S.; Kolesnikov, V.I.; Kornas, E.; Korus, R.; Kowalski, M.; Kraus, I.; Kreps, M.; Laslo, A.; van Leeuwen, M.; Levai, P.; Litov, L.; Lungwitz, B.; Makariev, M.; Malakhov, A.I.; Mateev, M.; Melkumov, G.L.; Mischke, A.; Mitrovski, M.; Molnar, J.; Mrowczynski, St.; Nicolic, V.; Palla, G.; Panagiotou, A.D.; Panayotov, D.; Petridis, A.; Pikna, M.; Prindle, D.; Puhlhofer, F.; Renfordt, R.; Roland, C.; Roland, G.; Rybczynski, M.; Rybicki, A.; Sandoval, A.; Schmitz, N.; Schuster, T.; Seyboth, P.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Stefanek, G.; Stock, R.; Strabel, C.; Strobele, H.; Susa, T.; Szentpetery, I.; Sziklai, J.; Szymanski, P.; Trubnikov, V.; Varga, D.; Vassiliou, M.; Veres, G.I.; Vesztergombi, G.; Vranic, D.; Wetzler, A.; Wlodarczyk, Z.; Yoo, I.K.; Zimanyi, J.

    2005-01-01

    The transverse mass distributions for antiprotons are measured at midrapidity for minimum bias Pb+Pb collisions at 158A GeV and for central Pb+Pb collisions at 20, 30, 40 and 80 A GeV beam energies in the NA49 experiment at the CERN SPS. The rapidity density, inverse slope parameter and mean transverse mass derived from the transverse mass distributions are studied as a function of the incident energy and the collision centrality and compared to the relevant proton data. The shapes of the m_T distributions of antiprotons and protons are very similar. The ratios of the particle yields, antiproton/proton and antilambda/antiproton, are also analysed. The antiproton/proton ratio exhibits an increase with diminishing centrality and a steep rise with increasing beam energy. The antilambda/antiproton ratio increases beyond unity with decreasing beam energy.

  9. Antiproton annihilation physics annihilation physics in the Monte Carlo particle transport code particle transport code SHIELD-HIT12A

    DEFF Research Database (Denmark)

    Taasti, Vicki Trier; Knudsen, Helge; Holzscheiter, Michael

    2015-01-01

    The Monte Carlo particle transport code SHIELD-HIT12A is designed to simulate therapeutic beams for cancer radiotherapy with fast ions. SHIELD-HIT12A allows creation of antiproton beam kernels for the treatment planning system TRiP98, but first it must be benchmarked against experimental data...

  10. Measurement Of The Ratio Of Inclusive Cross Sections Of (proton-antiproton Decaying To Z Boson + Bottom- Jet)/(proton-antiproton Decaying To Z Boson + Jet) At Center Of Mass Energy = 1.96 Tev

    CERN Document Server

    Mutaf, Y D

    2005-01-01

    Using the data collected with the DØ detector at s = 1.96 TeV with integrated luminosities of about 180 pb−1 , we have measured the ratio of inclusive cross sections for pp¯ → Z + b-jet to pp¯ → Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider and is sensitive to the b quark content of the proton. This thesis describes our measurement which is performed using the dimuon decay channel of the Z boson, i.e., Z → μ+μ−. The ratio in the dimuon channel is measured to be 1.86 ± 0.44 (stat) +0.24-0.28 (syst)% for hadronic jets with transverse momenta pT > 20 GeV/c and pseudorapidities |η| < 2.5, consistent with next- to-leading order predictions of the standard model. This measurement is also combined with the result of the same ratio using the dielectron decay of the Z ...

  11. Cosmic ray antiprotons at high energies

    Science.gov (United States)

    Winkler, Martin Wolfgang

    2017-02-01

    Cosmic ray antiprotons provide a powerful tool to probe dark matter annihilations in our galaxy. The sensitivity of this important channel is, however, diluted by sizable uncertainties in the secondary antiproton background. In this work, we improve the calculation of secondary antiproton production with a particular focus on the high energy regime. We employ the most recent collider data and identify a substantial increase of antiproton cross sections with energy. This increase is driven by the violation of Feynman scaling as well as by an enhanced strange hyperon production. The updated antiproton production cross sections are made publicly available for independent use in cosmic ray studies. In addition, we provide the correlation matrix of cross section uncertainties for the AMS-02 experiment. At high energies, the new cross sections improve the compatibility of the AMS-02 data with a pure secondary origin of antiprotons in cosmic rays.

  12. Laser Spectroscopy of Antiprotonic Helium Atoms

    CERN Multimedia

    2002-01-01

    %PS205 %title\\\\ \\\\Following the discovery of metastable antiprotonic helium atoms ($\\overline{p}He^{+} $) at KEK in 1991, systematic studies of their properties were made at LEAR from 1991 to 1996. In the first two years the lifetime of $\\overline{p}He^{+}$ in liquid and gaseous helium at various temperatures and pressures was measured and the effect of foreign gases on the lifetime of these atoms was investigated. Effects were also discovered which gave the antiproton a 14\\% longer lifetime in $^4$He than in $^3$He, and resulted in important differences in the shape of the annihilation time spectra in the two isotopes.\\\\ \\\\Since 1993 laser spectroscopy of the metastable $\\overline{p}He^{+}$ atoms became the main focus of PS205. Transitions were stimulated between metastable and non-metastable states of the $\\overline{p}He^{+}$ atom by firing a pulsed dye laser beam into the helium target every time an identified metastable atom was present (Figure 1). If the laser frequency matched the transition energy, the...

  13. PS, septum magnet for ejection of antiprotons

    CERN Multimedia

    1980-01-01

    Antiprotons circulated in the PS in the sense opposite to that of the so far normal protons (or positive ions). A new ejection system with a new septum magnet was installed in straight section 58 for antiproton ejection, first towards the ISR and then to the principal customer, the SPS p-pbar Collider. Later on, when the PS delivered leptons for LEP, the antiproton ejection system was use for the ejection of electrons.

  14. Measurements of Dose Distribution outside the Treatment Area in case of Radiotherapy Treatment using Polystyrene Phantom

    CERN Document Server

    Ahmed, Md Farid; Ahmed, G U; Miah, F K

    2012-01-01

    Dose distribution (depthwise and laterally) to organs outside the radiotherapy treatment field can be significant and therefore is of clinical interest from the radiation protection point of view. In the present work, measurements were performed in a locally fabricated polystyrene phantom using TLD chips (LiF-100) for different teletherapy units (Cobalt-60 gamma ray, 120 kVp X-ray and 250 kVp X-ray) to estimate the dose distribution at distances up to 40 cm from the field edge along the central axes of the field size. Finally, the dose distribution for Cobalt-60 beam energy is parameterized as a function of depth, distance from field edge, and field size and shape.

  15. Role of perfusion SPECT in prediction and measurement of pulmonary complications after radiotherapy for lung cancer

    DEFF Research Database (Denmark)

    Farr, Katherina P; Kramer, Stine; Khalil, Azza A

    2015-01-01

    radiotherapy (RT) for non-small-cell lung cancer (NSCLC). METHODS: Patients with NSCLC undergoing curative RT were included prospectively. Perfusion SPECT/CT and global pulmonary function tests (PFT) were performed before RT and four times during follow-up. Functional activity on SPECT was measured using...... a semiquantitative perfusion DS. Pulmonary morbidity was graded by the National Cancer Institute's Common Terminology Criteria for Adverse Events version 4 for pneumonitis. Patients were divided into two groups according to the severity of RP. RESULTS: A total of 71 consecutive patients were included in the study....... Baseline DS was associated with chronic obstructive pulmonary disease. A significant inverse correlation was found between baseline DS and forced expiratory volume in 1 s and diffusing capacity of the lung for carbon monoxide. Patients with severe RP had significantly higher baseline total lung DS (mean 5...

  16. Primary populations of metastable antiprotonic $^{4}He$ and $^{3}He$ atoms

    CERN Document Server

    Hori, Masaki; Hayano, R S; Ishikawa, T; Sakuguchi, J; Tasaki, T; Widmann, E; Yamaguchi, H; Torii, H A; Juhász, B; Horváth, D; Yamazaki, T

    2002-01-01

    Initial population distributions of metastable antiprotonic **4He and **3He atoms over principal and angular momentum quantum numbers were investigated using laser spectroscopy. The total fractions of antiprotons captured into the metastable states of the atoms were deduced. Cascade calculations were performed using the measure populations to reproduce the delayed annihilation time spectrum. Results showed agreement between the simulated and measured spectra. (Edited abstract) 30 Refs.

  17. Measurement of Thyroid Dose by TLD arising from Radiotherapy of Breast Cancer Patients from Supraclavicular Field

    Directory of Open Access Journals (Sweden)

    Farhood B.

    2016-06-01

    Full Text Available Background: Breast cancer is the most frequently diagnosed cancer and the leading global cause of cancer death among women worldwide. Radiotherapy plays a significant role in treatment of breast cancer and reduces locoregional recurrence and eventually improves survival. The treatment fields applied for breast cancer treatment include: tangential, axillary, supraclavicular and internal mammary fields. Objective: In the present study, due to the presence of sensitive organ such as thyroid inside the supraclavicular field, thyroid dose and its effective factors were investigated. Materials and Methods: Thyroid dose of 31 female patients of breast cancer with involved supraclavicular lymph nodes which had undergone radiotherapy were measured. For each patient, three TLD-100 chips were placed on their thyroid gland surface, and thyroid doses of patients were measured. The variables of the study include shield shape, the time of patient’s setup, the technologists’ experience and qualification. Finally, the results were analyzed by ANOVA test using SPSS 11.5 software. Results: The average age of the patients was 46±10 years. The average of thyroid dose of the patients was 140±45 mGy (ranged 288.2 and 80.8 in single fraction. There was a significant relationship between the thyroid dose and shield shape. There was also a significant relationship between the thyroid dose and the patient’s setup time. Conclusion: Beside organ at risk such as thyroid which is in the supraclavicular field, thyroid dose possibility should be reduced. For solving this problem, an appropriate shield shape, the appropriate time of the patient’s setup, etc. could be considered.

  18. A silicon multiplicity detector system for an experiment on the interaction of antiprotons with nuclei at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.; Bonner, B.E.; Buchanan, J.A.; Clement, J.M.; Empl, A.; Mutchler, G.S.; Toshkov, S. (Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.); Eiseman, S.E.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C. (Brookhaven National Lab., Upton, NY (United States)); Chan, C.S.; Kramer, M.A.; Lindenbaum, S.J. (City Coll., New York, NY (Unit

    1991-01-01

    A Large Angle Multiplicity Detector (LAMD) system has been developed and used at the BNL experiment E854: Antiproton Nucleus Interactions. This system performed well with an energetic antiproton beam. Charged particle multiplicity distributions from pbar annihilations were measured. We discuss the design and performance of the LAMD system in this paper. 6 refs., 10 figs.

  19. A silicon multiplicity detector system for an experiment on the interaction of antiprotons with nuclei at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.; Bonner, B.E.; Buchanan, J.A.; Clement, J.M.; Empl, A.; Mutchler, G.S.; Toshkov, S. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.; Eiseman, S.E.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C. [Brookhaven National Lab., Upton, NY (United States); Chan, C.S.; Kramer, M.A.; Lindenbaum, S.J. [City Coll., New York, NY (United States); Hallman, T.J.; Madansky, L. [Johns Hopkins Univ., Baltimore, MD (United States); Peaslee, D.C. [Maryland Univ., College Park, MD (United States)

    1991-12-31

    A Large Angle Multiplicity Detector (LAMD) system has been developed and used at the BNL experiment E854: Antiproton Nucleus Interactions. This system performed well with an energetic antiproton beam. Charged particle multiplicity distributions from pbar annihilations were measured. We discuss the design and performance of the LAMD system in this paper. 6 refs., 10 figs.

  20. A silicon multiplicity detector system for an experiment on the interaction of antiprotons with nuclei at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, S.; Bonner, B.E.; Buchanan, J.A.; Clement, J.M.; Empl, A.; Mutchler, G.S.; Toshkov, S. (Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.); Eiseman, S.E.; Etkin, A.; Foley, K.J. (Brookhaven National Lab., Upton, NY (United States))

    1992-08-01

    A Large Angle Multiplicity Detector (LAMD) system has been developed and used at the BNL experiment E854: Antiproton Nucleus Interactions. This system performed well with an energetic antiproton beam. Charged particle multiplicity distributions from [bar p] annihilations were measured. The authors discuss the design and performance of the LAMD system in this paper.

  1. Active on-line detector for in-room radiotherapy neutron measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, F., E-mail: faustino.gomez@usc.e [Dpt. Fisica de Particulas, Facultad de Fisica, Campus Sur, Univ. Santiago de Compostela, Santiago 15782 (Spain); Sanchez-Doblado, F. [Dpt. de Fisiologia Medica y Biofisica, Univ. Sevilla, Sevilla (Spain); Hospital Virgen Macarena, Sevilla (Spain); Iglesias, A. [Dpt. Fisica de Particulas, Facultad de Fisica, Campus Sur, Univ. Santiago de Compostela, Santiago 15782 (Spain); Domingo, C. [Dpt. Fisica, Univ. Autonoma Barcelona, Barcelona (Spain)

    2010-12-15

    The measurement of the neutron fluence produced inside a radiotherapy installation has been a matter of concern specially in the photon high megavoltage modalities. Until now, due to the pulsed nature of the beam and the high photon fluence inside the radiotherapy room, only passive methods were considered reliable. In this work we describe a neutron detector, based on neutron sensitive SRAM devices, that can operate inside the treatment room and is insensitive to the scattered photon fluence. This device has been used to estimate the neutron production and the patient exposure to neutrons in several clinical installations with different linac commercial models. The detection principle is based on the production of Single Event Upset (SEU) of memory states on modern sub-micron technology SRAMs. Spectral sensitivity was initially studied using low energy neutron shielding (boron and cadmium layers) and later using dedicated calibration neutron beams. With a 3 mm thick flex-boron shield, the SEU rate was reduced to around 5% of the unshielded rate, demonstrating that the dominant contribution of the SEU cross section of the chosen SRAM was due to low energy neutrons. The total memory size was scaled to obtain a response repeatability with relative typical uncertainty of about 2% for 1000 Monitor Units (MU) in a 15 MV accelerator facility with excellent linearity with MU. The sensitivity of this digital detector is around 0.3 {mu}Sv H{sup *}(10) per event and considering the signal to fluence ratio around 2 x 10{sup -4} event cm{sup 2}.

  2. Status Report on the Antiproton Decelerator (AD)

    CERN Document Server

    Erikson, T; Möhl, D

    2001-01-01

    CERN's new Antiproton Decelerator (AD) has been delivering a 100 MeV/c antiproton beam to three experiments (ASACUSA, AHENA and ATRAP) since July 10th, 2000. In this status report, we summarise the initial performance of the AD, draw provisional conclusions from the first month of operation and finally give some prospects for the future.

  3. Antiproton, positron, and electron imaging with a microchannel plate/phosphor detector

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jørgensen, L V; Kerrigan, S J; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Yamazaki, Y

    2009-01-01

    A microchannel plate (MCP)/phosphor screen assembly has been used to destructively measure the radial profile of cold, confined antiprotons, electrons, and positrons in the ALPHA experiment, with the goal of using these trapped particles for antihydrogen creation and confinement. The response of the MCP to low energy (10-200 eV, <1 eV spread) antiproton extractions is compared to that of electrons and positrons.

  4. Annihilation of Antiprotons in Light Nuclei

    Institute of Scientific and Technical Information of China (English)

    M. A. Rana; E. U. Khan; M. I. Shahzad; I. E. Qureshi; F. Malik; G. Sher; S. Manzoor; H. A. Khan

    2006-01-01

    @@ CR-39 detectors have been exposed to a 5.9-MeV antiproton beam using the low energy antiproton ring (LEAR) facility at CERN. At this energy, tracks of antiprotons appear in a CR-39 detector after 135 min of etching in 6 M NaOH at 70℃ . Fluence of the antiproton beam has been determined using track density. We have also found tracks in the etched CR-39 detector at different depths (250-500μm). These tracks have resulted from the annihilation of antiprotons with the constituents (H, C and O) of the CR-39 detector. The goal of the experiment is to develop a simple and low-cost method to study properties of antiparticles and those formed after annihilation of these particles with the target matter.

  5. X-rays from anti-protonic hydrogen and deuterium

    Energy Technology Data Exchange (ETDEWEB)

    Gorringe, T.P.; Davies, J.D.; Lowe, J.; Nelson, J.M.; Playfer, S.M.; Pyle, G.J.; Squier, G.T.A.; Baker, C.A.; Batty, C.J.; Clark, S.A.; Kilvington, A.I.; Moir, J.; Sakamoto, S.; Welsh, R.E.; Winter, R.G.; Lingeman, E.W.A.

    1985-11-07

    Antiprotons from the LEAR facility at CERN were stopped in targets of gaseous H/sub 2/ or D/sub 2/. Yields of L X-rays were measured. K-series from anti p-p atoms were observed. The measured shift and width for the 1s level are ..delta..Esub(1s)=-0.73+-0.15 keV and GAMMAsub(1s)=0.85+-0.39 keV. (orig.).

  6. Particle production in antiproton induced nuclear reactions

    CERN Document Server

    Feng, Zhao-Qing

    2014-01-01

    The quantum molecular dynamics model has been improved to investigate the reaction dynamics induced by antiprotons. The reaction channels of elastic scattering, annihilation, charge exchange and inelastic collisions have been included in the model. Dynamics on particle production, in particular pions, kaons, antikaons and hyperons, is investigated in collisions of $\\overline{p}$ on $^{12}$C, $^{20}$Ne, $^{40}$Ca, $^{112}$Sn, $^{181}$Ta, $^{197}$Au and $^{238}$U from a low to high incident momentum. The rapidity and momentum distributions of $\\pi^{+}$ and protons from the LEAR measurements can be well reproduced. The impacts of system size and incident momentum on particle emissions are investigated from the inclusive spectra, transverse momentum and rapidity distributions. It is found that the annihilations of $\\overline{p}$ on nucleons are of importance on the particle production. Hyperons are mainly produced via meson induced reactions on nucleons and strangeness exchange collisions when the incident moment...

  7. Experimental and computational study of the injection of antiprotons into a positron plasma for antihydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Amole, C.; Capra, A.; Menary, S. [Department of Physics and Astronomy, York University, Toronto, M3J 1P3 Ontario (Canada); Ashkezari, M. D.; Hayden, M. E. [Department of Physics, Simon Fraser University, Burnaby, V5A 1S6 British Columbia (Canada); Baquero-Ruiz, M.; Little, A.; So, C.; Zhmoginov, A. [Department of Physics, University of California, Berkeley, California 94720 (United States); Bertsche, W. [Department of Physics, College of Science, Swansea University, SA2 8PP Swansea (United Kingdom); School of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom); Daresbury Laboratory, Cockcroft Institute, WA4 4AD Warrington (United Kingdom); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Cesar, C. L.; Silveira, D. M. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941 (Brazil); Charlton, M.; Deller, A.; Eriksson, S.; Isaac, C. A.; Madsen, N.; Napoli, S. C.; Shields, C. R. [Department of Physics, College of Science, Swansea University, SA2 8PP Swansea (United Kingdom); Collaboration: ALPHA Collaboration; and others

    2013-04-15

    One of the goals of synthesizing and trapping antihydrogen is to study the validity of charge-parity-time symmetry through precision spectroscopy on the anti-atoms, but the trapping yield achieved in recent experiments must be significantly improved before this can be realized. Antihydrogen atoms are commonly produced by mixing antiprotons and positrons stored in a nested Penning-Malmberg trap, which was achieved in ALPHA by an autoresonant excitation of the antiprotons, injecting them into the positron plasma. In this work, a hybrid numerical model is developed to simulate antiproton and positron dynamics during the mixing process. The simulation is benchmarked against other numerical and analytic models, as well as experimental measurements. The autoresonant injection scheme and an alternative scheme are compared numerically over a range of plasma parameters which can be reached in current and upcoming antihydrogen experiments, and the latter scheme is seen to offer significant improvement in trapping yield as the number of available antiprotons increases.

  8. Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central $d$$+$Au collisions at $\\sqrt{s_{_{NN}}}$=200 GeV

    CERN Document Server

    Adare, A; Ajitanand, N N; Akiba, Y; Akimoto, R; Al-Bataineh, H; Al-Ta'ani, H; Alexander, J; Andrews, K R; Angerami, A; Aoki, K; Apadula, N; Appelt, E; Aramaki, Y; Armendariz, R; Aschenauer, E C; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Bannier, B; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Ben-Benjamin, J; Bennett, R; Bhom, J H; Blau, D S; Bok, J S; Boyle, K; Brooks, M L; Broxmeyer, D; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Campbell, S; Caringi, A; Castera, P; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; del Valle, Z Conesa; Connors, M; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Dayananda, M K; Denisov, A; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; D'Orazio, L; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Gal, C; Garishvili, I; Glenn, A; Gong, H; Gong, X; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Grim, G; Perdekamp, M Grosse; Gunji, T; Guo, L; Gustafsson, H -Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Harper, C; Hashimoto, K; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Hollis, R S; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hori, Y; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Iinuma, H; Ikeda, Y; Imai, K; Inaba, M; Iordanova, A; Isenhower, D; Ishihara, M; Issah, M; Ivanischev, D; Iwanaga, Y; Jacak, B V; Jia, J; Jiang, X; Jin, J; John, D; Johnson, B M; Jones, T; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kamin, J; Kaneti, S; Kang, B H; Kang, J H; Kang, J S; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, D J; Kim, E -J; Kim, Y -J; Kim, Y K; Kinney, E; Kiss, Á; Kistenev, E; Kleinjan, D; Kline, P; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotov, D; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K S; Lee, S H; Lee, S R; Leitch, M J; Leite, M A L; Li, X; Lichtenwalner, P; Liebing, P; Lim, S H; Levy, L A Linden; Liška, T; Liu, H; Liu, M X; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Malik, M D; Manion, A; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Means, N; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Miki, K; Milov, A; Mitchell, J T; Miyachi, Y; Mohanty, A K; Moon, H J; Morino, Y; Morreale, A; Morrison, D P; Motschwiller, S; Moukhanova, T V; Murakami, T; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Newby, J; Nguyen, M; Nihashi, M; Nouicer, R; Nyanin, A S; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, B H; Park, I H; Park, S K; Park, W J; Pate, S F; Patel, L; Pei, H; Peng, J -C; Pereira, H; Peressounko, D Yu; Petti, R; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Qu, H; Rak, J; Ravinovich, I; Read, K F; Rembeczki, S; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sarsour, M; Sato, T; Savastio, M; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Seto, R; Sharma, D; Shein, I; Shibata, T -A; Shigaki, K; Shim, H H; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Sodre, T; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sun, J; Sziklai, J; Takagui, E M; Takahara, A; Taketani, A; Tanabe, R; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tennant, E; Themann, H; Thomas, D; Thomas, T L; Togawa, M; Toia, A; Tomášek, L; Tomášek, M; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Utsunomiya, K; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Virius, M; Vossen, A; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Watanabe, Y S; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Woody, C L; Wright, R M; Wysocki, M; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; Yoo, J S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zelenski, A; Zhou, S

    2014-01-01

    We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central $d$$+$Au and minimum bias $p$$+$$p$ collisions at \\sqsn=200 GeV. The charged hadron is measured at midrapidity $|\\eta|$ 2.75 is observed in $d$$+$Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength $v_2$ for inclusive charged hadrons at midrapidity up to $p_T=$ 4.5 GeV/$c$. We also present the measurement of $v_2$ for identified $\\pi^{\\pm}$ and (anti)protons in central $d$$+$Au collisions, and observe a mass-ordering pattern similar to that seen in heavy ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from $p$$+$Pb at \\sqsn=5.02 TeV. The magnitude of the mass-ordering in $d$$+$Au is found to be smaller than that in $p$$+$Pb collisions, which may indicate smaller radial flow in lower energy $d$$+$Au collisions.

  9. Measurement of Long-Range Angular Correlation and Quadrupole Anisotropy of Pions and (Anti)Protons in Central d+Au Collisions at sqrt[s_{NN}]=200 GeV.

    Science.gov (United States)

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Akimoto, R; Al-Bataineh, H; Al-Ta'ani, H; Alexander, J; Andrews, K R; Angerami, A; Aoki, K; Apadula, N; Appelt, E; Aramaki, Y; Armendariz, R; Aschenauer, E C; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Bannier, B; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Ben-Benjamin, J; Bennett, R; Bhom, J H; Blau, D S; Bok, J S; Boyle, K; Brooks, M L; Broxmeyer, D; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Campbell, S; Caringi, A; Castera, P; Chen, C-H; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Conesa Del Valle, Z; Connors, M; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Dayananda, M K; Denisov, A; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; D'Orazio, L; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Gal, C; Garishvili, I; Glenn, A; Gong, H; Gong, X; Gonin, M; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grim, G; Grosse Perdekamp, M; Gunji, T; Guo, L; Gustafsson, H-Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Harper, C; Hashimoto, K; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Hollis, R S; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hori, Y; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Iinuma, H; Ikeda, Y; Imai, K; Inaba, M; Iordanova, A; Isenhower, D; Ishihara, M; Issah, M; Ivanischev, D; Iwanaga, Y; Jacak, B V; Jia, J; Jiang, X; Jin, J; John, D; Johnson, B M; Jones, T; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kamin, J; Kaneti, S; Kang, B H; Kang, J H; Kang, J S; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, D J; Kim, E-J; Kim, Y-J; Kim, Y K; Kinney, E; Kiss, Á; Kistenev, E; Kleinjan, D; Kline, P; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotov, D; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K S; Lee, S H; Lee, S R; Leitch, M J; Leite, M A L; Li, X; Lichtenwalner, P; Liebing, P; Lim, S H; Linden Levy, L A; Liška, T; Liu, H; Liu, M X; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Malik, M D; Manion, A; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Means, N; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Miki, K; Milov, A; Mitchell, J T; Miyachi, Y; Mohanty, A K; Moon, H J; Morino, Y; Morreale, A; Morrison, D P; Motschwiller, S; Moukhanova, T V; Murakami, T; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Newby, J; Nguyen, M; Nihashi, M; Nouicer, R; Nyanin, A S; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, B H; Park, I H; Park, S K; Park, W J; Pate, S F; Patel, L; Pei, H; Peng, J-C; Pereira, H; Peressounko, D Yu; Petti, R; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Qu, H; Rak, J; Ravinovich, I; Read, K F; Rembeczki, S; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sarsour, M; Sato, T; Savastio, M; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Seto, R; Sharma, D; Shein, I; Shibata, T-A; Shigaki, K; Shim, H H; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Sodre, T; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sun, J; Sziklai, J; Takagui, E M; Takahara, A; Taketani, A; Tanabe, R; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tennant, E; Themann, H; Thomas, D; Thomas, T L; Togawa, M; Toia, A; Tomášek, L; Tomášek, M; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Utsunomiya, K; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Virius, M; Vossen, A; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Watanabe, Y S; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Woody, C L; Wright, R M; Wysocki, M

    2015-05-15

    We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sqrt[s_{NN}]=200 GeV. The charged hadron is measured at midrapidity |η|2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v_{2} for inclusive charged hadrons at midrapidity up to p_{T}=4.5 GeV/c. We also present the measurement of v_{2} for identified π^{±} and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sqrt[s_{NN}]=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

  10. That was LEAP 05! or Antiproton Physics in a Nutshell

    Science.gov (United States)

    Kienle, Paul

    2005-10-01

    A personally flavored review of selected topics of LEAP 05 is given, with focus on some recent interesting developments in low and medium energy antiproton physics, such as fundamental symmetries and antihydrogen, antihadron-hadron systems, antiproton-proton annihilation, nuclear structure studies with antiprotons, and the FAIR facility for antiproton and ion research.

  11. High spatial resolution dosimetric response maps for radiotherapy ionization chambers measured using kilovoltage synchrotron radiation

    Science.gov (United States)

    Butler, D. J.; Stevenson, A. W.; Wright, T. E.; Harty, P. D.; Lehmann, J.; Livingstone, J.; Crosbie, J. C.

    2015-11-01

    Small circular beams of synchrotron radiation (0.1 mm and 0.4 mm in diameter) were used to irradiate ionization chambers of the types commonly used in radiotherapy. By scanning the chamber through the beam and measuring the ionization current, a spatial map of the dosimetric response of the chamber was recorded. The technique is able to distinguish contributions to the large-field ionization current from the chamber walls, central electrode and chamber stem. Scans were recorded for the NE 2571 Farmer chamber, the PTW 30013, IBA FC65-G Farmer-type chambers, the NE 2611A and IBA CC13 thimble chambers, the PTW 31006 and 31014 pinpoint chambers, the PTW Roos and Advanced Markus plane-parallel chambers, and the PTW 23342 thin-window soft x-ray chamber. In all cases, large contributions to the response arise from areas where the incident beam grazes the cavity surfaces. Quantitative as well as qualitative information about the relative chamber response was extracted from the maps, including the relative contribution of the central electrode. Line scans using monochromatic beams show the effect of the photon energy on the chamber response. For Farmer-type chambers, a simple Monte Carlo model was in good agreement with the measured response.

  12. Conformal fields in prostate radiotherapy: A comparison between measurement, calculation and simulation

    Directory of Open Access Journals (Sweden)

    Seied R Mahdavi

    2012-01-01

    Full Text Available Aims: The objective of this study is to evaluate the accuracy of a treatment planning system (TPS for calculating the dose distribution parameters in conformal fields (CF. Dosimetric parameters of CF′s were compared between measurement, Monte Carlo simulation (MCNP4C and TPS calculation. Materials and Methods: Field analyzer water phantom was used for obtaining percentage depth dose (PDD curves and beam profiles (BP of different conformal fields. MCNP4C was used to model conformal fields dose specification factors and head of linear accelerator varian model 2100C/D. Results: Results showed that the distance to agreement (DTA and dose difference (DD of our findings were well within the acceptance criteria of 3 mm and 3%, respectively. Conclusions: According to this study it can be revealed that TPS using equivalent tissue air ratio calculation method is still convenient for dose prediction in non small conformal fields normally used in prostate radiotherapy. It was also showed that, since there is a close correlation with Monte Carlo simulation, measurements and TPS, Monte Carlo can be further confirmed for implementation and calculation dose distribution in non standard and complex conformal irradiation field for treatment planning systems.

  13. A new active method for the measurement of slow-neutron fluence in modern radiotherapy treatment rooms

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, F; Iglesias, A [Departamento de Fisica de Particulas, Universidad de Santiago, 15782-Santiago (Spain); Doblado, F Sanchez [Hospital Universitario Virgen Macarena, Radiofisica and Departamento de Fisiologia Medica y Biofisica, Facultad de Medicina, Universidad de Sevilla (Spain)], E-mail: faustino.gomez@usc.es

    2010-02-21

    This work focuses on neutron monitoring at clinical linac facilities during high-energy modality radiotherapy treatments. Active in-room measurement of neutron fluence is a complex problem due to the pulsed nature of the fluence and the presence of high photon background, and only passive methods have been considered reliable until now. In this paper we present a new active method to perform real-time measurement of neutron production around a medical linac. The device readout is being investigated as an estimate of patient neutron dose exposure on each radiotherapy session. The new instrument was developed based on neutron interaction effects in microelectronic memory devices, in particular using neutron-sensitive SRAM devices. This paper is devoted to the description of the instrument and measurement techniques, presenting the results obtained together with their comparison and discussion. Measurements were performed in several standard clinical linac facilities, showing high reliability, being insensitive to the photon fluence and EM pulse present inside the radiotherapy room, and having detector readout statistical relative uncertainties of about 2% on measurement of neutron fluence produced by 1000 monitor units irradiation runs.

  14. Antiproton--Proton Scattering Experiments with Polarization

    CERN Document Server

    Lenisa, P; Lenisa, Paolo; Rathmann, Frank

    2005-01-01

    The document describes the physics case of the PAX experiment using polarized antiprotons, which has recently been proposed for the new Facility for Antiprotons and Ions Research (FAIR) at GSI--Darmstadt. Polarized antiprotons provide access to a wealth of single-- and double--spin observables, thereby opening a new window to physics uniquely accessible at the HESR. The polarized antiprotons would be most efficiently produced by spin--filtering in a dedicated Antiproton Polarizer Ring (APR) using an internal polarized hydrogen gas target. In the proposed collider scenario of the PAX experiment, polarized protons stored in a COSY--like Cooler Storage Ring (CSR) up to momenta of 3.5 GeV/c are bombarded head--on with 15 GeV/c polarized antiprotons stored in the HESR. This asymmetric double--polarized antiproton--proton collider is ideally suited to map, e.g., the transversity distribution in the proton. The proposed detector consists of a large--angle apparatus optimized for the detection of Drell--Yan electron ...

  15. Saturation of low-energy antiproton annihilation on nuclei

    Science.gov (United States)

    Gal, A.; Friedman, E.; Batty, C. J.

    2000-10-01

    Recent measurements of very low-energy (pL0, parallels the recent prediction, for /E<0, that the level widths of /p¯ atoms saturate and, hence, that /p¯ deeply bound atomic states are relatively narrow. Antiproton annihilation cross sections are calculated at pL=57 MeV//c across the periodic table, and their dependence on /Z and /A is classified and discussed with respect to the Coulomb focussing effect at very low energies.

  16. A detector to search for antiproton decay at the Fermilab antiproton accumulator

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, T. [Pennsylvania State Univ., University Park, PA (United States); Buchanan, C.; Corbin, B.; Lindgren, M.; Muller, T.; Scott, A. [University of California at Los Angeles, Los Angeles, CA 90024 (United States); Geer, S.; Marriner, J.; Martens, M.; Ray, R.; Streets, J.; Wester, W. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Gustafson, R. [University of Michigan, Ann Arbor, MI 48109 (United States); Hu, M.; Snow, G.R. [University of Nebraska-Lincoln, Lincoln, NE (United States); APEX Collaboration

    1998-07-11

    We describe the experimental apparatus used by the APEX experiment (Experiment 868) at the Fermilab antiproton accumulator. The experiment is designed to search for decays of 8.9 GeV/c antiprotons as they traverse a 3.7 m long evacuated decay tank inserted in a straight section of the antiproton accumulator ring. The detector components in the experimental set-up are discussed individually, and the performance of the experiment during data-taking is described. (orig.)

  17. Study of X-Ray and $\\gamma$-Ray Spectra from Antiprotonic Atoms at the Slowly Extracted Antiproton Beam of LEAR

    CERN Multimedia

    2002-01-01

    This experiment will study the X-ray spectra of antiprotonic atoms and the $\\gamma$ spectra of residual nuclei after the antiproton absorption. We intend to begin with measurements on selected isotopically pure targets. Strong interaction effects, the antiproton absorption and the atomic cascade are analysed through the measurement of energies, lineshapes, relative and absolute intensities of all observable lines. The experiments are continued to determine st in resolved fine structure levels and in different isotopes of the same element. Coincidence techniques may be applied. All components of the experimental set-up are already existing from previous experiments and we could begin the measurements with any slowly extracted beam of low energy at LEAR.

  18. Output trends, characteristics, and measurements of three megavoltage radiotherapy linear accelerators.

    Science.gov (United States)

    Hossain, Murshed

    2014-07-08

    The purpose of this study is to characterize and understand the long-term behavior of the output from megavoltage radiotherapy linear accelerators. Output trends of nine beams from three linear accelerators over a period of more than three years are reported and analyzed. Output, taken during daily warm-up, forms the basis of this study. The output is measured using devices having ion chambers. These are not calibrated by accredited dosimetry laboratory, but are baseline-compared against monthly output which is measured using calibrated ion chambers. We consider the output from the daily check devices as it is, and sometimes normalized it by the actual output measured during the monthly calibration of the linacs. The data show noisy quasi-periodic behavior. The output variation, if normalized by monthly measured "real' output, is bounded between ± 3%. Beams of different energies from the same linac are correlated with a correlation coefficient as high as 0.97, for one particular linac, and as low as 0.44 for another. These maximum and minimum correlations drop to 0.78 and 0.25 when daily output is normalized by the monthly measurements. These results suggest that the origin of these correlations is both the linacs and the daily output check devices. Beams from different linacs, independent of their energies, have lower correlation coefficient, with a maximum of about 0.50 and a minimum of almost zero. The maximum correlation drops to almost zero if the output is normalized by the monthly measured output. Some scatter plots of pairs of beam output from the same linac show band-like structures. These structures are blurred when the output is normalized by the monthly calibrated output. Fourier decomposition of the quasi-periodic output is consistent with a 1/f power law. The output variation appears to come from a distorted normal distribution with a mean of slightly greater than unity. The quasi-periodic behavior is manifested in the seasonally averaged output

  19. Supplemental figure: Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at $\\mathbf{\\sqrt{{\\textit s}_{\\rm NN}}}$ = 2.76 TeV

    CERN Document Server

    2015-01-01

    This note provides a supplemental figure for data on ``Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions $\\mathbf{\\sqrt{{\\textit s}_{\\rm NN}}}$ = 2.76~TeV" published in \\href{http://www.sciencedirect.com/science/article/pii/S037026931300004X}{Phys.\\ Lett.\\ B {\\bf 719}, 18 (2013)}, \\href{http://arxiv.org/abs/1205.5761}{arXiv:1205.5761}. The figure~(\\ref{fig:v2_pid}) presents the $v_2$ of charged pions and protons (particles and anti-particles are not distinguished in this analysis) from the event plane method as a function of transverse momentum for different centrality classes as reported in Fig. 5 of the \\href{http://www.sciencedirect.com/science/article/pii/S037026931300004X}{publication}. The proton $v_2$ is higher than that of pions out to $\\pt=8$~GeV/$c$ where the uncertainties become large.

  20. X-rays from antiprotonic3He and4He

    Science.gov (United States)

    Schneider, M.; Bacher, R.; Blüm, P.; Gotta, D.; Heitlinger, K.; Kunold, W.; Rohmann, D.; Egger, J.; Simons, L. M.; Elsener, K.

    1991-06-01

    Antiprotonic X-rays from the helium isotopes have been observed at pressures of 36, 72, 375 and 600 mbar. The antiproton beam from LEAR with momenta of 309 and 202 MeV/c has been stopped at these pressures using the cyclotron trap. The X-rays were detected with Si (Li) and intrinsic Ge semiconductor detectors. Absolute X-ray yields were determined and the strong-interaction 2p shifts and the 2p and 3d broadenings measured to be ɛ2p=(-17±4) eV, Γ2p=(25±9) eV and Γ3d=(2.14 ±0.18) meV for ¯p3He and ɛ2p=(-18±2) eV, Γ2p =(45±5) eV and Γ3d=(2.36±0.10) meV for ¯p4He.

  1. Secondary electron emission in antiproton-carbon foil collisions

    Energy Technology Data Exchange (ETDEWEB)

    Komaki, K.; Yamazaki, Y.; Kuroki, K. (Inst. of Physics, Coll. of Arts and Sciences, Univ. of Tokyo (Japan)); Andersen, L.H.; Horsdal-Pedersen, E.; Hvelplund, P.; Knudsen, H.; Moeller, S.P.; Uggerhoej, E. (Inst. of Physics, Univ. of Aarhus (Denmark)); Elsener, K. (CERN, Geneva (Switzerland))

    1991-04-01

    Energy spectra of electrons emitted in the forward direction by antiproton and proton bombardments on carbon foil targets were measured in the incident energy region from 500 to 750 keV. In the spectra for antiproton impact, no sharp anticusp, which is expected in place of the cusp in the case of the proton impact, is recognized and a small bump is found at 50 eV below the cusp energy. The spectral profile in the equivelocity region, including smearing out of the anticusp, together with the energy and intensity of the bump, is consistent with a theoretical prediction for wake-riding electrons based on the classical trajectory Monte Carlo method. (orig.).

  2. Measurement and properties of dose-area product ratio in external small-beam radiotherapy.

    Science.gov (United States)

    Niemelä, Jarkko Tapio; Partanen, Mari; Ojala, Jarkko; Sipilae, Petri; Björkqvist, Mikko; Kapanen, Mika; Keyriläinen, Jani

    2017-03-22

    In small-beam radiation therapy (RT) the measurement of beam quality parameter i.e. tissue-phantom ratio or TPR20,10 with conventional point detector is a challenge. To obtain reliable results, one has to consider potential sources of error, including volume averaging and adjustment of the point detector into the narrow beam. To overcome these challenges, a different type of possible beam quality parameter in small beams was studied, namely the dose-area product ratio or DAPR20,10. With this method, the measurement of a dose-area product (DAP) with a large-area plane-parallel chamber (LAC) eliminates the uncertainties in detector positioning and volume averaging present with the use of a point detector. In this study, properties of DAPR20,10 of cone-collimated 6 MV photon beam were investigated with Monte Carlo (MC) calculations and the obtained values were compared to measurements obtained by two LAC detectors PTW Type 34073 and PTW Type 34070. In addition, the possibility of determining the DAP with EBT3 film and Razor diode detector was studied. The determination of DAPR20,10 value was found to be feasible in external small-beam radiotherapy of cone-collimated beams with diameters from 4 to 40 mm with the two LACs, MC calculation and Razor diode. Measurements indicated a constant DAPR20,10 value for fields from 20 to 40 mm in diameter with maximum relative change of 0.6%, but an increase of 7.0% for fields from 20 to 4 mm in diameter for PTW Type 34070 chamber. Simulations and measurements showed an increase of DAPR20,10 with increasing LAC size or dose integral area for studied cone-collimated 6 MV photon beams from 4 to 40 mm in diameter. This has a consequence that with reported DAPR20,10 value there should be a reference to the size of the used LAC active area or the DAP integration area.

  3. Antiprotons from dark matter annihilation in the Galaxy. Astrophysical uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Evoli, Carmelo [Chinese Academy of Sciences, Beijing (China). National Astronomical Observatories; Cholis, Ilias; Ullio, Piero [SISSA, Sezione di Trieste (Italy); INFN, Sezione di Trieste (Italy); Grasso, Dario [INFN, Sezione di Pisa (Italy); Maccione, Luca [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2011-08-15

    The latest years have seen steady progresses in WIMP dark matter (DM) searches, with hints of possible signals suggested by both direct and indirect detection experiments. Antiprotons can play a key role validating those interpretations since they are copiously produced by WIMP annihilations in the Galactic halo, and the secondary antiproton background produced by Cosmic Ray (CR) interactions is predicted with fair accuracy and matches the observed spectrum very well. Using the publicly available numerical DRAGON code, we reconsider antiprotons as a tool to constrain DM models discussing its power and limitations. We provide updated constraints on a wide class of annihilating DM models by comparing our predictions against the most up-to-date anti p measurements, taking also into account the latest spectral information on the p, He and other CR nuclei fluxes. Doing that, we probe carefully the uncertainties associated to both secondary and DM originated antiprotons, by using a variety of distinctively different assumptions for the propagation of CRs and for the DM distribution in the Galaxy. We find that the impact of the astrophysical uncertainties on constraining the DM properties can be much stronger, up to a factor of {proportional_to}50, than the one due to uncertainties on the DM distribution ({proportional_to}2-6). Remarkably, even reducing the uncertainties on the propagation parameters derived by local observables, non-local effects can still change DM model constraints even by 50%. Nevertheless, current anti p data place tight constraints on DM models, excluding some of those suggested in connection with indirect and direct searches. Finally we discuss the power of upcoming CR spectral data from the AMS-02 observatory to drastically reduce the uncertainties discussed in this paper and estimate the expected sensitivity of this instrument to some sets of DM models. (orig.)

  4. Antiproton annihilation physics in the Monte Carlo particle transport code SHIELD-HIT12A

    Energy Technology Data Exchange (ETDEWEB)

    Taasti, Vicki Trier; Knudsen, Helge [Dept. of Physics and Astronomy, Aarhus University (Denmark); Holzscheiter, Michael H. [Dept. of Physics and Astronomy, Aarhus University (Denmark); Dept. of Physics and Astronomy, University of New Mexico (United States); Sobolevsky, Nikolai [Institute for Nuclear Research of the Russian Academy of Sciences (INR), Moscow (Russian Federation); Moscow Institute of Physics and Technology (MIPT), Dolgoprudny (Russian Federation); Thomsen, Bjarne [Dept. of Physics and Astronomy, Aarhus University (Denmark); Bassler, Niels, E-mail: bassler@phys.au.dk [Dept. of Physics and Astronomy, Aarhus University (Denmark)

    2015-03-15

    The Monte Carlo particle transport code SHIELD-HIT12A is designed to simulate therapeutic beams for cancer radiotherapy with fast ions. SHIELD-HIT12A allows creation of antiproton beam kernels for the treatment planning system TRiP98, but first it must be benchmarked against experimental data. An experimental depth dose curve obtained by the AD-4/ACE collaboration was compared with an earlier version of SHIELD-HIT, but since then inelastic annihilation cross sections for antiprotons have been updated and a more detailed geometric model of the AD-4/ACE experiment was applied. Furthermore, the Fermi–Teller Z-law, which is implemented by default in SHIELD-HIT12A has been shown not to be a good approximation for the capture probability of negative projectiles by nuclei. We investigate other theories which have been developed, and give a better agreement with experimental findings. The consequence of these updates is tested by comparing simulated data with the antiproton depth dose curve in water. It is found that the implementation of these new capture probabilities results in an overestimation of the depth dose curve in the Bragg peak. This can be mitigated by scaling the antiproton collision cross sections, which restores the agreement, but some small deviations still remain. Best agreement is achieved by using the most recent antiproton collision cross sections and the Fermi–Teller Z-law, even if experimental data conclude that the Z-law is inadequately describing annihilation on compounds. We conclude that more experimental cross section data are needed in the lower energy range in order to resolve this contradiction, ideally combined with more rigorous models for annihilation on compounds.

  5. Interpretation of the cosmic ray positron and antiproton fluxes

    CERN Document Server

    Lipari, Paolo

    2016-01-01

    The spectral shape of cosmic ray positrons and antiprotons has been accurately measured in the broad kinetic energy range 1-350 GeV. In the higher part of this range (E > 30 GeV) the e+ and pbar are both well described by power laws with spectral indices gamma[e+] = 2.77 +-0.02 and gamma[pbar] = 2.78 +- 0.04 that are approximately equal to each other and to the spectral index of protons. In the same energy range the positron/antiproton flux ratio has the approximately constant value 2.04+-0.04, that is consistent with being equal to the ratio e_/pbar calculated for the conventional mechanism of production, where the antiparticles are created as secondaries in the inelastic interactions of primary cosmic rays with interstellar gas. The positron/antiproton ratio at lower energy is significantly higher (reaching the approximate value e+/pbar = 100 for E around 1 GeV), but in the entire energy range 1-350 GeV, the flux ratio is consistent with being equal to ratio of the production rates in the conventional mecha...

  6. On Antiproton Production in 158 GeV/c Proton-Carbon Collisions and Nuclear Temperature of Interacting System

    Directory of Open Access Journals (Sweden)

    Fu-Hu Liu

    2013-01-01

    Full Text Available The multisource thermal model is used in this paper to analyze the antiproton (p¯ production process in high-energy proton-carbon (p-C collisions. The transverse momentum, Feynman variable, and rapidity distributions of antiprotons in the nucleon-nucleon center-of-mass system are calculated by using the model. The modeling results are compared and found to be in agreement with the experimental data measured by the NA49 Collaboration at 158 GeV/c beam momentum. As a parameter, the nuclear temperature of interacting system extracted from the antiproton spectrum is estimated to be about 150 MeV.

  7. Experimental determination of the complete spin structure for anti-proton + proton -> anti-\\Lambda + \\Lambda at anti-proton beam momentum of 1.637 GeV/c

    CERN Document Server

    Paschke, K D; Berdoz, A; Franklin, G B; Khaustov, P; Meyer, C A; Bradtke, C; Gehring, R; Görtz, S; Harmsen, J; Meier, A; Meyer, W; Radtke, E; Reicherz, G; Dutz, H; Plückthun, M; Schoch, B; Dennert, H; Eyrich, W; Hauffe, J; Metzger, A; Moosburger, M; Stinzing, F; Wirth, S; Fischer, H; Franz, J; Heinsius, F H; Kriegler, E; Schmitt, H; Bunker, B; Hertzog, D; Jones, T; Tayloe, R; Bröders, R; Geyer, R; Kilian, K; Oelert, W; Röhrich, K; Sachs, K; Sefzick, T; Bassalleck, B; Eilerts, S; Fields, D E; Kingsberry, P; Lowe, J; Stotzer, R; Johansson, T; Pomp, S; Wirth, St.

    2006-01-01

    The reaction anti-proton + proton -> anti-\\Lambda + \\Lambda -> anti-proton + \\pi^+ + proton + \\pi^- has been measured with high statistics at anti-proton beam momentum of 1.637 GeV/c. The use of a transversely-polarized frozen-spin target combined with the self-analyzing property of \\Lambda/anti-\\Lambda decay allows access to unprecedented information on the spin structure of the interaction. The most general spin-scattering matrix can be written in terms of eleven real parameters for each bin of scattering angle, each of these parameters is determined with reasonable precision. From these results all conceivable spin-correlations are determined with inherent self-consistency. Good agreement is found with the few previously existing measurements of spin observables in anti-proton + proton -> anti-\\Lambda + \\Lambda near this energy. Existing theoretical models do not give good predictions for those spin-observables that had not been previously measured.

  8. Antiproton production and antideuteron production limits in relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Dover, C.B. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Huang, H.Z.; Van Buren, G. [University of California at Los Angeles, Los Angeles, California 90095 (United States); Barish, K.N. [University of California at Riverside, Riverside, California 92521 (United States); Fadem, B.; Hill, J.C.; Hoversten, R.; Lajoie, J.G.; Libby, B.; Wohn, F.K. [Iowa State University, Ames, Iowa 50011 (United States); Rabin, M.S. [University of Massachusetts, Amherst, Massachusetts 01003 (United States); Haridas, P.; Pless, I.A. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Armstrong, T.A.; Smith, G.A.; Toothacker, W.S. [Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Davies, R.; Hirsch, A.S.; Porile, N.T.; Rimai, A.; Scharenberg, R.P.; Tincknell, M.L. [Purdue University, West Lafayette, Indiana 47907 (United States); Lainis, T. [United States Military Academy, West Point, New York 10996 (United States); Greene, S.V.; Miller, T.E.; Reid, J.D.; Rose, A. [Vanderbilt University, Nashville, Tennessee 37235 (United States); Bennett, S.J.; Cormier, T.M.; Fachini, P.; Li, Q.; Munhoz, M.G.; Pruneau, C.A. [Wayne State University, Detroit, Michigan 48201 (United States); Batsoulli, S.; Chikanian, A.; Coe, S.D.; Finch, L.E.; George, N.K.; Kumar, B.S.; Majka, R.D.; Nagle, J.L.; Pope, J.K.; Rotondo, F.S.; Sandweiss, J.; Slaughter, A.J.; Xu, Z. [Yale University, New Haven, Connecticut 06520 (United States)

    1999-05-01

    We present results from Experiment 864 for antiproton production and antideuteron limits in Au + Pb collisions at 11.5 GeV/c per nucleon. We have measured invariant multiplicities for antiprotons for rapidities 1.4{lt}y{lt}2.4 at low transverse momentum as a function of collision geometry. When compared with the results from Experiment 878 our measurements suggest a significant contribution to the measured antiproton yield from the decay of strange antibaryons. We have also searched for antideuterons and see no statistically significant signal. Thus, we set upper limits on the production at approximately 3{times}10{sup {minus}7} per 10{percent} highest multiplicity Au+Pb interaction. {copyright} {ital 1999} {ital The American Physical Society}

  9. Review and analysis of different types of radiation detectors for measurements in radiotherapy; Revision y analisis de diferentes tipos de detectores para medidas en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Alonso Iracheta, L.; Gomez Martin, C.; Maravilla Limorte, M.; Bejar Navarro, M. J.; Capuz Suarez, B.; Colmenares Fernandez, R.; Moris Pablos, R.; Rot Sanjuan, M. J.

    2011-07-01

    Physical dosimetry is the set of procedures and techniques aimed at establishing the extent and dosimetric variables with characterized radiotherapy sources and equipment and is a topic of great interest in all areas of radiotherapy, including areas where performed dosimetry of small fields such as stereotactic radiotherapy (SRS), intensity Modulated Radiation Therapy (IMRT) and intraoperative radiotherapy (RIO). By reviewing the physics of large fields and small bundles of photons and high energy electrons, we observe that it is difficult to select a single detector that is optimal for all measures of interest: area factors (output factors), depth dose curves (PDD's) and beam profiles with minimal errors, This paper summarizes a literature review to assess which of the different types of detectors available today is suitable for characterizing a beam of radiation.

  10. Role of perfusion SPECT in prediction and measurement of pulmonary complications after radiotherapy for lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Farr, Katherina P.; Khalil, Azza A.; Grau, Cai [Aarhus University Hospital, Department of Oncology, Aarhus C (Denmark); Kramer, Stine; Morsing, Anni [Aarhus University Hospital, Department of Nuclear Medicine and PET Centre, Aarhus C (Denmark)

    2015-07-15

    The purpose of the study was to evaluate the ability of baseline perfusion defect score (DS) on SPECT to predict the development of severe symptomatic radiation pneumonitis (RP) and to evaluate changes in perfusion on SPECT as a method of lung perfusion function assessment after curative radiotherapy (RT) for non-small-cell lung cancer (NSCLC). Patients with NSCLC undergoing curative RT were included prospectively. Perfusion SPECT/CT and global pulmonary function tests (PFT) were performed before RT and four times during follow-up. Functional activity on SPECT was measured using a semiquantitative perfusion DS. Pulmonary morbidity was graded by the National Cancer Institute's Common Terminology Criteria for Adverse Events version 4 for pneumonitis. Patients were divided into two groups according to the severity of RP. A total of 71 consecutive patients were included in the study. Baseline DS was associated with chronic obstructive pulmonary disease. A significant inverse correlation was found between baseline DS and forced expiratory volume in 1 s and diffusing capacity of the lung for carbon monoxide. Patients with severe RP had significantly higher baseline total lung DS (mean 5.43) than those with no or mild symptoms (mean DS 3.96, p < 0.01). PFT results were not different between these two groups. The odds ratio for total lung DS was 7.8 (95 % CI 1.9 - 31) demonstrating the ability of this parameter to predict severe RP. Adjustment for other potential confounders known to be associated with increased risk of RP was performed and did not change the odds ratio. The median follow-up time after RT was 8.4 months. The largest DS increase of 13.3 % was associated with severe RP at 3 months of follow-up (p < 0.01). The development of severe RP during follow-up was not associated with changes in PFT results. Perfusion SPECT is a valuable method for predicting severe RP and for assessing changes in regional functional perfusion after curative RT comparable with

  11. Antiprotons four times more effective than protons for cell irradiation

    CERN Multimedia

    2006-01-01

    "A pioneering experiment at CERN with potential future application in cancer therapy has produced its first results. Started in 2003, ACE (Antiproton Cell Experiment) is the first investigation of the biological effects of antiprotons." (1,5 page)

  12. Antiprotons four times more effective than protons for cell irradiation

    CERN Multimedia

    2007-01-01

    "A pioneering experiment at CERN with potential future application in cancer therapy has produced its first results. Started in 2003, ACE (Antiproton Cell Experiment) is the first investigation of the biological effects of antiprotons." (1,5 page)

  13. Constraining the Higgs portal with antiprotons

    CERN Document Server

    Urbano, Alfredo

    2014-01-01

    The scalar Higgs portal is a compelling model of dark matter (DM) in which a renormalizable coupling with the Higgs boson provides the connection between the visible world and the dark sector. In this paper we investigate the constraint placed on the parameter space of this model by the antiproton data. Due to the fact that the antiproton-to-proton ratio has relative less systematic uncertainties than the antiproton absolute flux, we propose and explore the possibility to combine all the available $\\bar{p}/p$ data. Following this approach, we are able to obtain stronger limits if compared with the existing literature. In particular, we show that most of the parameter space close to the Higgs resonance is ruled out by our analysis. Furthermore, by studying the reach of the future AMS-02 antiproton and antideuteron data, we argue that a DM mass of $\\mathcal{O}(150)$ GeV offers a promising discovery potential. The method of combining all the antiproton-to-proton ratio data proposed in this paper is quite general...

  14. AMS results on positrons and antiprotons in cosmic rays

    Science.gov (United States)

    Kounine, Andrei; AMS Collaboration

    2017-01-01

    AMS-02 is a particle physics detector collecting data on the International Space Station since May 2011. Precision measurements of charged cosmic ray particles have been performed by AMS using a data sample of 85 billion cosmic ray events collected during the first five years of operations on the Station. The latest AMS results on the fluxes and flux ratios of the cosmic ray particles are presented with the emphasis on the measurements of positrons and antiprotons. They show unique features that require accurate theoretical interpretation as to their origin, be it from dark matter collisions or new astrophysical sources. On behalf of AMS.

  15. SU-E-J-88: The Study of Setup Error Measured by CBCT in Postoperative Radiotherapy for Cervical Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Runxiao, L; Aikun, W; Xiaomei, F; Jing, W [The Forth Hospital of Hebei Medical University, Shijiangzhuang, Hebei (China)

    2015-06-15

    Purpose: To compare two registration methods in the CBCT guided radiotherapy for cervical carcinoma, analyze the setup errors and registration methods, determine the margin required for clinical target volume(CTV) extending to planning target volume(PTV). Methods: Twenty patients with cervical carcinoma were enrolled. All patients were underwent CT simulation in the supine position. Transfering the CT images to the treatment planning system and defining the CTV, PTV and the organs at risk (OAR), then transmit them to the XVI workshop. CBCT scans were performed before radiotherapy and registered to planning CT images according to bone and gray value registration methods. Compared two methods and obtain left-right(X), superior-inferior(Y), anterior-posterior (Z) setup errors, the margin required for CTV to PTV were calculated. Results: Setup errors were unavoidable in postoperative cervical carcinoma irradiation. The setup errors measured by method of bone (systemic ± random) on X(1eft.right),Y(superior.inferior),Z(anterior.posterior) directions were(0.24±3.62),(0.77±5.05) and (0.13±3.89)mm, respectively, the setup errors measured by method of grey (systemic ± random) on X(1eft-right), Y(superior-inferior), Z(anterior-posterior) directions were(0.31±3.93), (0.85±5.16) and (0.21±4.12)mm, respectively.The spatial distributions of setup error was maximum in Y direction. The margins were 4 mm in X axis, 6 mm in Y axis, 4 mm in Z axis respectively.These two registration methods were similar and highly recommended. Conclusion: Both bone and grey registration methods could offer an accurate setup error. The influence of setup errors of a PTV margin would be suggested by 4mm, 4mm and 6mm on X, Y and Z directions for postoperative radiotherapy for cervical carcinoma.

  16. Antiproton beam polarizer using a dense polarized target

    Energy Technology Data Exchange (ETDEWEB)

    Wojtsekhowski, Bogdan

    2011-05-01

    We describe considerations regarding the spin filtering method for the antiproton beam. The proposed investigation of the double polarization cross section for antiproton to nucleon interaction is outlined. It will use a single path of the antiproton beam through a dense polarized target, e.g. 3He or CH2, followed by a polarimeter.

  17. Single ionization of helium by 40--3000-keV antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moller, S.P.; Pedersen, J.O.P.; Tang-Petersen, S.; Uggerhoj, E. (Institute of Physics, University of Aarhus, DK-8000 Aarhus C (Denmark)); Elsener, K. (CERN, CH-1211 Geneva (Switzerland)); Morenzoni, E. (PSI, CH-5234 Villigen (Switzerland))

    1990-06-01

    Measurements of single-ionization cross sections for antiproton impact on helium atoms are reported for impact energies ranging from 40 keV to 3 MeV. It is found that the measured cross sections are in good agreement with recent theoretical estimates based on the continuum-distorted-wave approximation. From a comparison with similar proton data, the ratio between antiproton and proton results is obtained. The energy dependence of this ratio is compared with various theoretical estimates and explained as a result of polarization and binding effects.

  18. Single ionization of helium by 40-3000-keV antiprotons

    Science.gov (United States)

    Andersen, L. H.; Hvelplund, P.; Knudsen, H.; Møller, S. P.; Pedersen, J. O. P.; Tang-Petersen, S.; Uggerhøj, E.; Elsener, K.; Morenzoni, E.

    1990-06-01

    Measurements of single-ionization cross sections for antiproton impact on helium atoms are reported for impact energies ranging from 40 keV to 3 MeV. It is found that the measured cross sections are in good agreement with recent theoretical estimates based on the continuum-distorted-wave approximation. From a comparison with similar proton data, the ratio between antiproton and proton results is obtained. The energy dependence of this ratio is compared with various theoretical estimates and explained as a result of polarization and binding effects.

  19. Determination of the antiproton-to-electron mass ratio by precision laser spectroscopy of $\\overline{p}He^{+}$

    CERN Document Server

    Hori, M; Eades, John; Gomikawa, K; Hayano, R S; Ono, N; Pirkl, Werner; Widmann, E; Torii, H A; Juhász, B; Barna, D; Horváth, D

    2006-01-01

    A femtosecond optical frequency comb and continuous-wave pulse- amplified laser were used to measure 12 transition frequencies of antiprotonic helium to fractional precisions of (9-16) 10/sup -9lifetimes hitherto unaccessible to our precision laser spectroscopy method. Comparisons with three-body QED calculations yielded an antiproton-to-electron mass ratio of M/sub pmacron//m/sub e/=1836.152 674(5).

  20. A measurement of forward-backward charge asymmetry of electron-positron pairs in proton-antiproton collision at 1.8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Veramendi, Gregory Francisco

    2003-12-01

    The authors present a measurement of the mass dependence of the forward-backward charge asymmetry for e{sup +}e{sup -} pairs resulting from {gamma}*/Z decays with mass M{sub ee} > 40 GeV/c{sup 2}. The Run II data sample consists of 72 pb{sup -1} of data, which was collected by the CDF detector in {bar p}p collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The measurement is compared with predictions from the Standard Model.

  1. Direct measurement of the W boson decay width in proton-antiproton collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun-jie [Univ. of Maryland, College Park, MD (United States)

    2004-01-01

    This dissertation describes a direct measurement of the W boson total decay width, ΓW, using the D0 detector at the Fermilab Tevatron Collider. The measurement uses an integrated luminosity of 177.3 pb-1 data, collected during the 2002-2003 run. The width is determined from the shape of the transverse mass distribution, MT, by fitting the data in the tail region 100 < MT < 200 GeV. The result if ΓW = 2.011 ± 0.093(stat) ± 0.107(syst) GeV.

  2. Measurement of the W + γ Production in Proton - Anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, Michael H. [Duke Univ., Durham, NC (United States)

    2004-01-01

    The authors present a measurement of the $\\bar{p}$p → Wγ + X → evγ + X production cross section using data form the Collider Detector at Fermilab. The p$\\bar{p}$ collisions were provided by the Tevatron Collider at a center of mass energy of 1.96 TeV. Electroweak theory includes the trilinear vector boson coupling, WWγ, which contributes to the evγ final state. The electron decay channel of the W provides a clean sample to study the production of diboson pairs. The measurement of the production cross section tests the structure of the non-Abelian character of Electroweak theory.

  3. Direct measurement of the W boson decay width in proton-antiproton collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun-jie

    2004-10-01

    This dissertation describes a direct measurement of the W boson total decay width, {Lambda}{sub W}, using the D0 detector at the Fermilab Tevatron Collider. The measurement uses an integrated luminosity of 177.3 pb{sup -1} data, collected during the 2002-2003 run. The width is determined from the shape of the transverse mass distribution, M{sub T}, by fitting the data in the tail region 100 < M{sub T} < 200 GeV. The result if {Lambda}{sub W} = 2.011 {+-} 0.093(stat) {+-} 0.107(syst) GeV.

  4. Evidence for the Stochastic Acceleration of Secondary Antiprotons by Supernova Remnants

    Energy Technology Data Exchange (ETDEWEB)

    Cholis, Ilias [Johns Hopkins U.; Hooper, Dan [Chicago U., KICP; Linden, Tim [Ohio State U.

    2017-01-16

    The antiproton-to-proton ratio in the cosmic-ray spectrum is a sensitive probe of new physics. Using recent measurements of the cosmic-ray antiproton and proton fluxes in the energy range of 1-1000 GeV, we study the contribution to the $\\bar{p}/p$ ratio from secondary antiprotons that are produced and subsequently accelerated within individual supernova remnants. We consider several well-motivated models for cosmic-ray propagation in the interstellar medium and marginalize our results over the uncertainties related to the antiproton production cross section and the time-, charge-, and energy-dependent effects of solar modulation. We find that the increase in the $\\bar{p}/p$ ratio observed at rigidities above $\\sim$ 100 GV cannot be accounted for within the context of conventional cosmic-ray propagation models, but is consistent with scenarios in which cosmic-ray antiprotons are produced and subsequently accelerated by shocks within a given supernova remnant. In light of this, the acceleration of secondary cosmic rays in supernova remnants is predicted to substantially contribute to the cosmic-ray positron spectrum, accounting for a significant fraction of the observed positron excess.

  5. New calculation of antiproton production by cosmic ray protons and nuclei

    CERN Document Server

    Kachelriess, Michael; Ostapchenko, Sergey S

    2015-01-01

    A dramatic increase in the accuracy and statistics of space-borne cosmic ray (CR) measurements has yielded several breakthroughs over the last several years. The most puzzling is the rise in the positron fraction above ~10 GeV over the predictions of the propagation models assuming pure secondary production. The accuracy of the antiproton production cross section is critical for astrophysical applications and searches for new physics since antiprotons in CRs seem to hold the keys to many puzzles including the origin of those excess positrons. However, model calculations of antiproton production in CR interactions with interstellar gas are often employing parameterizations that are out of date or are using outdated physical concepts. That may lead to an incorrect interpretation of antiproton data which could have broad consequences for other areas of astrophysics. In this work, we calculate antiproton production in pp-, pA-, and AA-interactions using EPOS-LHC and QGSJET-II-04, two of the most advanced Monte Ca...

  6. Direct detection of antiprotons with the Timepix3 in a new electrostatic selection beamline

    Science.gov (United States)

    Pacifico, N.; Aghion, S.; Alozy, J.; Amsler, C.; Ariga, A.; Ariga, T.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R. S.; Cabaret, L.; Caccia, M.; Campbell, M.; Caravita, R.; Castelli, F.; Cerchiari, G.; Chlouba, K.; Cialdi, S.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Evans, C.; Ferragut, R.; Fesel, J.; Fontana, A.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Guatieri, F.; Haider, S.; Holmestad, H.; Huse, T.; Jordan, E.; Kellerbauer, A.; Kimura, M.; Krasnický, D.; Lagomarsino, V.; Lansonneur, P.; Lawler, G.; Lebrun, P.; Llopart, X.; Malbrunot, C.; Mariazzi, S.; Marx, L.; Matveev, V.; Mazzotta, Z.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Pagano, D.; Penasa, L.; Petracek, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Ravelli, L.; Resch, L.; Røhne, O. M.; Rotondi, A.; Sacerdoti, M.; Sandaker, H.; Santoro, R.; Scampoli, P.; Smestad, L.; Sorrentino, F.; Spacek, M.; Storey, J.; Strojek, I. M.; Testera, G.; Tietje, I.; Tlustos, L.; Widmann, E.; Yzombard, P.; Zavatarelli, S.; Zmeskal, J.; Zurlo, N.

    2016-09-01

    We present here the first results obtained employing the Timepix3 for the detection and tagging of annihilations of low energy antiprotons. The Timepix3 is a recently developed hybrid pixel detector with advanced Time-of-Arrival and Time-over-Threshold capabilities and has the potential of allowing precise kinetic energy measurements of low energy charged particles from their time of flight. The tagging of the characteristic antiproton annihilation signature, already studied by our group, is enabled by the high spatial and energy resolution of this detector. In this study we have used a new, dedicated, energy selection beamline (GRACE). The line is symbiotic to the AEgIS experiment at the CERN Antiproton Decelerator and is dedicated to detector tests and possibly antiproton physics experiments. We show how the high resolution of the Timepix3 on the Time-of-Arrival and Time-over-Threshold information allows for a precise 3D reconstruction of the annihilation prongs. The presented results point at the potential use of the Timepix3 in antimatter-research experiments where a precise and unambiguous tagging of antiproton annihilations is required.

  7. Direct detection of antiprotons with the Timepix3 in a new electrostatic selection beamline

    Energy Technology Data Exchange (ETDEWEB)

    Pacifico, N., E-mail: nicola.pacifico@cern.ch [Institute of Physics and Technology, University of Bergen, Allgaten 55, 5007 Bergen (Norway); Aghion, S. [Politecnico of Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); INFN Milano, via Celoria 16, 20133 Milano (Italy); Alozy, J. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Amsler, C.; Ariga, A.; Ariga, T. [Laboratory for High Energy Physics, Albert Einstein Center for Fundamental Physics, University of Bern, 3012 Bern (Switzerland); Bonomi, G. [Department of Mechanical and Industrial Engineering, University of Brescia, via Branze 38, 25123 Brescia (Italy); INFN Pavia, via Bassi 6, 27100 Pavia (Italy); Bräunig, P. [Kirchhoff-Institute for Physics, Heidelberg University, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany); Bremer, J. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Brusa, R.S. [Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Trento (Italy); TIFPA/INFN Trento, via Sommarive 14, 38123 Povo, Trento (Italy); Cabaret, L. [Laboratory Aimé Cotton, University of Paris-Sud, ENS Cachan, CNRS, University Paris-Saclay, 91405 Orsay Cedex (France); Caccia, M. [INFN Milano, via Celoria 16, 20133 Milano (Italy); Department of Science, University of Insubria, Via Valleggio 11, 22100 Como (Italy); Campbell, M. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Caravita, R. [Department of Physics, University of Genova, via Dodecaneso 33, 16146 Genova (Italy); INFN Genova, via Dodecaneso 33, 16146 Genova (Italy); Castelli, F. [INFN Milano, via Celoria 16, 20133 Milano (Italy); Department of Physics, University of Milano, via Celoria 16, 20133 Milano (Italy); Cerchiari, G. [Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, 69117 Heidelberg (Germany); Chlouba, K. [Czech Technical University, Prague, Brehov 7, 11519 Prague 1 (Czech Republic); and others

    2016-09-21

    We present here the first results obtained employing the Timepix3 for the detection and tagging of annihilations of low energy antiprotons. The Timepix3 is a recently developed hybrid pixel detector with advanced Time-of-Arrival and Time-over-Threshold capabilities and has the potential of allowing precise kinetic energy measurements of low energy charged particles from their time of flight. The tagging of the characteristic antiproton annihilation signature, already studied by our group, is enabled by the high spatial and energy resolution of this detector. In this study we have used a new, dedicated, energy selection beamline (GRACE). The line is symbiotic to the AEgIS experiment at the CERN Antiproton Decelerator and is dedicated to detector tests and possibly antiproton physics experiments. We show how the high resolution of the Timepix3 on the Time-of-Arrival and Time-over-Threshold information allows for a precise 3D reconstruction of the annihilation prongs. The presented results point at the potential use of the Timepix3 in antimatter-research experiments where a precise and unambiguous tagging of antiproton annihilations is required.

  8. Measurement of the $W$ Boson Mass in Proton-Antiproton Collisions at a Center of Mass Energy of 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Yacoob, Sahal [Northwestern Univ., Evanston, IL (United States)

    2010-06-01

    I present the measurement of the mass of the W Boson in the electron channel using 4.4 fb-1 of p $\\bar{p}$ collisions at √s = 1:96 TeV recorded by the D0 detector operating at the Fermilab Tevatron Collider.

  9. Measurement of the W + gamma Production in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, Michael H

    2004-10-01

    The authors present a measurement of the {bar p}p {yields} W{gamma} + X {yields} e{nu}{gamma} + X production cross section using data form the Collider Detector at Fermilab. The p{bar p} collisions were provided by the Tevatron Collider at a center of mass energy of 1.96 TeV. Electroweak theory includes the trilinear vector boson coupling, WW{gamma}, which contributes to the e{nu}{gamma} final state. The electron decay channel of the W provides a clean sample to study the production of diboson pairs. The measurement of the production cross section tests the structure of the non-Abelian character of Electroweak theory.

  10. Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton plus Jets Events in 1.96 Tev Proton-Antiproton Collisions

    Energy Technology Data Exchange (ETDEWEB)

    Yorita, Kohei [Waseda Univ., Shinjuku (Japan)

    2005-03-01

    We have measured the top quark mass with the dynamical likelihood method (DLM) using the CDF II detector at the Fermilab Tevatron. The Tevatron produces top and anti-top pairs in pp collisions at a center of mass energy of 1.96 TeV. The data sample used in this paper was accumulated from March 2002 through August 2003 which corresponds to an integrated luminosity of 162 pb-1.

  11. Measurements of bottom anti-bottom azimuthal production correlations in proton - anti-proton collisions at s**(1/2) = 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Taiwan, Inst. Phys. /Argonne /INFN,

    2004-12-01

    The authors have measured the azimuthal angular correlation of b{bar b} production, using 86.5 pb{sup -1} of data collected by Collider Detector at Fermilab (CDF) in p{bar p} collisions at {radical}s = 1.8 TeV during 1994-1995. In high-energy p{bar p} collisions, such as at the Tevatron, b{bar b} production can be schematically categorized into three mechanisms. The leading-order (LO) process is ''flavor creation'', where both b and {bar b} quarks substantially participate in the hard scattering and result in a distinct back-to-back signal in final state. The ''flavor excitation'' and the ''gluon splitting'' processes, which appear at next-leading-order (NLO), are known to make a comparable contribution to total b{bar b} cross section, while providing very different opening angle distributions from the LO process. An azimuthal opening angle between bottom and anti-bottom, {Delta}{phi}, has been used for the correlation measurement to probe the interaction creating b{bar b} pairs. The {Delta}{phi} distribution has been obtained from two different methods. one method measures the {Delta}{phi} between bottom hadrons using events with two reconstructed secondary vertex tags. The other method uses b{bar b} {yields} (J/{psi}X)({ell}X') events, where the charged lepton ({ell}) is an electron (e) or a muon ({mu}), to measure {Delta}{phi} between bottom quarks. The b{bar b} purity is determined as a function of {Delta}{phi} by fitting the decay length of the J/{psi} and the impact parameter of the {ell}. Both methods quantify the contribution from higher-order production mechanisms by the fraction of the b{bar b} pairs produced in the same azimuthal hemisphere, f{sub toward}. The measured f{sub toward} values are consistent with both parton shower Monte Carlo and NLO QCD predictions.

  12. K-shell ionization by antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Mehler, G.; Mueller, B.; Greiner, W.; Soff, G.

    1987-08-01

    We present calculations for the impact-parameter dependence of K-shell ionization rates in p-bar-Cu and in p-bar-Ag collisions at various projectile energies. We show that the effect of the attractive Coulomb potential on the Rutherford trajectory and the antibinding effect caused by the negative charge of the antiproton result in a considerable increase of the ionization probability. Total ionization cross sections for proton and antiproton projectiles are compared with each other and with experimental ionization cross sections for protons.

  13. Measurement of charged particle multiplicities in gluon and quark jets in proton anti-proton collisions at s**(1/2) = 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Taiwan, Inst. Phys. /Argonne /INFN,

    2004-07-01

    The authors report the first model independent measurement of charged particle multiplicities in quark and gluon jets, N{sub q} and N{sub g}, produced at the Tevatron in p{bar p} collisions with center-of-mass energy 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies 41 and 53 GeV by counting charged particle tracks in cones with opening angle of {theta}{sub c} = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = E{sub jet}{theta}{sub c} varies in the range from 12 GeV to 25 GeV. At Q = 19 GeV, the ratio of multiplicities r = N{sub g}/N{sub q} is found to be 1.64 {+-} 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with re-summed perturbative QCD calculations.

  14. Study of Anti-Hydrogen and Plasma Physics 4.Observation of Antiproton Beams and Nonneutral Plasmas

    CERN Document Server

    Hori, Masaki; Fujiwara, Makoto; Kuroda, Naofumi

    2004-01-01

    Diagnostics of antiproton beams and nonneutral plasmas are described in this chapter. Parallel plate secondary electron emission detectors are used to non-destructively observe the beam position and intensity without loss. Plastic scintillation tracking detectors are useful in determining the position of annihilations of antiprotons in the trap. Three-dimensional imaging of antiprotons in a Penning trap is discussed. The unique capability of antimatter particle imaging has allowed the observation of the spatial distribution of particle loss in a trap. Radial loss is localized to small spots, strongly breaking the azimuthal symmetry expected for an ideal trap. By observing electrostatic eigen-modes of nonneutral plasmas trapped in the Multi-ring electrode trap, the non-destructive measurement of plasma parameters is performed.

  15. Parallel plate chambers for monitoring the profiles of high-intensity pulsed antiproton beams

    CERN Document Server

    Hori, Masaki

    2004-01-01

    Two types of beam profile monitor with thin parallel-plate electrodes have been used in experiments carried out at the Low Energy Antiproton Ring (LEAR) and Antiproton Decelerator (AD) of CERN. The detectors were used to measure non-destructively the spatial profiles, absolute intensities, and time structures of 100-300-ns- long beam pulses containing between 10**7 and 10**9 antiprotons. The first of these monitors was a parallel plate ionization chamber operated at gas pressure P=65 mbar. The other was a secondary electron emission detector, and was operated in the ultra-high vacuum of the AD. Both designs may be useful in medical and commercial applications. The position-sensitive electrodes in these detectors were manufactured by a novel method in which a laser trimmer was used to cut strip patterns on metallized polyester foils.

  16. The ASACUSA experiment at CERN's AD antiproton decelerator catches antiprotons in helium, where the antiprotons replace electrons, giving exotics atoms.

    CERN Multimedia

    Loïez, P

    2000-01-01

    Photo 03: Laser beams are prepared for shooting at antiprotonic helium atoms. Left to right: Masaki Hori (Tokyo University) and John Eades (CERN). Photo 01: Dye laser triggered by "YAG" laser. Photo 02: Masaki Hori adjusting optical system of laser beams.

  17. A measurement of the top quark mass in 1.96 TeV proton-antiproton collisions using a novel matrix element method

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, John C [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    A measurement of the top quark mass in t$\\bar{t}$ → l + jets candidate events, obtained from p$\\bar{p}$ collisions at √s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncertainty of the jet momentum reconstruction. As with all matrix elements techniques, the method involves an integration using the Standard Model matrix element for tt production and decay. however, the technique presented is unique in that the matrix element is modified to compensate for kinematic assumptions which are made to reduce computation time. Background events are dealt with through use of an event observable which distinguishes signal from background, as well as through a cut on the value of an event's maximum likelihood. Results are based on a 955 pb-1 data sample, using events with a high-pT lepton and exactly four high-energy jets, at least one of which is tagged as coming from a b quark; 149 events pass all the selection requirements. They find Mmeas = 169.8 ± 2.3(stat.) ± 1.4(syst.) GeV/c2.

  18. A Measurement of the Top Quark Mass in 1.96 TeV Proton-Antiproton Collisions Using a Novel Matrix Element Method

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, John [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    A measurement of the top quark mass in t$\\bar{t}$ → l + jets candidate events, obtained from p$\\bar{p}$ collisions at √s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncertainty of the jet momentum reconstruction. As with all matrix element techniques, the method involves an integration using the Standard Model matrix element for t$\\bar{t}$ production and decay. However, the technique presented is unique in that the matrix element is modified to compensate for kinematic assumptions which are made to reduce computation time. Background events are dealt with through use of an event observable which distinguishes signal from background, as well as through a cut on the value of an event's maximum likelihood. Results are based on a 955 pb-1 data sample, using events with a high-pT lepton and exactly four high-energy jets, at least one of which is tagged as coming from a b quark; 149 events pass all the selection requirements. They find Mmeas = 169.8 ± 2.3(stat.) ± 1.4(syst.) GeV/c2.

  19. SU-E-T-282: Dose Measurements with An End-To-End Audit Phantom for Stereotactic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R; Artschan, R [Calvary Mater Newcastle, Newcastle, NSW (Australia); Thwaites, D [University of Sydney, Sydney, NSW (Australia); Lehmann, J [Calvary Mater Newcastle, Newcastle, NSW (Australia); University of Sydney, Sydney, NSW (Australia)

    2015-06-15

    Purpose: Report on dose measurements as part of an end-to-end test for stereotactic radiotherapy, using a new audit tool, which allows audits to be performed efficiently either by an onsite team or as a postal audit. Methods: Film measurements have been performed with a new Stereotactic Cube Phantom. The phantom has been designed to perform Winston Lutz type position verification measurements and dose measurements in one setup. It comprises a plastic cube with a high density ball in its centre (used for MV imaging with film or EPID) and low density markers in the periphery (used for Cone Beam Computed Tomography, CBCT imaging). It also features strategically placed gold markers near the posterior and right surfaces, which can be used to calculate phantom rotations on MV images. Slit-like openings allow insertion of film or other detectors.The phantom was scanned and small field treatment plans were created. The fields do not traverse any inhomogeneities of the phantom on their paths to the measurement location. The phantom was setup at the delivery system using CBCT imaging. The calculated treatment fields were delivered, each with a piece of radiochromic film (EBT3) placed in the anterior film holder of the phantom. MU had been selected in planning to achieve similar exposures on all films. Calibration films were exposed in solid water for dose levels around the expected doses. Films were scanned and analysed following established procedures. Results: Setup of the cube showed excellent suitability for CBCT 3D alignment. MV imaging with EPID allowed for clear identification of all markers. Film based dose measurements showed good agreement for MLC created fields down to 0.5 mm × 0.5 mm. Conclusion: An end-to-end audit phantom for stereotactic radiotherapy has been developed and tested.

  20. Measurement of W + γ Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, Naho [Okayama Univ. (Japan)

    2005-03-01

    The production cross section and the kinematic properties of the decay products of Wγ in the W → μv decay channel from p$\\bar{p}$ collisions at √s = 1.96 TeV are presented. The measurement use the high pT muon data from the upgraded Collider Detector at Fermilab (CDF). The data were collected between March 2002 and September 2003. The total integrated luminosities are 192 pb-1 with the muon detector which covers the pseudorapidity region of |η| ≤ 0.6 and 175 pb-1 with the muon detector covering the region 0.6 ≤ |η| ≤ 1.0. In the Standard Model the μvγ final states occur due to Wγ → μvγ production and via muon Bremsstrahlung, W → μv → μvγ. W bosons are selected in their muon decay mode. Additionally, photons with transverse energy above 7 GeV, pseudorapidity in the central region (|η| < 1.1) and muon-photon angular separation ΔR(μ,γ) > 0.7 are selected. The author observes a total of 128 Wγ candidates, whereas the Standard Model expectation is 142.4 ± 9.5 events. The Wγ production cross section is found to be σ(p$\\bar{p}$ → μvγ) = 16.3 ± 2.3(stat.) ± 1.8(syst.) ± 1.2(lum.) [pb]. The theoretical prediction for this cross section is σ(p$\\bar{p}$ → lvγ) = 19.3 ± 1.4(th.) [pb]. The Standard Model predictions for several kinematic + variables are compared with data for ETγ > 7 GeV and ΔR(μ,γ) > 0.7. The measured cross section and the photon and W boson production kinematics are found to agree with the Standard Model predictions.

  1. Measurements of the B Production Cross Section in Proton-Antiproton Collisions at √s = 1.96 TeV using semileptonic decays of b hadrons

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, James Alexander [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2006-07-01

    The authors present a measurement of the cross section of b hadron (Hb) production in p$\\bar{p}$ collisions at √s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron. They use 83 pb-1 of data taken between october 2002 and May 2003 that was collected with a trigger sensitive to high momentum muons and displaced tracks. They use partially reconstructed decays in the following modes: Hb → μ- $\\bar{v}$μD0X, D0 → K-π+, and Hb → μ-$\\bar{v}$μD*+ X, D*+ → D0π+, D0 → K- π+, and their charge conjugates. They correct for the backgrounds from c$\\bar{c}$ and b$\\bar{b}$ decays, for trigger and reconstruction efficiencies, and for detector acceptance. They report the total cross section above a minimum transverse momentum (pT) of 9 GeV/c for the rapidity range |y| ≤ 0.6.

  2. Centrifugal separation and equilibration dynamics in an electron-antiproton plasma

    CERN Document Server

    Andresen, G B; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D; Butler, Eoin; Cesar, Claudio L; Chapman, Steven; Charlton, Michael; Deller, A; Eriksson, S; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C; Gill, David R; Gutierrez, A; Hangst, Jeffrey S; Hardy, Walter N; Hayden, Michael E; Humphries, Andrew J; Hydomako, Richard; Jonsell, Svante; Madsen, Niels; Menary, Scott; Nolan, Paul; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Silveira, Daniel M; So, Chukman; Storey, James W; Thompson, Robert I; van der Werf, Dirk P; Wurtele, Jonathan S; Yamazaki, Yasunori

    2011-01-01

    Charges in cold, multiple-species, non-neutral plasmas separate radially by mass, forming centrifugally-separated states. Here, we report the first detailed measurements of such states in an electron-antiproton plasma, and the first observations of the separation dynamics in any centrifugally-separated system. While the observed equilibrium states are expected and in agreement with theory, the equilibration time is approximately constant over a wide range of parameters, a surprising and as yet unexplained result. Electron-antiproton plasmas play a crucial role in antihydrogen trapping experiments.

  3. Proton-Antiproton Pair Production in Two-Photon Collisions at LEP

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hakobyan, R S; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2003-01-01

    The reaction e+e- -> e+e- proton antiproton is studied with the L3 detector at LEP. The analysis is based on data collected at e+e- center-of-mass energies from 183 GeV to 209 GeV, corresponding to an integrated luminosity of 667 pb-1. The gamma gamma -> proton antiproton differential cross section is measured in the range of the two-photon center-of-mass energy from 2.1 GeV to 4.5 GeV. The results are compared to the predictions of the three-quark and quark-diquark models.

  4. Neutron measurements with ultra-thin 3D silicon sensors in a radiotherapy treatment room using a Siemens PRIMUS linac

    Science.gov (United States)

    Guardiola, C.; Gómez, F.; Fleta, C.; Rodríguez, J.; Quirion, D.; Pellegrini, G.; Lousa, A.; Martínez-de-Olcoz, L.; Pombar, M.; Lozano, M.

    2013-05-01

    The accurate detection and dosimetry of neutrons in mixed and pulsed radiation fields is a demanding instrumental issue with great interest both for the industrial and medical communities. In recent studies of neutron contamination around medical linacs, there is a growing concern about the secondary cancer risk for radiotherapy patients undergoing treatment in photon modalities at energies greater than 6 MV. In this work we present a promising alternative to standard detectors with an active method to measure neutrons around a medical linac using a novel ultra-thin silicon detector with 3D electrodes adapted for neutron detection. The active volume of this planar device is only 10 µm thick, allowing a high gamma rejection, which is necessary to discriminate the neutron signal in the radiotherapy peripheral radiation field with a high gamma background. Different tests have been performed in a clinical facility using a Siemens PRIMUS linac at 6 and 15 MV. The results show a good thermal neutron detection efficiency around 2% and a high gamma rejection factor.

  5. Collisions of antiprotons with hydrogen molecular ions

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2009-01-01

    Time-dependent close-coupling calculations of the ionization and excitation cross section for antiproton collisions with molecular hydrogen ions are performed in an impact energy range from 0.5 keV to 10 MeV. The Born-Oppenheimer and Franck-Condon approximations as well as the impact parameter...

  6. Status Report for Experiment AD-4/ACE Biological Effectiveness of Antiproton Annihilation

    CERN Document Server

    Holzscheiter, M H; Angelopoulos, Angelo; Bassler, Niels; Beyer, Gerd; Currell, Fred; De Marco, John; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Kavanagh, Joy; Iwamoto, Kei; Jäkel, Oliver; Kantemiris, Ioannis; Knudsen, Helge; Kovacevic, Sandra; McBride, Bill; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen; Ratib, Osman; Schettino, Giuseppe; Timson, David; Singers-Sørensen, Brita; Solberg, Timothy; Vranjes, Sanja; Wouters, Brad

    2009-01-01

    Status report for experiment AD-4/ACE showing recent progress in RBE measurements for V79 Chinese Hamster cells irradiated with antiprotons. Also discussed are initial test experiments using the H2AX assay to study DNA damage to cells and initial experiments using liquid ionization chambers.

  7. Antiproton-nucleus interactions at 5 to 9 GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Bonner, B.E. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Buchanan, J.A. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Chan, C.S. (City Coll. of New York, NY (United States)); Clement, J.M. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Eiseman, S.E. (Brookhaven National Lab., Upton, NY (United States)); Empl, A. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Etkin, A. (Brookhaven National Lab., Upton, NY (United States)); Foley, K.J. (Brookhaven National Lab., Upton, NY (United States)); Hackenburg, R.W. (Brookhaven National Lab., Upton, NY (United States)); Hallman, T.J. (Johns Hopkins Univ., Baltimore, MD (United States)); Kramer, M.A. (City Coll. of New York, NY (United States)); Kruk, J. (T.W. Bonner Nuclear Lab., Rice Univ., Houston, TX (United States)); Lindenbaum, S.J. (City Coll. of New York, NY (; E854 Collaboration

    1993-06-07

    Antiproton beams of 5, 7 and 9 GeV/c were used to interact with C, Al, Cu, Sn and Pb nuclear targets. Charged particle multiplicity distributions, strange particle production cross sections and rapidity distributions were measured. The charged particle multiplicities are reported in this paper. (orig.)

  8. Conceptual Design of an Antiproton Generation and Storage Facility

    Energy Technology Data Exchange (ETDEWEB)

    Peggs, Stephen

    2006-10-24

    The Antiproton Generation and Storage Facility (AGSF) creates copious quantities of antiprotons, for bottling and transportation to remote cancer therapy centers. The first step in the generation and storage process is to accelerate an intense proton beam down the Main Linac for injection into the Main Ring, which is a Rapid Cycling Synchrotron that accelerates the protons to high energy. The beam is then extracted from the ring into a transfer line and into a Proton Target. Immediately downstream of the target is an Antiproton Collector that captures some of the antiprotons and focuses them into a beam that is transported sequentially into two antiproton rings. The Precooler ring rapidly manipulates antiproton bunches from short and broad (in momentum) to long and thin. It then performs some preliminary beam cooling, in the fraction of a second before the next proton bunch is extracted from the Main Ring. Pre-cooled antiprotons are passed on to the Accumulator ring before the next antiprotons arrive from the target. The Accumulator ring cools the antiprotons, compressing them into a dense state that is convenient for mass storage over many hours. Occasionally the Accumulator ring decelerates a large number of antiprotons, injecting them into a Deceleration Linac that passes them into a waiting Penning trap.

  9. Study of doubly strange systems using stored antiprotons

    Science.gov (United States)

    Singh, B.; Erni, W.; Krusche, B.; Steinacher, M.; Walford, N.; Liu, B.; Liu, H.; Liu, Z.; Shen, X.; Wang, C.; Zhao, J.; Albrecht, M.; Erlen, T.; Fink, M.; Heinsius, F.; Held, T.; Holtmann, T.; Jasper, S.; Keshk, I.; Koch, H.; Kopf, B.; Kuhlmann, M.; Kümmel, M.; Leiber, S.; Mikirtychyants, M.; Musiol, P.; Mustafa, A.; Pelizäus, M.; Pychy, J.; Richter, M.; Schnier, C.; Schröder, T.; Sowa, C.; Steinke, M.; Triffterer, T.; Wiedner, U.; Ball, M.; Beck, R.; Hammann, C.; Ketzer, B.; Kube, M.; Mahlberg, P.; Rossbach, M.; Schmidt, C.; Schmitz, R.; Thoma, U.; Urban, M.; Walther, D.; Wendel, C.; Wilson, A.; Bianconi, A.; Bragadireanu, M.; Caprini, M.; Pantea, D.; Patel, B.; Czyzycki, W.; Domagala, M.; Filo, G.; Jaworowski, J.; Krawczyk, M.; Lisowski, E.; Lisowski, F.; Michałek, M.; Poznański, P.; Płażek, J.; Korcyl, K.; Kozela, A.; Kulessa, P.; Lebiedowicz, P.; Pysz, K.; Schäfer, W.; Szczurek, A.; Fiutowski, T.; Idzik, M.; Mindur, B.; Przyborowski, D.; Swientek, K.; Biernat, J.; Kamys, B.; Kistryn, S.; Korcyl, G.; Krzemien, W.; Magiera, A.; Moskal, P.; Psyzniak, A.; Rudy, Z.; Salabura, P.; Smyrski, J.; Strzempek, P.; Wronska, A.; Augustin, I.; Böhm, R.; Lehmann, I.; Nicmorus Marinescu, D.; Schmitt, L.; Varentsov, V.; Al-Turany, M.; Belias, A.; Deppe, H.; Dzhygadlo, R.; Ehret, A.; Flemming, H.; Gerhardt, A.; Götzen, K.; Gromliuk, A.; Gruber, L.; Karabowicz, R.; Kliemt, R.; Krebs, M.; Kurilla, U.; Lehmann, D.; Löchner, S.; Lühning, J.; Lynen, U.; Orth, H.; Patsyuk, M.; Peters, K.; Saito, T.; Schepers, G.; Schmidt, C. J.; Schwarz, C.; Schwiening, J.; Täschner, A.; Traxler, M.; Ugur, C.; Voss, B.; Wieczorek, P.; Wilms, A.; Zühlsdorf, M.; Abazov, V. M.; Alexeev, G.; Arefiev, A.; Astakhov, V. I.; Barabanov, M. Yu.; Batyunya, B. V.; Davydov, Yu. I.; Dodokhov, V. Kh.; Efremov, A. A.; Fechtchenko, A.; Fedunov, A. G.; Galoyan, A.; Grigoryan, S.; Koshurnikov, E. K.; Lobanov, V. I.; Lobanov, Y. Yu.; Makarov, A. F.; Malinina, L. V.; Malyshev, V. L.; Olshevskiy, A.; Perevalova, E.; Piskun, A. A.; Pocheptsov, T.; Pontecorvo, G.; Rodionov, V.; Rogov, Y.; Salmin, R.; Samartsev, A.; Sapozhnikov, M. G.; Shabratova, G.; Skachkov, N. B.; Skachkova, A. N.; Strokovsky, E. A.; Suleimanov, M.; Teshev, R.; Tokmenin, V.; Uzhinsky, V.; Vodopyanov, A.; Zaporozhets, S. A.; Zhuravlev, N. I.; Zorin, A. G.; Branford, D.; Glazier, D.; Watts, D.; Böhm, M.; Britting, A.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Dobbs, S.; Seth, K.; Tomaradze, A.; Xiao, T.; Bettoni, D.; Carassiti, V.; Cotta Ramusino, A.; Dalpiaz, P.; Drago, A.; Fioravanti, E.; Garzia, I.; Savriè, M.; Akishina, V.; Kisel, I.; Kozlov, G.; Pugach, M.; Zyzak, M.; Gianotti, P.; Guaraldo, C.; Lucherini, V.; Bersani, A.; Bracco, G.; Macri, M.; Parodi, R. F.; Biguenko, K.; Brinkmann, K.; Di Pietro, V.; Diehl, S.; Dormenev, V.; Drexler, P.; Düren, M.; Etzelmüller, E.; Galuska, M.; Gutz, E.; Hahn, C.; Hayrapetyan, A.; Kesselkaul, M.; Kühn, W.; Kuske, T.; Lange, J. S.; Liang, Y.; Metag, V.; Nanova, M.; Nazarenko, S.; Novotny, R.; Quagli, T.; Reiter, S.; Rieke, J.; Rosenbaum, C.; Schmidt, M.; Schnell, R.; Stenzel, H.; Thöring, U.; Ullrich, M.; Wagner, M. N.; Wasem, T.; Wohlfarth, B.; Zaunick, H.; Ireland, D.; Rosner, G.; Seitz, B.; Deepak, P. N.; Kulkarni, A.; Apostolou, A.; Babai, M.; Kavatsyuk, M.; Lemmens, P.; Lindemulder, M.; Loehner, H.; Messchendorp, J.; Schakel, P.; Smit, H.; Tiemens, M.; van der Weele, J. C.; Veenstra, R.; Vejdani, S.; Dutta, K.; Kalita, K.; Kumar, A.; Roy, A.; Sohlbach, H.; Bai, M.; Bianchi, L.; Büscher, M.; Cao, L.; Cebulla, A.; Dosdall, R.; Gillitzer, A.; Goldenbaum, F.; Grunwald, D.; Herten, A.; Hu, Q.; Kemmerling, G.; Kleines, H.; Lehrach, A.; Nellen, R.; Ohm, H.; Orfanitski, S.; Prasuhn, D.; Prencipe, E.; Pütz, J.; Ritman, J.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Sterzenbach, G.; Stockmanns, T.; Wintz, P.; Wüstner, P.; Xu, H.; Zambanini, A.; Li, S.; Li, Z.; Sun, Z.; Xu, H.; Rigato, V.; Isaksson, L.; Achenbach, P.; Corell, O.; Denig, A.; Distler, M.; Hoek, M.; Karavdina, A.; Lauth, W.; Liu, Z.; Merkel, H.; Müller, U.; Pochodzalla, J.; Schlimme, S.; Sfienti, C.; Thiel, M.; Ahmadi, H.; Ahmed, S.; Bleser, S.; Capozza, L.; Cardinali, M.; Dbeyssi, A.; Deiseroth, M.; Feldbauer, F.; Fritsch, M.; Fröhlich, B.; Jasinski, P.; Kang, D.; Khaneft, D.; Klasen, R.; Leithoff, H. H.; Lin, D.; Maas, F.; Maldaner, S.; Martìnez Rojo, M.; Marta, M.; Michel, M.; Mora Espì, M. C.; Morales Morales, C.; Motzko, C.; Nerling, F.; Noll, O.; Pflüger, S.; Pitka, A.; Rodríguez Piñeiro, D.; Sanchez Lorente, A.; Steinen, M.; Valente, R.; Weber, T.; Zambrana, M.; Zimmermann, I.; Fedorov, A.; Korjik, M.; Missevitch, O.; Boukharov, A.; Malyshev, O.; Marishev, I.; Balanutsa, P.; Balanutsa, V.; Chernetsky, V.; Demekhin, A.; Dolgolenko, A.; Fedorets, P.; Gerasimov, A.

    2016-10-01

    Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the P ‾ ANDA experiment at FAIR. For the first time, high resolution γ-spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ--atoms will be feasible and even the production of Ω--atoms will be within reach. The latter might open the door to the | S | = 3 world in strangeness nuclear physics, by the study of the hadronic Ω--nucleus interaction. For the first time it will be possible to study the behavior of Ξ‾+ in nuclear systems under well controlled conditions.

  10. Neutron spectral measurements in an intense photon field associated with a high-energy x-ray radiotherapy machine.

    Science.gov (United States)

    Holeman, G R; Price, K W; Friedman, L F; Nath, R

    1977-01-01

    High-energy x-ray radiotherapy machines in the supermegavoltage region generate complex neutron energy spectra which make an exact evaluation of neutron shielding difficult. Fast neutrons resulting from photonuclear reactions in the x-ray target and collimators undergo successive collisions in the surrounding materials and are moderated by varying amounts. In order to examine the neutron radiation exposures quantitatively, the neutron energy spectra have been measured inside and outside the treatment room of a Sagittaire medical linear accelerator (25-MV x rays) located at Yale-New Haven Hospital. The measurements were made using a Bonner spectrometer consisting of 2-, 3-, 5-, 8-, 10- and 12-in.-diameter polyethylene spheres with 6Li and 7Li thermoluminescent dosimeter (TLD) chips at the centers, in addition to bare and cadmium-covered chips. The individual TLD chips were calibrated for neutron and photon response. The spectrometer was calibrated using a known PuBe spectrum Spectrometer measurements were made at Yale Electron Accelerator Laboratory and results compared with a neutron time-of-flight spectrometer and an activation technique. The agreement between the results from these independent methods is found to be good, except for the measurements in the direct photon beam. Quality factors have been inferred for the neutron fields inside and outside the treatment room. Values of the inferred quality factors fall primarily between 4 and 8, depending on location.

  11. Magnetic horn of the Antiproton Accumulator (AA)

    CERN Multimedia

    Photographic Service

    1988-01-01

    In the 1960s, the invention of this "current sheet lens" has helped to greatly improve the flux of neutrino beams. It was used again at the AA, collecting antiprotons from the production target at angles too large to fit into the acceptance of the AA. It was machined from aluminium to a thickness of 1.4 mm and pulsed at 400 kA for 15 microseconds (half-sine).

  12. Closing in on mass-degenerate dark matter scenarios with antiprotons and direct detection

    Energy Technology Data Exchange (ETDEWEB)

    Garny, Mathias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ibarra, Alejandro; Pato, Miguel; Vogl, Stefan [Technische Univ. Muenchen, Garching (Germany). Physik-Department

    2012-07-15

    Over the last years both cosmic-ray antiproton measurements and direct dark matter searches have proved particularly effective in constraining the nature of dark matter candidates. The present work focusses on these two types of constraints in a minimal framework which features a Majorana fermion as the dark matter particle and a scalar that mediates the coupling to quarks. Considering a wide range of coupling schemes, we derive antiproton and direct detection constraints using the latest data and paying close attention to astrophysical and nuclear uncertainties. Both signals are strongly enhanced in the presence of degenerate dark matter and scalar masses, but we show that the effect is especially dramatic in direct detection. Accordingly, the latest direct detection limits take the lead over antiprotons. We find that antiproton and direct detection data set stringent lower limits on the mass splitting, reaching 19% at a 300 GeV dark matter mass for a unity coupling. Interestingly, these limits are orthogonal to ongoing collider searches at the Large Hadron Collider, making it feasible to close in on degenerate dark matter scenarios within the next years.

  13. Antiproton nucleus potentials from global fits to antiprotonic X-rays and radiochemical data

    Science.gov (United States)

    Friedman, E.; Gal, A.; Mareš, J.

    2005-11-01

    We report on global fits of optical-model parameters to 90 data points for p¯ X-rays and 17 data points of radiochemical data put together. By doing separate fits to the two kinds of data it is possible to determine phenomenologically the radial region where the absorption of antiprotons takes place and to obtain neutron densities which represent the average behaviour over the periodic table. A finite-range attractive and absorptive p¯-nuclear isoscalar potential fits the data well. Self-consistent dynamical calculations within the RMF model demonstrate that the polarization of the nucleus by the atomic antiproton is negligible.

  14. Development and evaluation of an instrument to measure health-related quality of life in Cuban breast cancer patients receiving radiotherapy.

    Science.gov (United States)

    Lugo, Josefina; Nápoles, Misleidy; Pérez, Inés; Ordaz, Niurka; Luzardo, Mario; Fernández, Leticia

    2014-01-01

    INTRODUCTION Although modern technology has extended the survival of breast cancer patients, treatment's adverse effects impact their health-related quality of life. Currently, no instrument exists capable of identifying the range of problems affecting breast cancer patients receiving radiotherapy in Cuba's socioeconomic and cultural context. OBJECTIVES Construct and validate an instrument to measure the effects of breast cancer and radiotherapy on health-related quality of life in Cuban patients. METHODS The study was conducted at the Oncology and Radiobiology Institute, Havana, Cuba, from January 2010 through December 2011. Inclusion criteria were: adult female, histological diagnosis of breast cancer, treated with ambulatory radiotherapy, and written informed consent; patients unable to communicate orally or in writing, or who had neurologic or psychiatric conditions were excluded. Development phase: focus groups guided by a list of questions were carried out with 50 women. The patients reported 61 problems affecting their health-related quality-of-life. A nominal group (six oncologists and two nurses) identified the same problems. A syntactic analysis of the information was performed to create items for study and measurement scales. Content validity was determined by a nominal group of seven experts using professional judgment. Another 20 patients were selected to evaluate face validity. Validation phase: the instrument was applied to 230 patients at three different points: before radiotherapy, at the end of radiotherapy and four weeks after radiotherapy was concluded. Reliability, construct validity, discriminant validity, predictive validity, interpretability and response burden were evaluated. RESULTS The final instrument developed had 33 items distributed in 4 domains: physical functioning, psychological functioning, social and family relationships, and physical and emotional adverse effects of disease and treatment. There were two discrete items: perceived

  15. Antineutron and antiproton nuclear interactions at very low energies

    Science.gov (United States)

    Friedman, E.

    2014-05-01

    Experimental annihilation cross sections of antineutrons and antiprotons at very low energies are compared. Features of Coulomb focusing are observed for pbar annihilation on protons. Direct comparisons for heavier targets are not straightforward due to lack of overlap between targets and energies of experimental results for pbar and nbar. Nevertheless, the annihilation cross sections for nbar on nuclei cannot be described by an optical potential that fits well all the available data on pbar interactions with nuclei. Comparisons made with the help of this potential reveal in the nbar data features similar to Coulomb focusing. Direct comparisons between nbar and pbar annihilations at very low energies would be possible when pbar cross sections are measured on the same targets and at the same energies as the available cross sections for nbar. Such measurements may be possible in the foreseeable future.

  16. Significant negative impact of adjuvant chemotherapy on Health-Related Ouality of Life (HR-OoL) in women with breast cancer treated by conserving surgery and postoperative 3-D radiotherapy. A prospective measurement

    Energy Technology Data Exchange (ETDEWEB)

    Galalae, R.M.; Michel, J.; Kimmig, B. [Clinic for Radiation Therapy (Radiooncology), Univ. Hospital Schleswig-Holstein, Campus Kiel (Germany); Siebmann, J.U.; Kuechler, T.; Eilf, K. [Dept. of General and Thoracic Surgery/Reference Center on Quality of Life in Oncology, Univ. Hospital Schleswig-Holstein, Campus Kiel (Germany)

    2005-10-01

    Purpose: to prospectively assess health-related quality of life (HR-QoL) in women after conserving surgery for breast cancer during/after postoperative 3-D radiotherapy. Patients and methods: 109 consecutively treated patients were analyzed. HR-QoL was assessed at initiation (t1), end (t2), and 6 weeks after radiotherapy (t3) using the EORTC modules QLQ-C30/BR23. Patients were divided into three therapy groups. Group I comprised 41 patients (radiotherapy and adjuvant chemotherapy), group II 45 patients (radiotherapy and adjuvant hormonal therapy), and group III 23 patients (radiotherapy alone). Reliability was tested. Scale means were calculated. Univariate (ANOVA) and multivariate (MANCOVA) analyses were performed. Results: reliability testing revealed mean Cronbach's {alpha} > 0.70 at all measurement points. ANOVA/MANCOVA statistics revealed significantly better HR-QoL for patients in group II versus I. Patients receiving radiotherapy alone (group III) showed the best results in HR-QoL. However, scale mean differences between groups II and III were not significant. Conclusion: HR-QoL measurement using EORTC instruments during/after radiotherapy is reliable. Adjuvant chemotherapy significantly lowered HR-QoL versus hormones or radiotherapy alone. Chemotherapy patients did not recover longitudinally (from t1 to t3). (orig.)

  17. Radiation dose measurements during kilovoltage-cone beam computed tomography imaging in radiotherapy

    Directory of Open Access Journals (Sweden)

    A Sathish Kumar

    2016-01-01

    Conclusion: Radiation dose to the eye, breast, and the surface of the pelvis have been arrived at during CBCT. The doses measured on patients agreed closely with those measured on humanoid phantom and with published values.

  18. The Information Needs of New Radiotherapy Patients: How to Measure? Do They Want to Know Everything? And if Not, Why?

    Energy Technology Data Exchange (ETDEWEB)

    Zeguers, Maaike; Haes, Hanneke C.J.M. de [Department of Medical Psychology, Academic Medical Centre, Amsterdam (Netherlands); Zandbelt, Linda C. [Department of Quality and Process Innovation, Academic Medical Centre, Amsterdam (Netherlands); Hoeven, Claartje L. ter; Franssen, Sanne J. [Department of Medical Psychology, Academic Medical Centre, Amsterdam (Netherlands); Geijsen, Debbie D.; Koning, Caro C.E. [Department of Radiation Oncology, Academic Medical Centre, Amsterdam (Netherlands); Smets, Ellen M.A., E-mail: e.m.smets@amc.uva.nl [Department of Medical Psychology, Academic Medical Centre, Amsterdam (Netherlands)

    2012-01-01

    Purpose: To establish 1) further psychometric properties of the information preference for radiotherapy patients scale (IPRP); 2) what information new radiotherapy patients want to receive; 3) which patients have a lower information need. Methods and Materials: Eligible patients (n = 159; response rate 54%) of 15 radiation oncologists completed the IPRP and provided background characteristics before their first radiotherapy consultation. Exclusion criteria were: age <18 years, having undergone radiotherapy before, unable to read and write Dutch, cognitive problems or a brain tumor. Results: Reliability (Cronbach's alpha 0.84-0.97) and concurrent validity (r from .39 to .57, p < 0.001) of the subscales of the IPRP were good. New radiotherapy patients want extensive information about their disease, treatment, procedures, side effects, and prognosis (mean scores between 4.1 and 4.4 on a scale from 1 to 5) but less information about psychosocial issues (mean = 3.4). Patients who are older and male, have lung or rectal cancer, more difficulty understanding and a higher trait anxiety level, need less information. Conclusions: The IPRP can reliably and validly address information needs of patients undergoing radiation treatment. Most new radiotherapy patients want much information. Yet, information giving should be tailored according to their background, understanding and anxiety.

  19. Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker. Strong interaction studies with antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Erni, W.; Keshelashvili, I.; Krusche, B.; Steinacher, M. [Universitaet Basel, Basel (Switzerland); Heng, Y.; Liu, Z.; Liu, H.; Shen, X.; Wang, Q.; Xu, H. [Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China); Aab, A.; Albrecht, M.; Becker, J.; Csapo, A.; Feldbauer, F.; Fink, M.; Friedel, P.; Heinsius, F.H.; Held, T.; Klask, L.; Koch, H.; Kopf, B.; Leiber, S.; Leyhe, M.; Motzko, C.; Pelizaeus, M.; Pychy, J.; Roth, B.; Schroeder, T.; Schulze, J.; Sowa, C.; Steinke, M.; Trifterer, T.; Wiedner, U.; Zhong, J. [Universitaet Bochum I. Institut fuer Experimentalphysik, Bochum (Germany); Beck, R.; Bianco, S.; Brinkmann, K.T.; Hammann, C.; Hinterberger, F.; Kaiser, D.; Kliemt, R.; Kube, M.; Pitka, A.; Quagli, T.; Schmidt, C.; Schmitz, R.; Schnell, R.; Thoma, U.; Vlasov, P.; Walther, D.; Wendel, C.; Wuerschig, T.; Zaunick, H.G. [Rheinische Friedrich-Wilhelms-Universitaet Bonn, Bonn (Germany); Bianconi, A. [Universita di Brescia, Brescia (Italy); Bragadireanu, M.; Caprini, M.; Pantea, D.; Pantelica, D.; Pietreanu, D.; Serbina, L.; Tarta, P.D. [Institutul National de C and D pentru Fizica si Inginerie Nucleara ' ' Horia Hulubei' ' , Bukarest-Magurele (Romania); Kaplan, D. [IIT, Illinois Institute of Technology, Chicago (United States); Fiutowski, T.; Idzik, M.; Mindur, B.; Przyborowski, D.; Swientek, K. [AGH, University of Science and Technology, Cracow (Poland)] [and others

    2013-02-15

    This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described. (orig.)

  20. Serach for polarization effects in the antiproton production process

    CERN Multimedia

    It is proposed to study polarization effects in the production of antiprotons at the PS test beam line T11 at 3.5 GeV/c momentum. A polarization in the production process has never been studied but if existing it would allow for a rather simple and cheap way to generate a polarized antiproton beam with the existing facilities at CERN.

  1. Progress in Antiproton Production at the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Pasquinelli, Ralph J.; Drendel, Brian; Gollwitzer, Keith; Johnson, Stan; Lebedev, Valeri; Leveling, Anthony; Morgan, James; Nagaslaev, Vladimir; Peterson, Dave; Sondgeroth, Alan; Werkema, Steve; /Fermilab

    2009-04-01

    Fermilab Collider Run II has been ongoing since 2001. During this time peak luminosities in the Tevatron have increased from approximately 10 x 10{sup 30} cm{sup -2}sec{sup -1} to 300 x 10{sup 30} cm{sup 02}sec{sup -1}. A major contributing factor in this remarkable performance is a greatly improved antiproton production capability. Since the beginning of Run II, the average antiproton accumulation rate has increased from 2 x 10{sup 10}{anti p}/hr to about 24 x 10{sup 10}{anti p}/hr. Peak antiproton stacking rates presently exceed 28 x 10{sup 10}{anti p}/hr. The antiproton stacking rate has nearly doubled since 2005. It is this recent progress that is the focus of this paper. The process of transferring antiprotons to the Recycler Ring for subsequent transfer to the collider has been significantly restructured and streamlined, yielding additional cycle time for antiproton production. Improvements to the target station have greatly increased the antiproton yield from the production target. The performance of the Antiproton Source stochastic cooling systems has been enhanced by upgrades to the cooling electronics, accelerator lattice optimization, and improved operating procedures. In this paper, we will briefly report on each of these modifications.

  2. Antiproton impact ionization of atomic hydrogen and helium

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 INN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2009-11-01

    We shall present results for antiproton ionization of H and He ranging from fully differential cross sections to total ionization. The calculations have been made in a coupled pseudostate impact parameter approximation. It will be shown that the interaction between the antiproton and the target nucleus is very important at low energies.

  3. Measurement of magnetic fields produced by a "magnetic deflector" for the removal of electron contamination in radiotherapy.

    Science.gov (United States)

    Damrongkijudom, N; Oborn, B; Butson, M; Rosenfeld, A

    2006-12-01

    Electron contamination generated from interactions of x-rays with components in a medical linear accelerator's head can increase damage to skin and subcutaneous tissue during radiotherapy through increased dose deposition. Skin and subcutaneous dose from high energy x-rays can be reduced using magnetic fields to sweep the electron contamination away from the radiation treatment field. This work is aimed at investigating the magnetic fields generated by an improved magnetic deflector which utilizes Nd2Fe14B magnets. Magnetic field strengths generated by the deflector have been simulated using Vizimag 3.0 magnetic modelling software. The improved deflector has a more uniform magnetic field strength than its predecessor and is optimised to easily fit on a clinical linear accelerator. Experimental measurements of the magnetic field strengths produced have also been performed for comparison. Results show a relatively good match to Vizimag modelling in the central regions of the deflector. Reductions of skin and subcutaneous dose up to 34% of original values were seen for a 20 x 20 cm2 field at 6MV x-ray energy.

  4. Detailed analysis of observed antiprotons in cosmic rays

    Directory of Open Access Journals (Sweden)

    P Davoudifar

    2009-12-01

    Full Text Available In the present work, the origin of antiprotons observed in cosmic rays (above the atmosphere is analyzed in details. We have considered the origin of the primaries, (which their interactions with the interstellar medium is one of the most important sources of antiprotons is a supernova type II then used a diffusion model for their propagation. We have used the latest parameterization for antiproton production cross section in pp collisions (instead of well known parameterization introduced by Tan et al. as well as our calculated residence time for primaries. The resulted intensity shows the secondary antiprotons produced in pp collisions in the galaxy, have a high population as one can not consider an excess for extragalactic antiprotons. Also there is a high degree of uncertainty in different parameters.

  5. Investigation of silicon sensors for their use as antiproton annihilation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Pacifico, N., E-mail: nicola.pacifico@cern.ch [University of Bergen, Institute of Physics and Technology, Allégaten 55, 5007 Bergen (Norway); Aghion, S. [Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sez. di Milano, Via Celoria 16, 20133 Milano (Italy); Ahlén, O. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Belov, A.S. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow 117312 (Russian Federation); Bonomi, G. [University of Brescia, Department of Mechanical and Industrial Engineering, Via Branze 38, 25133 Brescia (Italy); Istituto Nazionale di Fisica Nucleare, Sez. di Pavia, Via Agostino Bassi 6, 27100 Pavia (Italy); Bräunig, P. [Kirchhoff Institute for Physics, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany); Bremer, J. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Brusa, R.S. [Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Trento (Italy); INFN-TIFPA, via Sommarive 14, 38123 Povo, Trento (Italy); Burghart, G. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Cabaret, L. [Laboratoire Aimé Cotton, CNRS, Université Paris Sud, ENS Cachan, Bâtiment 505, Campus d' Orsay, 91405 Orsay Cedex (France); Caccia, M. [University of Insubria, Dipartimento di Scienza ed Alta Tecnologia, via Valleggio 11, Como (Italy); Canali, C. [University of Zurich, Physics Institute, Winterthurerstrasse 190, 8057 Zurich (Switzerland); Caravita, R. [Istituto Nazionale di Fisica Nucleare, Sez. di Genova, Via Dodecaneso 33, 16146 Genova (Italy); University of Genoa, Department of Physics, Via Dodecaneso 33, 16146 Genova (Italy); Castelli, F. [University of Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); and others

    2014-11-21

    We present here a new application of silicon sensors aimed at the direct detection of antinucleons annihilations taking place inside the sensor's volume. Such detectors are interesting particularly for the measurement of antimatter properties and will be used as part of the gravity measurement module in the AEg{sup ¯}IS experiment at the CERN Antiproton Decelerator. One of the goals of the AEg{sup ¯}IS experiment is to measure the gravitational acceleration of antihydrogen with 1% precision. Three different silicon sensor geometries have been tested with an antiproton beam to investigate their properties as annihilation detection devices: strip planar, 3D pixels and monolithic pixel planar. In all cases we were successfully detecting annihilations taking place in the sensor and we were able to make a first characterization of the clusters and tracks.

  6. Radiotherapy; Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wannenmacher, M. [Heidelberg Univ., Mannheim (Germany). Abt. fuer Klinische Radiologie; Debus, J. [Univ. Heidelberg (Germany). Abt. Radioonkologie und Strahlentherapie; Wenz, F. (eds.) [Universitaetsklinikum Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2006-07-01

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy.

  7. Buffer-gas cooling of antiprotonic helium to 1.5 to 1.7 K, and antiproton-to–electron mass ratio

    CERN Document Server

    Hori, Masaki; Sótér, Anna; Barna, Daniel; Dax, Andreas; Hayano, Ryugo; Kobayashi, Takumi; Murakami, Yohei; Todoroki, Koichi; Yamada, Hiroyuki; Horváth, Dezső; Venturelli, Luca

    2016-01-01

    Charge, parity, and time reversal (CPT) symmetry implies that a particle and its antiparticle have the same mass. The antiproton-to-electron mass ratio Embedded Image can be precisely determined from the single-photon transition frequencies of antiprotonic helium. We measured 13 such frequencies with laser spectroscopy to a fractional precision of 2.5 × 10−9 to 16 × 10−9. About 2 × 109 antiprotonic helium atoms were cooled to temperatures between 1.5 and 1.7 kelvin by using buffer-gas cooling in cryogenic low-pressure helium gas; the narrow thermal distribution led to the observation of sharp spectral lines of small thermal Doppler width. The deviation between the experimental frequencies and the results of three-body quantum electrodynamics calculations was reduced by a factor of 1.4 to 10 compared with previous single-photon experiments. From this, Embedded Image was determined as 1836.1526734(15), which agrees with a recent proton-to-electron experimental value within 8 × 10−10.

  8. Antiproton-Proton Glory Scattering

    CERN Multimedia

    2002-01-01

    This experiment measures @*p and K|-p backwards scattering between 8 and 16 GeV/c in the Omega spectrometer using the S1 beam, with sensitivities of several events per nanobarn. The mechanism responsible for backward scattering in channels not mediated by particle exchange is not understood, and could be almost energy-independent glory scattering, especially since relatively high cross sections of 190~(@*p) and 120~(K|-p)nb have been measured earlier at 5~GeV/c. @p|-p backwards scattering is measured for monitoring purposes. The trigger requires a forward particle of momentum close to the beam momentum. Absence of light in the two forward Cerenkov counters indicates that the particle is a proton. Combinations of an incident @p|- and an outgoing K|+, or an incident K|- or @* and an outgoing @p|+, cover the following byproducts: @*p~@A~@p|+@p|- which is an (allowed) baryon exchange reaction, and the exotic exchange reactions @p|-p~@A~K|+Y K|-p~@A~@p|+Y|-, where Y|- may be the @S|- or the Y*|-(1385).

  9. Antiproton Production in 11.5A GeV/c Au+Pb Nucleus-Nucleus Collisions

    Energy Technology Data Exchange (ETDEWEB)

    De Cataldo, G.; Giglietto, N.; Raino, A.; Spinelli, P. [University of Bari/INFN, Bari (Italy); Dover, C.B. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Huang, H.Z. [University of California at Los Angeles, Los Angeles, California 90024 (United States); Hill, J.C.; Libby, B.; Wohn, F.K. [Iowa State University, Ames, Iowa 50011 (United States); Rabin, M.S. [University of Massachusetts, Amherst, Massachusetts 01003 (United States); Haridas, P.; Pless, I.A.; Van Buren, G. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Armstrong, T.A.; Lewis, R.A.; Reid, J.D.; Smith, G.A.; Toothacker, W.S. [Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Davies, R.; Hirsch, A.S.; Porile, N.T.; Rimai, A.; Scharenberg, R.P.; Srivastava, B.K.; Tincknell, M.L. [Purdue University, West Lafayette, Indiana 47907 (United States); Greene, S.V. [Vanderbilt University, Nashville, Tennessee 37235 (United States); Bennett, S.J.; Cormier, T.M.; Dee, P.; Fachini, P.; Kim, B.; Li, Q.; Li, Y.; Munhoz, M.G.; Pruneau, C.A.; Wilson, W.K.; Zhao, K. [Wayne State University, Detroit, Michigan 48201 (United States); Barish, K.N.; Bennett, M.J.; Chikanian, A.; Coe, S.D.; Diebold, G.E.; Finch, L.E.; George, N.K.; Kumar, B.S.; Lajoie, J.G.; Majka, R.D.; Nagle, J.L.; Pope, J.K.; Rotondo, F.S.; Sandweiss, J.; Slaughter, A.J.; Wolin, E.J. [Yale University, New Haven, Connecticut 06520 (United States)

    1997-11-01

    We present the first results from the E864 Collaboration on the production of antiprotons in 10{percent} central 11.5A GeV /c Au+Pb nucleus collisions at the Brookhaven Alternating Gradient Synchrotron. We report invariant multiplicities for antiproton production in the kinematic region 1.4{lt}y{lt}2.2 and 50{lt} p{sub T}{lt} 300 MeV/c , and compare our data with a first collision scaling model and previously published results from the E878 Collaboration. The differences between the E864 and E878 antiproton measurements and the implications for antihyperon production are discussed. {copyright} {ital 1997} {ital The American Physical Society}

  10. NOTE: Gating characteristics of an Elekta radiotherapy treatment unit measured with three types of detector

    Science.gov (United States)

    Evans, Philip M.; Symonds-Tayler, J. Richard N.; Colgan, Ruth; Hugo, Geoffrey D.; Letts, Nicky; Sandin, Carlos

    2010-04-01

    The characteristics of an Elekta Precise treatment machine with a gating interface were investigated. Three detectors were used: a Farmer ionization chamber, a MatriXX ionization chamber array and an in-house, single pulse-measurement ionization chamber (IVC). Measurements were made of dosimetric accuracy, flatness and symmetry characteristics and duty cycle for a range of beam-on times and gating periods. Results were compared with a standard ungated delivery as a reference. For all beam-on times, down to 0.5 s, dosimetric differences were below ±1% and flatness and symmetry parameter variations were below ±1.5%. For the shorter beam-on times the in-house detector deviated from the other two detectors, suggesting that this device should be used in conjunction with other detectors for absolute dosimetry purposes. However, it was found to be useful for studying gated beam characteristics pulse by pulse.

  11. Relative stopping power measurements to aid in the design of anthropomorphic phantoms for proton radiotherapy.

    Science.gov (United States)

    Grant, Ryan L; Summers, Paige A; Neihart, James L; Blatnica, Anthony P; Sahoo, Narayan; Gillin, Michael T; Followill, David S; Ibbott, Geoffrey S

    2014-03-06

    The delivery of accurate proton dose for clinical trials requires that the appropriate conversion function from Hounsfield unit (HU) to relative linear stopping power (RLSP) be used in proton treatment planning systems (TPS). One way of verifying that the TPS is calculating the correct dose is an end-to-end test using an anthropomorphic phantom containing tissue equivalent materials and dosimeters. Many of the phantoms in use for such end-to-end tests were originally designed using tissue-equivalent materials that had physical characteristics to match patient tissues when irradiated with megavoltage photon beams. The aim of this study was to measure the RLSP of materials used in the phantoms, as well as alternative materials to enable modifying phantoms for use at proton therapy centers. Samples of materials used and projected for use in the phantoms were measured and compared to the HU assigned by the treatment planning system. A percent difference in RLSP of 5% was used as the cutoff for materials deemed acceptable for use in proton therapy (i.e., proton equivalent). Until proper tissue-substitute materials are identified and incorporated, institutions that conduct end-to-end tests with the phantoms are instructed to override the TPS with the measured stopping powers we provide. To date, the RLSPs of 18 materials have been measured using a water phantom and/or multilayer ion chamber (MLIC). Nine materials were identified as acceptable for use in anthropomorphic phantoms. Some of the failing tissue substitute materials are still used in the current phantoms. Further investigation for additional appropriate tissue substitute materials in proton beams is ongoing. Until all anthropomorphic phantoms are constructed of appropriate materials, a unique HU-RLSP phantom has been developed to be used during site visits to verify the proton facility's treatment planning HU-RLSP calibration curve.

  12. Secondary emission monitor for keV ion and antiproton beams

    CERN Document Server

    Sosa, Alejandro; Bravin, Enrico; Harasimowciz, Janusz; Welsch, C P

    2013-01-01

    Beam profile monitoring of low intensity keV ion and antiproton beams remains a challenging task. A Sec- ondary electron Emission Monitor (SEM) has been de- signed to measure profiles of beams with intensities below 107 and energies as low as 20 keV. The monitor is based on a two stage microchannel plate (MCP) and a phosphor screen facing a CCD camera. Its modular design allows two different operational setups. In this contribution we present the design of a prototype and discuss results from measurements with antiprotons at the AEgIS experiment at CERN. This is then used for a characterization of the monitor with regard to its possible future use at different facilities.

  13. First experimental detection of antiproton in-flight annihilation on nuclei at 130 keV

    CERN Document Server

    Aghai-Khozani, H; Corradini, M; Hayano, R; Hori, M; Kobayashi, T; Leali, M; Lodi-Rizzini, E; Mascagna, V; Prest, M; Soter, A; Todoroki, K; Vallazza, E; Venturelli, L; Zurlo, N

    2012-01-01

    The existing data of antinucleon-nucleon and antinucleon-nuclei annihilation cross-sections are confined to energies above about 1MeV. Experimental limitations have prevented till now the lower energies data to be achieved in spite of the interest they represent for theoretical models. One of the unresolved question concerns the antiproton annihilation cross-section measured at LEAR on light nuclei in the MeV region, which show a saturation with the mass number of the target nucleus against any naive expectation. With regard to fundamental cosmology, the knowledge of the annihilation cross-sections at energies below 1MeV can contribute to understand the matter-antimatter asymmetry in the Universe. We present here the experimental demonstration of the feasibility of the measurement of antiproton-nuclei annihilation cross-sections in the 100 keV region.

  14. A practical and theoretical definition of very small field size for radiotherapy output factor measurements

    Energy Technology Data Exchange (ETDEWEB)

    Charles, P. H., E-mail: p.charles@qut.edu.au; Crowe, S. B.; Langton, C. M.; Trapp, J. V. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001 (Australia); Cranmer-Sargison, G. [Department of Medical Physics, Saskatchewan Cancer Agency, 20 Campus Dr., Saskatoon, Saskatchewan S7L 3P6, Canada and Academic Unit of Medical Physics, Faculty of Medicine and Health, University of Leeds, 8.001 Worsley Building, Leeds LS2 9JT (United Kingdom); Thwaites, D. I. [Institute of Medical Physics, School of Physics, University of Sydney, NSW 2006 (Australia); Kairn, T. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia and Premion, The Wesley Medical Centre, Suite 1, 40 Chasely St, Auchenflower, Brisbane, QLD 4066 (Australia); Knight, R. T. [Premion, The Wesley Medical Centre, Suite 1, 40 Chasely St, Auchenflower, Brisbane, QLD 4066 (Australia); Kenny, J. [The Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, 619 Lower Plenty Road, Yallambie, VIC 3085, Australia and Radiation Oncology Queensland, St Andrew' s Toowoomba Hospital, Toowoomba, QLD 4350 (Australia)

    2014-04-15

    Purpose: This work introduces the concept of very small field size. Output factor (OPF) measurements at these field sizes require extremely careful experimental methodology including the measurement of dosimetric field size at the same time as each OPF measurement. Two quantifiable scientific definitions of the threshold of very small field size are presented. Methods: A practical definition was established by quantifying the effect that a 1 mm error in field size or detector position had on OPFs and setting acceptable uncertainties on OPF at 1%. Alternatively, for a theoretical definition of very small field size, the OPFs were separated into additional factors to investigate the specific effects of lateral electronic disequilibrium, photon scatter in the phantom, and source occlusion. The dominant effect was established and formed the basis of a theoretical definition of very small fields. Each factor was obtained using Monte Carlo simulations of a Varian iX linear accelerator for various square field sizes of side length from 4 to 100 mm, using a nominal photon energy of 6 MV. Results: According to the practical definition established in this project, field sizes ≤15 mm were considered to be very small for 6 MV beams for maximal field size uncertainties of 1 mm. If the acceptable uncertainty in the OPF was increased from 1.0% to 2.0%, or field size uncertainties are 0.5 mm, field sizes ≤12 mm were considered to be very small. Lateral electronic disequilibrium in the phantom was the dominant cause of change in OPF at very small field sizes. Thus the theoretical definition of very small field size coincided to the field size at which lateral electronic disequilibrium clearly caused a greater change in OPF than any other effects. This was found to occur at field sizes ≤12 mm. Source occlusion also caused a large change in OPF for field sizes ≤8 mm. Based on the results of this study, field sizes ≤12 mm were considered to be theoretically very small for 6

  15. Probing Matter Radii of Neutron-Rich Nuclei by Antiproton Scattering

    OpenAIRE

    Lenske, H.; P. Kienle

    2005-01-01

    We propose to use antiprotons to investigate the sizes of stable and neutron-rich exotic nuclei by measurements of the $\\pbar A$ absorption cross section along isotopic chains in inverse kinematics. The expected effects are studied theoretically in a microscopic model. The $\\pbar U$ optical potentials are obtained by folding free space $\\pbar N$ scattering amplitudes with HFB ground state densities and solving the scattering equations by direct integration. The mass dependence of absorption c...

  16. Thermal and epithermal neutron fluence rate gradient measurements by PADC detectors in LINAC radiotherapy treatments-field

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, M. T., E-mail: mariate9590@gmail.com; Barros, H.; Pino, F.; Sajo-Bohus, L. [Universidad Simón Bolívar, Nuclear Physics Laboratory, Sartenejas, Caracas (Venezuela, Bolivarian Republic of); Dávila, J. [Física Médica C. A. and Universidad Central de Venezuela, Caracas (Venezuela, Bolivarian Republic of)

    2015-07-23

    LINAC VARIAN 2100 is where energetic electrons produce Bremsstrahlung radiation, with energies above the nucleon binding energy (E≈5.5MeV). This radiation induce (γ,n) and (e,e’n) reactions mainly in the natural tungsten target material (its total photoneutron cross section is about 4000 mb in a energy range from 9-17 MeV). These reactions may occur also in other components of the system (e.g. multi leaf collimator). During radiation treatment the human body may receive an additional dose inside and outside the treated volume produced by the mentioned nuclear reactions. We measured the neutron density at the treatment table using nuclear track detectors (PADC-NTD). These covered by a boron-converter are employed, including a cadmium filter, to determine the ratio between two groups of neutron energy, i.e. thermal and epithermal. The PADC-NTD detectors were exposed to the radiation field at the iso-center during regular operation of the accelerator. Neutron are determined indirectly by the converting reaction {sup 10}B(n,α){sup 7}Li the emerging charged particle leave their kinetic energy in the PADC forming a latent nuclear track, enlarged by chemical etching (6N, NaOH, 70°C). Track density provides information on the neutron density through calibration coefficient (∼1.6 10{sup 4} neutrons /track) obtained by a californium source. We report the estimation of the thermal and epithermal neutron field and its gradient for photoneutrons produced in radiotherapy treatments with 18 MV linear accelerators. It was obsered that photoneutron production have higher rate at the iso-center.

  17. NOTE Thyroid volume measurement in external beam radiotherapy patients using CT imaging: correlation with clinical and anthropometric characteristics

    Science.gov (United States)

    Veres, C.; Garsi, J. P.; Rubino, C.; Pouzoulet, F.; Bidault, F.; Chavaudra, J.; Bridier, A.; Ricard, M.; Ferreira, I.; Lefkopoulos, D.; de Vathaire, F.; Diallo, I.

    2010-11-01

    The aim of this study is to define criteria for accurate representation of the thyroid in human models used to represent external beam radiotherapy (EBRT) patients and evaluate the relationship between the volume of this organ and clinical and anthropometric characteristics. From CT images, we segmented the thyroid gland and calculated its volume for a population of 188 EBRT patients of both sexes, with ages ranging from 1 to 89 years. To evaluate uncertainties linked to measured volumes, experimental studies on the Livermore anthropomorphic phantom were performed. For our population of EBRT patients, we observed that in children, thyroid volume increased rapidly with age, from about 3 cm3 at 2 years to about 16 cm3 at 20. In adults, the mean thyroid gland volume was 23.5 ± 9 cm3 for males and 17.5 ± 8 cm3 for females. According to anthropometric parameters, the best fit for children was obtained by modeling the log of thyroid volume as a linear function of body surface area (BSA) (p < 0.0001) and age (p = 0.04) and for adults, as a linear function of BSA (p < 0.0001) and gender (p = 0.01). This work enabled us to demonstrate that BSA was the best indicator of thyroid volume for both males and females. These results should be taken into account when modeling the volume of the thyroid in human models used to represent EBRT patients for dosimetry in retrospective studies of the relationship between the estimated dose to the thyroid and long-term follow-up data on EBRT patients.

  18. Thyroid volume measurement in external beam radiotherapy patients using CT imaging: correlation with clinical and anthropometric characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Veres, C; Garsi, J P; Rubino, C; De Vathaire, F; Diallo, I [Inserm, CESP Centre for research in Epidemiology and Population Health, U1018, Radiation Epidemiology Team, F 94807, Villejuif (France); Pouzoulet, F; Bidault, F; Chavaudra, J; Bridier, A; Ricard, M; Ferreira, I; Lefkopoulos, D, E-mail: ibrahim.diallo@igr.f [Institut Gustave Roussy, F-94805, Villejuif (France)

    2010-11-07

    The aim of this study is to define criteria for accurate representation of the thyroid in human models used to represent external beam radiotherapy (EBRT) patients and evaluate the relationship between the volume of this organ and clinical and anthropometric characteristics. From CT images, we segmented the thyroid gland and calculated its volume for a population of 188 EBRT patients of both sexes, with ages ranging from 1 to 89 years. To evaluate uncertainties linked to measured volumes, experimental studies on the Livermore anthropomorphic phantom were performed. For our population of EBRT patients, we observed that in children, thyroid volume increased rapidly with age, from about 3 cm{sup 3} at 2 years to about 16 cm{sup 3} at 20. In adults, the mean thyroid gland volume was 23.5 {+-} 9 cm{sup 3} for males and 17.5 {+-} 8 cm{sup 3} for females. According to anthropometric parameters, the best fit for children was obtained by modeling the log of thyroid volume as a linear function of body surface area (BSA) (p < 0.0001) and age (p = 0.04) and for adults, as a linear function of BSA (p < 0.0001) and gender (p = 0.01). This work enabled us to demonstrate that BSA was the best indicator of thyroid volume for both males and females. These results should be taken into account when modeling the volume of the thyroid in human models used to represent EBRT patients for dosimetry in retrospective studies of the relationship between the estimated dose to the thyroid and long-term follow-up data on EBRT patients. (note)

  19. Concept for the Antiproton Production Target at FAIR

    CERN Document Server

    Knie, K; Franzke, B; Gostishchev, V; Steck, M; Sievers, P

    2012-01-01

    This report summarizes the status of the antiproton (pbar) production area at the future FAIR (Facility for Antiproton and Ion Research) complex at GSI, Darmstadt [1]. This area is composed of the pbar production target, a magnetic horn for the collection of the pbars, and the pbar separator between target and Collector Ring (CR). The emphasis is on the optimization of the accumulation rate of antiprotons to maximize the expected peak and average luminosity for the experiment. As the doses in the target area will be very high, also radiation protection issues will be addressed.

  20. Assessment of target volume doses in radiotherapy based on the standard and measured calibration curves

    Directory of Open Access Journals (Sweden)

    Gholamreza Fallah Mohammadi

    2015-01-01

    Full Text Available Context: In radiation treatments, estimation of the dose distribution in the target volume is one of the main components of the treatment planning procedure. To estimate the dose distribution, the information of electron densities is necessary. The standard curves determined by computed tomography (CT scanner that may be different from that of other oncology centers. In this study, the changes of dose calculation due to the different calibration curves (HU-ρel were investigated. Materials and Methods: Dose values were calculated based on the standard calibration curve that was predefined for the treatment planning system (TPS. The calibration curve was also extracted from the CT images of the phantom, and dose values were calculated based on this curve. The percentage errors of the calculated values were determined. Statistical Analysis Used: The statistical analyses of the mean differences were performed using the Wilcoxon rank-sum test for both of the calibration curves. Results and Discussion: The results show no significant difference for both of the measured and standard calibration curves (HU-ρel in 6, 15, and 18 MeV energies. In Wilcoxon ranked sum nonparametric test for independent samples with P < 0.05, the equality of monitor units for both of the curves to transfer 200 cGy doses to reference points was resulted. The percentage errors of the calculated values were lower than 2% and 1.5% in 6 and 15 MeV, respectively. Conclusion: From the results, it could be concluded that the standard calibration curve could be used in TPS dose calculation accurately.

  1. Psychological and physical distress of cancer patients during radiotherapy

    CERN Document Server

    König, A

    2001-01-01

    Purpose: patients undergoing radiotherapy have physical and psychological symptoms related to the underlying disease and the treatment. In order to give the best possible support to the patients, more knowledge about the amount and the changing of distress in the course of radiotherapy is of essentially importance. Methods: The distress was measured in a consecutive sample of cancer patients (n=82) undergoing radiotherapy. Each patient was given the EORTC-QLQ-C30, the HADS and a special questionnaire which ascertain radiotherapy-specific items before starting the radiotherapy, at the onset of radiotherapy, in the third week of radiotherapy and 3 weeks after the end of radiotherapy. Results: within the first week of treatment the psychological distress of the patients is increasing; 98.8 % of the patients are 'moderate distressed', 46 % 'severe distressed'. General physical symptoms seem not to be affected by the radiotherapy, there is no changing. The distress caused by the organization of the radiotherapy is...

  2. Non-dissociative and dissociative ionisation of H sub 2 by 50-2000 keV antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moeller, S.P.; Pedersen, J.O.P.; Tang-Petersen, S.; Uggerhoej, E. (Aarhus Univ. (Denmark). Inst. of Physics); Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland)); Morenzoni, E. (Paul Scherrer Inst. (PSI), Villigen (Switzerland))

    1990-08-14

    A beam of antiprotons with energies between 50 keV and 2 MeV has been used for measurements of non-dissociative ionisation and dissociative ionisation cross sections of H{sub 2}. The results are compared with cross sections for equivelocity protons and electrons, and the role of interference effects in two-electron processes is discussed. (author).

  3. Antiproton-proton Annihilation Into Two Mesons: The Role Of Relativistic Distortion

    CERN Document Server

    El-Bennich, B O

    2004-01-01

    The more than a decade old data on differential cross sections and analyzing powers in antiproton-proton annihilation into two pions (or two kaons), measured at the Low Energy Antiproton Ring (LEAR) of CERN, have stimulated several theoretical investigations. A characteristic feature of the data are the large variations of the scattering observables as a function of the scattering angle and of the laboratory energy already below 100 MeV. Amplitude analyzes reproduce the data with few partial waves (J ≤ 4) and one concludes that the annihilation process is very short- ranged and of the order of the nucleon size. Nonetheless, early models, using either baryonic or quark degrees of freedom, give rise to an even shorter antibaryon-baryon interaction failing to produce substantial higher (J ≥ 2) partial wave amplitudes and consequently to adequately describe the LEAR data. In this thesis, we systematically consider improvements within the framework of quark-line diagrams. We first derive various quar...

  4. Further studies of double ionization of He, Ne, and Ar by fast and slow antiprotons

    Science.gov (United States)

    Andersen, L. H.; Hvelplund, P.; Knudsen, H.; Møller, S. P.; Pedersen, J. O. P.; Tang-Petersen, S.; Uggerhøj, E.; Elsener, K.; Morenzoni, E.

    1989-12-01

    Measurements of the ratio R between double- and single-ionization cross sections for antiproton impact on He, Ne, and Ar targets are reported for impact energies ranging from 65 keV to 20 MeV. At high energies the results are found to merge with proton results at around 20 MeV, and the high-energy limit of the common ratio is in good agreement with recent first-Born-calculation results for the helium target. The large difference previously observed in the ratio R for protons and antiprotons at energies between 0.5 and 5 MeV is found to persist down to the lowest energies investigated here.

  5. Further studies of double ionization of He, Ne, and Ar by fast and slow antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moller, S.P.; Pedersen, J.O.P.; Tang-Petersen, S.; Uggerhoj, E. (Institute of Physics, University of Aarhus, DK-8000 Aarhus C, Denmark (Denmark)); Elsener, K. (CERN, CH-1211 Geneva 23, (Switzerland)); Morenzoni, E. (PSI, CH-5234 Villigen, (Switzerland))

    1989-12-15

    Measurements of the ratio {ital R} between double- and single-ionization cross sections for antiproton impact on He, Ne, and Ar targets are reported for impact energies ranging from 65 keV to 20 MeV. At high energies the results are found to merge with proton results at around 20 MeV, and the high-energy limit of the common ratio is in good agreement with recent first-Born-calculation results for the helium target. The large difference previously observed in the ratio {ital R} for protons and antiprotons at energies between 0.5 and 5 MeV is found to persist down to the lowest energies investigated here.

  6. A Cryogenic Current Comparator for the Low Energy Antiproton Facilities at CERN

    CERN Document Server

    Fernandes, M; Welsch, CP

    2014-01-01

    Several laboratories have shown the potential of using Superconducting QUantum Interference Device (SQUID) magnetometers together with superconductor magnetic shields to measure beam current intensities in the submicro-Ampere regime. CERN, in collaboration with GSI, Jena university and Helmholtz Institute Jena, is currently working on developing an improved version of such a current monitor for the Antiproton Decelerator (AD) and Extra Low ENergy Antiproton (ELENA) rings at CERN, aiming for better current resolution and overall system availability. This contribution will present the current design, including theoretical estimation of the current resolution; stability limits of SQUID systems and adaptation of the coupling circuit to the AD beam parameters; the analysis of thermal and mechanical cryostat modes.

  7. 10 GeV dark matter candidates and cosmic-ray antiprotons

    CERN Document Server

    Lavalle, Julien

    2010-01-01

    Recent measurements performed with some direct dark matter detection experiments, e.g. CDMS-II and CoGENT (after DAMA/LIBRA), have unveiled a few events compatible with WIMP-nuclei interactions. The preferred mass range is around 10 GeV, with a quite large spin-independent cross section of $10^{-43}-10^{-41}\\,{\\rm cm^2}$. In this letter, we recall that a light WIMP with dominant couplings to quarks should also generate cosmic-ray antiprotons. Taking advantage of recent works constraining the Galactic dark matter mass profile on the one hand and on cosmic-ray propagation on the other hand, we point out that considering a thermal annihilation cross section for such low mass candidates unavoidably results in an antiproton flux in tension with the current data, leading either to exclusion or to observable features. This should be taken into account for a consistent interpretation of direct detection signals.

  8. Scattered antiproton polarization in pp elastic scattering at 220 MeV in bubble chamber

    CERN Document Server

    Ohsugi, T

    1973-01-01

    The polarization of antiproton scattering in pp elastic collision has been measured in the four intervals of the CM scattering angle theta /sup */ less than 90 degrees by means of double scattering in a bubble chamber. The analysis has been performed on the basis of 999 double elastic events which have been found in about 100K pictures of the 81- cm Saclay hydrogen bubble chamber exposed to a 0.7 GeV/c antiproton beam from the CERN PS. The obtained values of polarization show the maximum value 0.52+or-0.19 at theta /sup */=56 degrees . The polarization for pp scattering seems to be larger than that for pp scattering. The results are also compared with the potential model by Bryan and Phillips (1968) and with the modified diffraction model by Frahn and Venter (1964). Possible systematic errors in the present experiment are discussed in detail. (17 refs).

  9. Limits on the Dark Matter from AMS-02 antiproton and positron fraction data

    CERN Document Server

    Lu, Bo-Qiang; Zong, Hong-Shi

    2015-01-01

    We derive limits on the dark matter annihilation cross section and lifetime using measurements of the AMS-02 antiproton ratio and positron fraction data. In deriving the limits, we consider the scenario of secondary particles accelerated in supernova remnants (SNRs) which has been argued to be able to reasonably account for the AMS-02 high energy positron/antiproton fraction data. We parameterize the contribution of secondary particles accelerated in SNRs and then fit the observational data within the conventional cosmic ray propagation model by adopting the GALPROP code. We use the likelihood ratio test to determine the 95$\\%$ confidence level upper limits of the possible dark matter (DM) contribution to the antiproton/positron fractions measured by AMS-02. Our limits are stronger than that set by the Fermi-LAT gamma-ray Pass 8 data of the dwarf spheroidal satellite galaxies. We also show that the solar modulation (cosmic ray propagation) parameters can play a non-negligible role in modifying the constraints...

  10. Conceptual designs for antiproton space propulsion systems

    Energy Technology Data Exchange (ETDEWEB)

    Cassenti, B.N.

    1989-01-01

    Five conceptual designs for antimatter space propulsion systems were compared in terms of their performance characteristics. The systems examined included solid-core liquid-propellant rockets; magnetically confined gaseous-core rockets using liquid or solid propellants; plasma-core rockets; pion rockets, which are driven directly by the mass annihilation products; and ram-augmented rockets, in which antiproton annihilation is used to heat hydrogen collected in interstellar space. It was found that, in general, as the specific impulse of the propulsion system increases, the thrust decreases. The comparison between designs showed that only fusion rockets have the capability to compete in performance with mass annihilation rockets. For very-high-speed interstellar missions, pion rockets, which can have a specific impulse of 20 million sec (although with a thrust-to-engine mass ratios of only 0.01 G) will offer best performance. 36 refs.

  11. Fragmentation of methane molecules by antiproton impact

    Science.gov (United States)

    Salehzadeh, Arash; Kirchner, Tom

    2016-09-01

    Extending previous work for proton impact, we have investigated the fragmentation of methane molecules due to collisions with antiprotons in the 25 keV to 5 MeV impact energy range. The multi-center nature of the problem is addressed by using a spectral representation of the molecular Hartree-Fock-level Hamiltonian and a single-center expansion of the initially populated molecular orbitals. The two-center basis generator method (TC-BGM) is used for orbital propagation. Electron-removal cross sections obtained from the TC-BGM solutions are complemented with a dynamical decay-route fragmentation model to calculate cross sections for the production of fragment ions. Good agreement with the available experimental data is observed for CH4+,CH3+,CH2+and CH+. Work supported by NSERC, Canada.

  12. The CERN Low Energy Antiproton Ring (LEAR) project

    CERN Document Server

    Lefèvre, P; Plass, G

    1980-01-01

    The idea to add to the CERN Antiproton Accumulator (AA) a facility for experiments with dense and pure beams of low energy antiprotons has received enthusiastic support from many members of the physics community. After conceptual studies done since 1977 the following scheme was authorized in May 1980: Small batches of cooled antiprotons will be skimmed off from the AA at regular intervals, decelerated in the CERN PS and transferred into a small storage ring (LEAR). In its first stage LEAR will work as a beam stretcher providing a high duty cycle spill of 10/sup 6/ p/s into an experimental area. Future options (not yet authorized) foresee internal jet targets together with cooling, co-rotating beams of p and H, proton antiproton colliding beams, fast extraction with slowing down of p's to rest. A storage ring to fulfil this variety of tasks has to combine some unusual machine features which are summarized in the present report. (6 refs).

  13. Antiproton cell experiment: antimatter is a better killer

    CERN Multimedia

    2006-01-01

    "European Organization for Nuclear Research is reporting that results from a three year study of antiprotons for neoplasm irrdiation showed a better cellular killer with a smaller lethal dose." (1,5 page)

  14. A new antiproton beam transfer scheme without coalescing

    Energy Technology Data Exchange (ETDEWEB)

    Weiren Chou et al.

    2003-06-04

    An effective way to increase the luminosity in the Fermilab Tevatron collider program Run2 is to improve the overall antiproton transfer efficiency. During antiproton coalescing in the Main Injector (MI), about 10-15% particles get lost. This loss could be avoided in a new antiproton transfer scheme that removes coalescing from the process. Moreover, this scheme would also eliminate emittance dilution due to coalescing. This scheme uses a 2.5 MHz RF system to transfer antiprotons from the Accumulator to the Main Injector. It is then followed by a bunch rotation in the MI to shorten the bunch length so that it can be captured by a 53 MHz RF bucket. Calculations and ESME simulations show that this scheme works. No new hardware is needed to implement this scheme.

  15. Density shift and broadening of transition lines in antiprotonic helium

    Science.gov (United States)

    Bakalov; Jeziorski; Korona; Szalewicz; Tchoukova

    2000-03-13

    The density shift and broadening of the transition lines of antiprotonic helium have been evaluated in the impact approximation using an interatomic potential calculated ab initio with the symmetry-adapted perturbation theory. The results help to remove an uncertainty of up to 10 ppm in the laser spectroscopy data on antiprotonic helium and are of importance in experimental tests of bound state QED and CPT invariance.

  16. Heating nuclei with 8 GeV/c antiprotons

    CERN Document Server

    Lefort, T; Hsi, W C; Beaulieu, L; Viola, V E; Pienkowski, L; Korteling, R G; Leforest, R; Martin, E; Ramakrishnan, E; Rowland, D; Ruangma, A; Winchester, E M; Yennello, S J; Gushue, S; Remsberg, L P; Back, B B; Breuer, H

    1999-01-01

    Studies of the heating effect of 8 GeV/c pi sup - and antiproton beams incident on a sup 1 sup 9 sup 7 Au nucleus have been conducted at Brookhaven AGS accelerator with the Indiana Silicon Sphere 4 pi detector array. Enhanced energy deposition for antiprotons relative to negative pions and protons in this energy regime is observed. The results are consistent with predictions of an intranuclear cascade code.

  17. Bayesian analysis of spatial-dependent cosmic-ray propagation: Astrophysical background of antiprotons and positrons

    Science.gov (United States)

    Feng, Jie; Tomassetti, Nicola; Oliva, Alberto

    2016-12-01

    The AMS-02 experiment has reported a new measurement of the antiproton/proton ratio in Galactic cosmic rays (CRs). In the energy range E ˜60 - 450 GeV , this ratio is found to be remarkably constant. Using recent data on CR proton, helium, and carbon fluxes, 10Be/9Be and B/C ratios, we have performed a global Bayesian analysis based on a Markov chain Monte Carlo sampling algorithm under a "two halo model" of CR propagation. In this model, CRs are allowed to experience a different type of diffusion when they propagate in the region close to the Galactic disk. We found that the vertical extent of this region is about 900 pc above and below the disk, and the corresponding diffusion coefficient scales with energy as D ∝E0.15 , describing well the observations on primary CR spectra, secondary/primary ratios, and anisotropy. Under this model, we have carried out improved calculations of antiparticle spectra arising from secondary CR production and their corresponding uncertainties. We made use of Monte Carlo generators and accelerator data to assess the antiproton production cross sections and their uncertainties. While the positron excess requires the contribution of additional unknown sources, we found that the new AMS-02 antiproton data are consistent, within the estimated uncertainties, with our calculations based on secondary production.

  18. Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p-Pb collisions at $\\sqrt{s_{\\rm NN}}$= 5.02 TeV

    CERN Document Server

    Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahmad, Shakeel; Ahn, Sang Un; Aiola, Salvatore; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Millan Almaraz, Jesus Roberto; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Arnaldi, Roberta; Arnold, Oliver Werner; Arsene, Ionut Cristian; Arslandok, Mesut; Audurier, Benjamin; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Balasubramanian, Supraja; Baldisseri, Alberto; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; 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Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botta, Elena; Bourjau, Christian; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Bashir Butt, Jamila; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Carnesecchi, Francesca; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Ceballos Sanchez, Cesar; Cerello, Piergiorgio; Cerkala, Jakub; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; 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Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Feuillard, Victor Jose Gaston; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Fleck, Martin Gabriel; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fronze, Gabriele Gaetano; 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; Gauger, Erin Frances; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; 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Hillemanns, Hartmut; Hippolyte, Boris; Horak, David; Hosokawa, Ritsuya; Hristov, Peter Zahariev; Huang, Meidana; Humanic, Thomas; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Ilkaev, Radiy; Inaba, Motoi; Incani, Elisa; Ippolitov, Mikhail; Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacazio, Nicolo; Jacobs, Peter Martin; Jadhav, Manoj Bhanudas; Jadlovska, Slavka; Jadlovsky, Jan; Jahnke, Cristiane; Jakubowska, Monika Joanna; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karayan, Lilit; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Do Won; Kim, Dong Jo; Kim, Daehyeok; Kim, Hyeonjoong; Kim, Jinsook; 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; Klewin, Sebastian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobdaj, Chinorat; Kofarago, Monika; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kopcik, Michal; Kostarakis, Panagiotis; Kour, Mandeep; Kouzinopoulos, Charalampos; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Koyithatta Meethaleveedu, Greeshma; Kralik, Ivan; Kravcakova, Adela; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kumar, Ajay; Kumar, Jitendra; Lokesh, Kumar; Kumar, Shyam; Kurashvili, Podist; 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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; Sefcik, Michal; Seger, Janet Elizabeth; Sekiguchi, Yuko; Sekihata, Daiki; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Senyukov, Serhiy; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shahzad, Muhammed Ikram; Shangaraev, Artem; Sharma, Ankita; Sharma, Mona; Sharma, Monika; 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; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Derradi De Souza, Rafael; Sozzi, Federica; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Stachel, Johanna; Stan, Ionel; Stankus, Paul; Stefanek, Grzegorz; 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; Suljic, Miljenko; Sultanov, Rishat; Sumbera, Michal; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Tabassam, Uzma; Takahashi, Jun; Tambave, Ganesh Jagannath; Tanaka, Naoto; Tangaro, Marco-Antonio; Tarhini, Mohamad; 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; Trombetta, Giuseppe; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vanat, Tomas; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vechernin, Vladimir; Veen, Annelies Marianne; Veldhoen, Misha; Velure, Arild; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara Limon, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Villatoro Tello, Abraham; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Vislavicius, Vytautas; Viyogi, Yogendra; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Vranic, Danilo; Vrlakova, Janka; Vulpescu, Bogdan; Wagner, Boris; Wagner, Jan; Wang, Hongkai; Wang, Mengliang; Watanabe, Daisuke; Watanabe, Yosuke; Weber, Michael; Weber, Steffen Georg; Weiser, Dennis Franz; Wessels, Johannes Peter; Westerhoff, Uwe; Whitehead, Andile Mothegi; Wiechula, Jens; Wikne, Jon; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yasin, Zafar; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-Kwon; Yoon, Jin Hee; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zardoshti, Nima; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Chunhui, Zhang; Zhang, Zuman; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2016-01-01

    The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity ($-0.5 10$ GeV/$c$), the particle ratios are consistent with those reported for pp and Pb-Pb collisions at the LHC energies. At intermediate $p_{\\rm T}$ the (anti)proton $R_{\\rm pPb}$ shows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification. At high $p_{\\rm T}$ the charged pion, kaon and (anti)proton $R_{\\rm pPb}$ are consistent with unity within statistical and systematic uncertainties.

  19. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  20. Rapidity distributions of antiprotons in Si+A and Au+A collisions

    Energy Technology Data Exchange (ETDEWEB)

    Shiva Kumar, B. [Yale Univ., New Haven, CT (United States); Beavis, D.; Bennett, M.; Carroll, J.B.; Chiba, J.; Crawford, H.J.; Debbe, R.; Doke, T.; Engelage, J.; Greiner, L.; Hayano, R.S.; Hallman, T.J.; Heckman, H.H.; Kashiwagi, T.; Kikuchi, J.; Kuo, C.; Lindstrom, P.J.; Mitchell, J.W.; Nagamiya, S.; Pope, K.; Stankus, P.; Tanaka, K.H.; Welsh, R.C.; Zhan, W.; E858/E878 Collaboration

    1994-01-03

    We have studied the production of {pi}{sup {+-}}, K{sup {+-}}, p, anti p, and light nuclei in relativistic Si+nucleus and Au+nucleus collisions using a zero degree focusing spectrometer. We find that for the antiprotons, the width of the rapidity distribution measured at p{sub t}=0 increases in going from Si+Al collisions to Au+Au collisions in spite of the lower center of mass energy of the latter measurement. We discuss our data, and the implications of our measurement. We also report sensitivity limits on the production of exotic particles. (orig.)

  1. Antiproton stopping at low energies: confirmation of velocity-proportional stopping power.

    Science.gov (United States)

    Møller, S P; Csete, A; Ichioka, T; Knudsen, H; Uggerhøj, U I; Andersen, H H

    2002-05-13

    The stopping power for antiprotons in various solid targets has been measured in the low-energy range of 1-100 keV. In agreement with most models, in particular free-electron gas models, the stopping power is found to be proportional to the projectile velocity below the stopping-power maximum. Although a stopping power proportional to velocity has also been observed for protons, the interpretation of such measurements is difficult due to the presence of charge exchange processes. Hence, the present measurements constitute the first unambiguous support for a velocity-proportional stopping power due to target excitations by a pointlike projectile.

  2. Time purified/separated antiproton beam at the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, M.; Barlett, M.L.; Bonner, B.; Borenstein, S.; Bridges, D.; Brown, H.; Buchanan, J.; Clement, J.C.; Daftari, I.; Debbe, R.

    1984-11-15

    A 1 km antiproton beam has been designed for construction at the AGS. The momentum band can be varied between +- 0.3% to +- 1.0%, and the resolution for tagged particles will be deltap/papprox.10/sup -4/ at beam rates as high as 10/sup 6/ p-bar/s. Separation by decay purification will be on the order of 1 p-bar/10(..pi../sup -/+..mu../sup -/). This beam will be used in a detailed investigation of Charmonium including a measurement of the chi widths. We will also search for expected but as yet unseen states, and search for possible I = 1 events which would imply the existence of four quark states. This facility will also lend itself to a wide variety of exciting physics such as the proton form factor including both e/sup +/e/sup -/ and ..gamma gamma.. final states, two-body hadron final states, antinucleus yields, and possibly tagged hadron beams (i.e., ..lambda.., ..gamma.., etc.). When heavy ions become available at the AGS, one can measure various long lived particle yields. Finally, with as many as 10/sup 7/ polarized muons in the beam, one has the possibility to use them for nuclear structure studies.

  3. Time purified/separated antiproton beam at the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, M.; Barlett, M.L.; Bonner, B.; Borenstein, S.; Bridges, D.; Brown, H.; Buchanan, J.; Clement, J.C.; Daftari, I.; Debbe, R.

    1984-01-01

    A 1 km antiproton beam has been designed for construction at the AGS. The momentum band can be varied between +-0.3% to +-1.0%, and the resolution for tagged particles will be deltap/p approx. 10/sup -4/ at beam rates as high as 10/sup 6/ anti p/s. Separation by decay purification will be on the order of 1 anti p/10(..pi../sup -/+..mu../sup -/). This beam will be used in a detailed investigation of Charmonium including a measurement of the chi widths. We will also search for expected but as yet unseen states, and search for possible I=1 events which would imply the existence of four quark states. This facility will also lend itself to a wide variety of exciting physics such as the proton form factor including both e/sup +/e/sup -/ and ..gamma gamma.. final states, two-body hadron final states, anti-nucleus yields, and possibly tagged hadron beams (i.e., Lambda, E, etc.). When heavy ions become available at the AGS, one can measure various long lived particle yields. Finally, with as many as 10/sup 7/ polarized muons in the beam, one has the possibility to use them for nuclear structure studies.

  4. Atomic Spectroscopy and Collisions Using Slow Antiprotons \\\\ ASACUSA Collaboration

    CERN Multimedia

    Matsuda, Y; Lodi-rizzini, E; Kuroda, N; Schettino, G; Hori, M; Pirkl, W; Mascagna, V; Malbrunot, C L S; Yamazaki, Y; Eades, J; Simon, M; Massiczek, O; Sauerzopf, C; Nagata, Y; Uggerhoj, U I; Mc cullough, R W; Toekesi, K M; Venturelli, L; Widmann, E; Zmeskal, J; Kanai, Y; Hayano, R; Knudsen, H; Kristiansen, H; Todoroki, K; Bartel, M A; Moller, S P; Charlton, M; Leali, M; Diermaier, M; Kolbinger, B

    2002-01-01

    ASACUSA (\\underline{A}tomic \\underline{S}pectroscopy \\underline{A}nd \\underline{C}ollisions \\underline{U}sing \\underline{S}low \\underline{A}ntiprotons) is a collaboration between a number of Japanese and European research institutions, with the goal of studying bound and continuum states of antiprotons with simple atoms.\\\\ Three phases of experimentation are planned for ASACUSA. In the first phase, we use the direct $\\overline{p}$ beam from AD at 5.3 MeV and concentrate on the laser and microwave spectroscopy of the metastable antiprotonic helium atom, $\\overline{p}$He$^+$, consisting of an electron and antiproton bound by the Coulomb force to the helium nucleus. Samples of these are readily created by bringing AD antiproton beam bunches to rest in helium gas. With the help of techniques developed at LEAR for resonating high precision laser beams with antiproton transitions in these atoms, ASACUSA achieved several of these first-phase objectives during a few short months of AD operation in 2000. Six atomic tr...

  5. The Floor's the Limit (Antiproton energies to hit new low)

    CERN Multimedia

    2000-01-01

    Celebrating the success of the RFQ in Aarhus. Left to right: Alessanda Lombardi (CERN), Iouri Bylinskii (CERN), Alex Csete (Aarhus), Ulrik Uggerhøj (Aarhus), Ryu Hayano (Tokyo, spokesman ASACUSA), Helge Knudsen (Aarhus), Werner Pirkl (CERN), Ryan Thompson (Aarhus), Søren P. Møller (Aarhus). Although in particle physics we are accustomed to strive for higher and higher energies, this is not always the most interesting thing to do with antiprotons. Indeed, as recent issues of the Bulletin have suggested, the signpost on the road to a closer look at the antiproton points towards ever-lower energies. The CERN Antiproton Decelerator decelerates antipro-tons emerging from a target placed in the path of a 26 GeV/c proton beam from 90 % of to about 10 % of the speed of light. However, even this is far too fast for many of the most interesting experiments on antiprotons planned by Danish and Japanese members of the ASACUSA collaboration. Tokyo University has therefore financed the con...

  6. Antiproton Flux in Cosmic Ray Propagation Models with Anisotropic Diffusion

    CERN Document Server

    Grajek, Phillip

    2010-01-01

    Recently a cosmic ray propagation model has been introduced, where anisotropic diffusion is used as a mechanism to allow for $\\mathcal{O}(100)$ km/s galactic winds. This model predicts a reduced antiproton background flux, suggesting an excess is being observed. We implement this model in GALPROP v50.1 and perform a $\\chi^2$ analysis for B/C, $^{10}$Be/$^{9}$Be, and the recent PAMELA $\\bar{p}/p$ datasets. By introducing a power-index parameter $\\alpha$ that dictates the dependence of the diffusion coefficient $D_{xx}$ on height $|z|$ away from the galactic plane, we confirm that isotropic diffusion models with $\\alpha=0$ cannot accommodate high velocity convective winds suggested by ROSAT, while models with $\\alpha=1$ ($D_{xx}\\propto |z|$) can give a very good fit. A fit to B/C and $^{10}$Be/$^{9}$Be data predicts a lower $\\bar{p}/p$ flux ratio than the PAMELA measurement at energies between approximately 2 GeV to 20 GeV. A combined fit including in addition the $\\bar{p}/p$ data is marginal, suggesting only a...

  7. Measurements of the top quark pair production cross section in lepton+jets final states using a topological multivariate technique as well as lifetime b-tagging in proton-antiproton collisions at {radical}(s)=1.96 TeV with the DOe detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Golling, T.

    2005-01-01

    Two alternative measurements of the tt production cross section at {radical}(s)=1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The tt production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X} = 5.13{sub -1.57}{sup +1.76} (stat) {sub -1.10}{sup +0.96} (syst) {+-}0.33 (lumi) pb in the muon+jets channel, using 229.1 pb{sup -1}, and in the combination with the electron+jets channel (226.3 pb{sup -1}) {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t}+X = 6.60{sub -1.28}{sup +1.37} (stat) {sub -1.11}{sup +1.25} (syst) {+-} 0.43 (lumi) pb. The second measurement presented reconstructs explicitly secondary vertices to do lifetime b-tagging. The measurement combines the muon+jets and the electron+jets channel, using 158.4 pb{sup -1} and 168.8 pb{sup -1}, respectively: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X} = 8.24{sub -1.25}{sup +1.34} (stat) {sub -1.63}{sup +1.89} (syst) {+-} 0.54 (lumi) pb. (orig.)

  8. The PANDA Experiment at FAIR - Subatomic Physics with Antiprotons

    CERN Document Server

    Messchendorp, Johan

    2016-01-01

    The non-perturbative nature of the strong interaction leads to spectacular phenomena, such as the formation of hadronic matter, color confinement, and the generation of the mass of visible matter. To get deeper insight into the underlying mechanisms remains one of the most challenging tasks within the field of subatomic physics. The antiProton ANnihilations at DArmstadt (PANDA) collaboration has the ambition to address key questions in this field by exploiting a cooled beam of antiprotons at the High Energy Storage Ring (HESR) at the future Facility for Antiproton and Ion Research (FAIR) combined with a state-of-the-art and versatile detector. This contribution will address some of the unique features of PANDA that give rise to a promising physics program together with state-of-the-art technological developments.

  9. Production of fragments and hyperfragments in antiproton-nucleus collisions

    Science.gov (United States)

    Feng, Zhao-Qing

    2016-04-01

    The formation mechanism of fragments with strangeness in collisions of antiprotons on nuclei has been investigated within the Lanzhou quantum molecular dynamics (LQMD) transport model. Production of strange particles in the antiproton-induced nuclear reactions is modeled within the LQMD model, in which all possible reaction channels such as elastic scattering, annihilation, charge exchange, and inelastic scattering in antibaryon-baryon, baryon-baryon, and meson-baryon collisions have been included. A coalescence approach is developed for constructing hyperfragments in phase space. The hyperfragments are formed within the narrower rapidities. It has the advantage of producing heavier hyperfragments and hypernuclides with strangeness s =-2 (double-Λ fragments) and s =1 (Λ ¯ fragments) in antiproton-induced reactions.

  10. Strangeness production and hypernucleus formation in antiproton induced reactions

    CERN Document Server

    Feng, Zhao-Qing

    2015-01-01

    Formation mechanism of fragments with strangeness in collisions of antiprotons on nuclei has been investigated within the Lanzhou quantum molecular dynamics (LQMD) transport approach combined with a statistical model (GEMINI) for describing the decays of excited fragments. Production of strange particles in the antiproton induced nuclear reactions is modeled within the LQMD model, in which all possible reaction channels such as elastic scattering, annihilation, charge exchange and inelastic scattering in antibaryon-baryon, baryon-baryon and meson-baryon collisions have been included. A coalescence approach is developed for constructing hyperfragments in phase space after de-excitation of nucleonic fragments. The combined approach could describe the production of fragments in low-energy antiproton induced reactions. Hyperfragments are formed within the narrower rapidities and lower kinetic energies. It has advantage to produce heavier hyperfragments and hypernuclides with strangeness s=-2 (double-$\\Lambda$ fra...

  11. Perspectives for low energy antiproton physics at FAIR

    CERN Document Server

    Widmann, Eberhard

    2014-01-01

    The CRYRING accelerator, previously located at the Manne Siegbahn Laboratory of Stockholm University, has been chosen by the FLAIR collaboration as the central accelerator for the planned facility. It has been modified to allow for high-energy injection and extraction and is capable of providing fast and slow extracted beams of antiprotons and highly charged ions. It is currently being installed at the ESR of GSI Darmstadt where it can be used with highly charged ions. The future possibilities for its use with slow antiprotons will be discussed.

  12. Calculated LET Spectrum from Antiproton Beams Stopping in Water

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    2009-01-01

    significantly differ from unity, which seems to warrant closer inspection of the radiobiology in this region. Monte Carlo simulations using FLUKA were performed for calculating the entire particle spectrum of a beam of 126 MeV antiprotons hitting a water phantom. In the plateau region of the simulated...... antiproton beam we observe a dose-averaged unrestricted LET of about 4 keV/μm, which is very different from the expected 0.6 keV/μm of an equivalent primary proton beam. Even though the fluence of secondaries is a magnitude less than the fluence of primary particles, the increased stopping power...

  13. AMS-02 antiprotons from annihilating or decaying dark matter

    Directory of Open Access Journals (Sweden)

    Koichi Hamaguchi

    2015-07-01

    Full Text Available Recently the AMS-02 experiment reported an excess of cosmic ray antiprotons over the expected astrophysical background. We interpret the excess as a signal from annihilating or decaying dark matter and find that the observed spectrum is well fitted by adding contributions from the annihilation or decay of dark matter with mass of O(TeV or larger. Interestingly, Wino dark matter with mass of around 3 TeV, whose thermal relic abundance is consistent with present dark matter abundance, can explain the antiproton excess. We also discuss the implications for the decaying gravitino dark matter with R-parity violation.

  14. High-precision comparison of the antiproton-to-proton charge-to-mass ratio

    Science.gov (United States)

    Ulmer, S.; Smorra, C.; Mooser, A.; Franke, K.; Nagahama, H.; Schneider, G.; Higuchi, T.; van Gorp, S.; Blaum, K.; Matsuda, Y.; Quint, W.; Walz, J.; Yamazaki, Y.

    2015-08-01

    Invariance under the charge, parity, time-reversal (CPT) transformation is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent. A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H-) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton to that for the proton and obtain . The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons as well as the respective figure of merit of the standard model extension by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of <720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of < 8.7 × 10-7.

  15. Loss of lung function after chemo-radiotherapy for NSCLC measured by perfusion SPECT/CT: Correlation with radiation dose and clinical morbidity

    DEFF Research Database (Denmark)

    Farr, Katherina P; Møller, Ditte S; Khalil, Azza A;

    2015-01-01

    BACKGROUND: The purpose of the study was to assess dose and time dependence of radiotherapy (RT)-induced changes in regional lung function measured with single photon emission computed tomography (SPECT) of the lung and relate these changes to the symptomatic endpoint of radiation pneumonitis (RP......) in patients treated for non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: NSCLC patients scheduled to receive curative RT of minimum 60 Gy were included prospectively in the study. Lung perfusion SPECT/CT was performed before and three months after RT. Reconstructed SPECT/CT data were registered...... to treatment planning CT. Dose to the lung was segmented into regions corresponding to 0-5, 6-20, 21-40, 41-60 and > 60 Gy. Changes (%) in regional lung perfusion before and after RT were correlated with regional dose and symptomatic RP (CTC grade 2-5) outcome. RESULTS: A total of 58 patients were included...

  16. Relative Biological Effectiveness and Peripheral Damage of Antiproton Annihilation

    CERN Multimedia

    Kavanagh, J N; Kaiser, F; Tegami, S; Schettino, G; Kovacevic, S; Hajdukovic, D; Welsch, C P; Currell, F J; Toelli, H T; Doser, M; Holzscheiter, M; Herrmann, R; Timson, D J; Alsner, J; Landua, R; Knudsen, H; Comor, J; Moller, S P; Beyer, G

    2002-01-01

    The use of ions to deliver radiation to a body for therapeutic purposes has the potential to be significant improvement over the use of low linear energy transfer (LET) radiation because of the improved energy deposition profile and the enhanced biological effects of ions relative to photons. Proton therapy centers exist and are being used to treat patients. In addition, the initial use of heavy ions such as carbon is promising to the point that new treatment facilities are planned. Just as with protons or heavy ions, antiprotons can be used to deliver radiation to the body in a controlled way; however antiprotons will exhibit additional energy deposition due to annihilation of the antiprotons within the body. The slowing down of antiprotons in matter is similar to that of protons except at the very end of the range beyond the Bragg peak. Gray and Kalogeropoulos estimated the additional energy deposited by heavy nuclear fragments within a few millimeters of the annihilation vertex to be approximately 30 MeV (...

  17. Outer casing of the AA antiproton production target

    CERN Multimedia

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long (actually a row of 11 rods, each 1 cm long) and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing made of stainless steel. The casing had fins for forced-air cooling.

  18. Enhancing trappable antiproton populations through deceleration and frictional cooling

    Energy Technology Data Exchange (ETDEWEB)

    Zolotorev, Max; Sessler, Andrew; Penn, Gregory; Wurtele, Jonathan S.; Charman, Andrew E.

    2012-03-20

    CERN currently delivers antiprotons for trapping experiments with the Antiproton Decelerator (AD), which slows the antiprotons down to about 5 MeV.This energy is currently too high for direct trapping, and thick foils are used to slow down the beam to energies which can be trapped.To allow further deceleration to $\\sim 100 \\;\\mbox{keV}$, CERN is initiating the construction of ELENA,consisting of a ring which will combine RF deceleration and electron cooling capabilities. We describe a simple frictionalcooling scheme that can serve to provide significantly improved trapping efficiency, either directly from the AD or first usinga standard deceleration mechanism (induction linac or RFQ). This scheme could be implemented in a short time.The device itself is short in length, uses accessible voltages, and at reasonable cost could serve in the interim beforeELENA becomes operational, or possibly in lieu of ELENA for some experiments. Simple theory and simulations provide a preliminary assessment of theconcept and its strengths and limitations, and highlight important areas for experimental studies, in particular to pin down the level of multiplescattering for low-energy antiprotons. We show that the frictional cooling scheme can provide a similar energy spectrum to that of ELENA,but with higher transverse emittances.

  19. What Does The PAMELA Antiproton Spectrum Tell Us About Dark Matter?

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, Dan [Chicago U., Astron. Astrophys. Ctr.; Linden, Tim [Chicago U., KICP; Mertsch, Philipp [KIPAC, Menlo Park

    2015-03-11

    Measurements of the cosmic ray antiproton spectrum can be used to search for contributions from annihilating dark matter and to constrain the dark matter annihilation cross section. Depending on the assumptions made regarding cosmic ray propagation in the Galaxy, such constraints can be quite stringent. We revisit this topic, utilizing a set of propagation models fit to the cosmic ray boron, carbon, oxygen and beryllium data. We derive upper limits on the dark matter annihilation cross section and find that when the cosmic ray propagation parameters are treated as nuisance parameters (as we argue is appropriate), the resulting limits are significantly less stringent than have been previously reported. We also note (as have several previous groups) that simple GALPROP-like diffusion-reacceleration models predict a spectrum of cosmic ray antiprotons that is in good agreement with PAMELA's observations above ~ 5 GeV, but that significantly underpredict the flux at lower energies. Although the complexity of modeling cosmic ray propagation at GeV-scale energies makes it difficult to determine the origin of this discrepancy, we consider the possibility that the excess antiprotons are the result of annihilating dark matter. Suggestively, we find that this excess is best fit for mDM ~ 35 GeV and σ v ~ 10$-$26 cm3/s (to $b\\bar{_b}$), in good agreement with the mass and cross section previously shown to be required to generate the gamma-ray excess observed from the Galactic Center.

  20. Thermal excitation of heavy nuclei with 5-15 GeV/c antiproton, proton and pion beams

    CERN Document Server

    Beaulieu, L; Hsi, W C; Lefort, T; Pienkowski, L; Korteling, R G; Wang, G; Back, B B; Bracken, D S; Breuer, H; Cornell, E A; Gimeno-Nogues, F; Ginger, D S; Gushue, S; Huang, M J; Laforest, R; Lynch, W G; Martin, E; Morley, K B; Ramakrishnan, E; Remsberg, L P; Rowland, D; Ruangma, A; Tsang, M B; Viola, V E; Winchester, E M; Xi, H; Yennello, S J

    1999-01-01

    Excitation-energy distributions have been derived from measurements of 5.0-14.6 GeV/c antiproton, proton and pion reactions with $^{197}$Au target nuclei, using the ISiS 4$\\pi$ detector array. The maximum probability for producing high excitation-energy events is found for the antiproton beam relative to other hadrons, $^3$He and $\\bar{p}$ beams from LEAR. For protons and pions, the excitation-energy distributions are nearly independent of hadron type and beam momentum above about 8 GeV/c. The excitation energy enhancement for $\\bar{p}$ beams and the saturation effect are qualitatively consistent with intranuclear cascade code predictions. For all systems studied, maximum cluster sizes are observed for residues with E*/A $\\sim$ 6 MeV.

  1. Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium.

    Science.gov (United States)

    Massiczek, O; Friedreich, S; Juhász, B; Widmann, E; Zmeskal, J

    2011-12-11

    The design and properties of a new cryogenic set-up for laser-microwave-laser hyperfine structure spectroscopy of antiprotonic helium - an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland - are described. Similar experiments for (4)He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised (3)He gas volume and different dimensions of the microwave resonator for measuring the (3)He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD.

  2. Liquid helium-free cryostat and hermetically sealed cryogenic microwave cavity for hyperfine spectroscopy of antiprotonic helium

    Energy Technology Data Exchange (ETDEWEB)

    Massiczek, O., E-mail: oswald.massiczek@cern.ch [Stefan Meyer Institute for Subatomic Physics, Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna (Austria); Friedreich, S.; Juhasz, B.; Widmann, E.; Zmeskal, J. [Stefan Meyer Institute for Subatomic Physics, Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna (Austria)

    2011-12-11

    The design and properties of a new cryogenic set-up for laser-microwave-laser hyperfine structure spectroscopy of antiprotonic helium - an experiment performed at the CERN-Antiproton Decelerator (AD), Geneva, Switzerland - are described. Similar experiments for {sup 4}He have been performed at the AD for several years. Due to the usage of a liquid helium operated cryostat and therefore necessary refilling of coolants, a loss of up to 10% beamtime occurred. The decision was made to change the cooling system to a closed-circuit cryocooler. New hermetically sealed target cells with minimised {sup 3}He gas volume and different dimensions of the microwave resonator for measuring the {sup 3}He transitions were needed. A new set-up has been designed and tested at Stefan Meyer Institute in Vienna before being used for the 2009 and 2010 beamtimes at the AD.

  3. Radiotherapy for Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena [Rigshospitalet Copenhagen Univ. (Denmark). Depts. of Oncology and Haematology; Yahalom, Joachim (eds.) [Memorial Sloan-Kettering Cancer, New York, NY (United States). Dept. of Radiation Oncology

    2011-07-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  4. Search for Resonances in the Photoproduction of Proton-Antiproton Pairs

    Energy Technology Data Exchange (ETDEWEB)

    Stokes, Burnham [Florida State Univ., Tallahassee, FL (United States)

    2006-01-01

    Results are reported on the reaction γp → p$\\bar{p}$p with beam energy in the range 4.8-5.5 GeV. The data were collected at the Thomas Jefferson National Accelerator Facility in CLAS experiment E01-017(G6C). The focus of this study is an understanding of the mechanisms of photoproduction of proton-antiproton pairs, and to search for intermediate resonances, both narrow and broad, which decay to p$\\bar{p}$. The total measured cross section in the photon energy range 4.8-5.5 GeV is σ = 33 ± 2 nb. Measurement of the cross section as a function of energy is provided. An upper limit on the production of a narrow resonance state previously observed with a mass of 2.02 GeV/c2 is placed at 0.35 nb. No intermediate resonance states were observed. Meson exchange production appears to dominate the production of the proton-antiproton pairs.

  5. Meas.of the Ratio Between Double and Single Ionization of Helium for Antiprotons

    CERN Multimedia

    2002-01-01

    The aim of this experiment is to measure the ratio between double and single ionization of helium by antiprotons in the energy range $>$~3~MeV. Comparison with already existing proton data will yield information on the mechanisms for double ionization, which could not be extracted from previous comparisons between ratios measured for equivelocity electrons and protons. The most basic information to be obtained from an antiproton experiment will be the amount of correlation existing between the two electrons in the ground-state helium atom.\\\\ \\\\ The equipment consists of a gas cell, which employs slow-ion collection via the so-called condenser-plate method for the absolute sum of partial-ionization cross sections and determination of the relative contribution of multiple charged ions by TOF. The gas cell has movable entrance and exit slits and a grid system to account for secondary emission from the collection of slow ions. Together with a field of 800~V/cm in the collision region, the potentials of the TOF sp...

  6. High precision spectroscopy of pionic and antiprotonic atoms; Spectroscopie de precision des atomes pioniques et antiprotoniques

    Energy Technology Data Exchange (ETDEWEB)

    El-Khoury, P

    1998-04-15

    The study of exotic atoms, in which an orbiting electron of a normal atom is replaced by a negatively charged particle ({pi}{sup -}, {mu}{sup -}, p, {kappa}{sup -}, {sigma}{sup -},...) may provide information on the orbiting particle and the atomic nucleus, as well as on their interaction. In this work, we were interested in pionic atoms ({pi}{sup -14} N) on the one hand in order to determine the pion mass with high accuracy (4 ppm), and on the other hand in antiprotonic atoms (pp-bar) in order to study the strong nucleon-antinucleon interaction at threshold. In this respect, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high stop density for particles in gas targets at low pressure. Using curved crystals, an extended X-ray source could be imaged onto the detector. Charge-Coupled Devices were used as position sensitive detectors in order to measure the Bragg angle of the transition to a high precision. The use of gas targets resolved the ambiguity owing to the number of K electrons for the value of the pion mass, and, for the first time, strong interaction shift and broadening of the 2p level in antiprotonic hydrogen were measured directly. (author)

  7. A Measurement of the production cross section of top-antitop pairs in proton-antiproton collisions at a center of mass of 1.96 TeV using secondary vertex b-tagging.

    Energy Technology Data Exchange (ETDEWEB)

    Bachacou, Henri

    2004-12-01

    A measurement of the t{bar t} pair production cross section is presented using 162 pb{sup -1} of data collected by the CDF experiment during Run II at the Tevatron. t{bar t} events in the lepton+jets channel are isolated by identifying electrons and muons, reconstructing jets and transverse missing energy, and identifying b jets with a secondary vertex tagging algorithm. The efficiency of the algorithm is measured in a control sample using a novel technique that is less dependent on the simulation. For a top quark mass of 175 GeV/c{sup 2}, a cross section of {sigma}{sub t{bar t}} = 5.6{sub -1.1}{sup +1.2}(stat.){sub -0.6}{sup +0.9}(syst.)pb is measured.

  8. First Measurement of the Production of a W Boson in Association with a Single Charm Quark in Proton Anti-proton Collisions at $\\sqrt{s}$=1.96 TeV

    CERN Document Server

    Aaltonen, T; Akimoto, T; Albrow, M G; Alvarez-Gonzalez, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P H; Bedeschi, F; Bednar, P; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bölla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, Yu A; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrerar, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carrillol, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerritop, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenarr, C; Cuevaso, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; De Barbaro, P; De Cecco, S; Deisher, A; De Lentdeckerd, G; De Lorenzo, G; Dell'Orso, Mauro; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernández, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; García, J E; Garfinkel, A F; Genser, K; Gerberich, H; Gerdes, D; Giagu, S; Giakoumopoloua, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokarisa, N; Giordani, M; Giromini, P; Giunta, M; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gómez, G; Gómez-Ceballos, G; Goncharov, M; Gonzlez, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraesda Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hillc, C S; Hirschbuehl, D; Höcker, A; Hou, S; Houlden, M; Hsu, S C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Koay, S A; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Le Compte, T; Lee, J; Lee, J; Lee, Y J; Leeq, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Linacre, J; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lu, R S; Lucchesi, D; Lueck, J; Luci, C; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Mäki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manganos, M L; Manousakisa, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, M; Martinj, V; Martínez, M; Martinez-Ballarin, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNultyi, R; Mehta, A; Mehtälä, P; Menzemerk, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M; Movilla-Fernández, P A; Mülmenstädt, J; Mukherjee, A; Müller, T; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsenf, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Österberg, K; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, Aldo L; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohosh, F; Punzi, G; Pursley, J; Rademackerc, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P B; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Salt, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyria, A; Shalhout, S Z; Shapiro, M D; Shears, T G; Shepard, P F; Sherman, D; Shimojiman, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakian, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Söderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Saint-Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffarde, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thomg, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; Van Remortel, N; Varganov, A; Vataga, E; Vazquezl, F; Velev, G; Vellidisa, C; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouevq, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner-Kuhr, J; Wagner, W; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whitesone, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittichg, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yangm, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhengb, Y; Zucchelli, S

    2007-01-01

    We present the first measurement of the production cross section of a W boson with a single charm quark (c) in p-pbar collisions at $\\sqrt{s}$=1.96 TeV, using soft muon tagging of c jets. In a data sample of ~1.8 fb-1, recorded with the CDF II detector at the Fermilab Tevatron, we select events with W+1 or 2 jets. We use the charge correlation between the W and the muon from the semileptonic decay of a charm hadron to extract the Wc signal. We measure sigma_{Wc}(p_{Tc}>20 GeV/c, |\\eta_c|\\ell\

  9. A measurement of the t anti t production cross section in proton-antiproton collisions at {radical}s=1.96 TeV with the DOe detector at the Tevatron using final states with a muon and jets

    Energy Technology Data Exchange (ETDEWEB)

    Klute, M.

    2004-02-01

    A preliminary measurement of the t anti t production cross section at {radical}s=1.96 TeV is presented. The {mu}-plus-jets final state is analyzed in a data sample of 94 pb{sup -1} and a total of 14 events are selected with a background expectation of 11.7{+-}1.9 events. The measurement yields: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X}=2.4{sub -3.5}{sup +4.2}(stat.){sub -2.6}{sup +2.5}(syst.){+-}0.3(lumi.) pb. The analysis, being part of a larger effort to re-observe the top quark in Tevatron Run II data and to measure the production cross section, is combined with results from the available analysis channels. The combined result yields: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X}=8.1{sub -2.0}{sup +2.2}(stat.){sub -1.4}{sup +1.6}(syst.){+-}0.8(lumi.) pb.

  10. A Measurement of the Inclusive Z / γ* → μ+ μ- Cross-Section and Study of W and Z Events in proton - anti-proton Collisions at D0

    Energy Technology Data Exchange (ETDEWEB)

    Nurse, Emily L. [Univ. of Manchester (United Kingdom)

    2005-01-01

    A measurement of the inclusive Z/γ* → μ+ μ- cross section for Mμμ > 40 GeV at √s = 1.96 TeV is presented. The measurement is performed using a data sample corresponding to an integrated luminosity of 147.7 pb-1, collected with the D0 detector at the Tevatron, Fermilab, between September 2002 and October 2003. A total of 14352 di-muon events are selected and a final result of σ(Z/γ*) = 327.8 ± 3.4(stat.) ± 8.4(syst.) ± 21.3(lumi.) pb is obtained. Correcting the number of di-muon events by a factor of 0.885 ± 0.015 for the contribution from pure γ* exchange and Z/γ* interference, the inclusive Z → μ+ μ- cross section is found to be: σ(Z) = 290.1 ± 3.0(stat.) ± 7.4(syst.) ± 18.9(lumi.) pb. Finally, comparisons of W and Z boson pT distributions as measured with D0 during Run I of the Tevatron are compared to HERWIG and MC@NLO predictions. Relevant parameters in the simulations are tuned to obtain the best possible fit to the data. An excellent agreement is found for both HERWIG and MC@NLO.

  11. Procedure to measure the neutrons spectrum around a lineal accelerator for radiotherapy; Procedimiento para medir el espectro de los neutrones en torno a un acelerador lineal para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Benites R, J. L. [Servicios de Salud de Nayarit, Centro Estatal de Cancerologia, Calzada de la Cruz 116 Sur, 63000 Tepic, Nayarit (Mexico); Salas L, M. A., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Agronomia, Apdo. Postal 336, 98000 Zacatecas (Mexico)

    2013-10-15

    An experimental procedure was developed, by means of Bonner spheres, to measure the neutrons spectrum around Linacs of medical use that only requires of a single shot of the accelerator; to this procedure we denominate Planetary or Isocentric method. One of the problems associated to the neutrons spectrum measurement in a radiotherapy room with lineal accelerator is because inside the room a mixed, intense and pulsed radiation field takes place affecting the detection systems based on active detector; this situation is solved using a passive detector. In the case of the Bonner spheres spectrometer the active detector has been substituted by activation detectors, trace detectors or thermoluminescent dosimeters. This spectrometer uses several spheres that are situated one at a time in the measurement point, this way to have the complete measurements group the accelerator should be operated, under the same conditions, so many times like spheres have the spectrometer, this activity can consume a long time and in occasions due to the work load of Linac to complicate the measurement process too. The procedure developed in this work consisted on to situate all the spectrometer spheres at the same time and to make the reading by means of a single shot, to be able to apply this procedure, is necessary that before the measurements two characteristics are evaluated: the cross-talking of the spheres and the symmetry conditions of the neutron field. This method has been applied to determine the photo-neutrons spectrum produced by a lineal accelerator of medical use Varian ix of 15 MV to 100 cm of the isocenter located to 5 cm of depth of a solid water mannequin of 30 x 30 x 15 cm. The spectrum was used to determine the total flow and the environmental dose equivalent. (Author)

  12. Laser spectroscopy of the antiprotonic helium atom – its energy levels and state lifetimes

    CERN Document Server

    Hidetoshi, Yamaguchi

    2003-01-01

    The antiprotonic atom is a three-body exotic system consisting of an antiproton, an electron and a helium nucleus. Its surprising longevity was found and has been studied for more than 10 years. In this work, transition energies and lifetimes of this exotic atom were systematically studied by using the antiproton beam of AD(Antiproton Decelerator) facility at CERN, with an RFQ antiproton decelerator, a narrow-bandwidth laser, Cerenkov counters with fast-response photomultiplier tubes, and cryogenic helium target systems. Thirteen transition energies were determined with precisions of better than 200 ppb by a laser spectroscopy method, together with the elimination of the shift effect caused by collisions with surrounding atoms. Fifteen lifetimes (decay rates) of short-lived states were determined from the time distributions of the antiproton-annihilation signals and the resonance widths of the atomic spectral lines. The relation between the magnitude of the decay rates and the transition multipolarity was inv...

  13. Monte-Carlo simulation of events for (un)polarized Drell-Yan with antiprotons

    CERN Document Server

    Bianconi, A

    2004-01-01

    The complete knowledge of the nucleon spin structure at leading twist requires also addressing the transverse spin distribution of quarks, or transversity, which is yet unexplored because of its chiral-odd nature. Transversity can be best extracted from single-spin asymmetries in fully polarized Drell-Yan processes with antiprotons, where valence contributions are involved anyway. Alternatively, in single-polarized Drell-Yan the transversity happens convoluted with another chiral-odd function, which is likely to be responsible for the well known (and yet unexplained) violation of the Lam-Tung sum rule in the corresponding unpolarized cross section. We present Monte-Carlo simulations for the unpolarized and single-polarized Drell-Yan $\\bar{p} p^{(\\uparrow)} \\to \\mu^+ \\mu^- X$ with antiproton beam energies of 40 and 15 GeV as a test case, in order to estimate the minimum number of events needed to extract the above chiral-odd distributions from future measurements at the HESR ring at GSI. It is important to stu...

  14. X-rays from antiprotonic sup 3 He and sup 4 He

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.; Bacher, R.; Bluem, P.; Gotta, D.; Heitlinger, K.; Kunold, W.; Rohmann, D. (Kernforschungszentrum Karlsruhe GmbH (Germany, F.R.). Inst. fuer Kernphysik Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Experimentelle Kernphysik); Egger, J.; Simons, L.M. (Paul Scherrer Inst. (PSI), Villigen (Switzerland)); Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland))

    1991-02-01

    Antiprotonic X-rays from the helium isotopes have been observed at pressures of 36, 72, 375 and 600 mbar. The antiproton beam from LEAR with momenta of 309 and 202 MeV/c has been stopped at these pressures using the cyclotron trap. The X-rays were detected with Si(Li) and intrinsic Ge semiconductor detectors. Absolute X-ray yields were determined and the strong-interaction 2p shifts and the 2p and 3d broadenings measured to be {epsilon}{sub 2p}=(-17{plus minus}4) eV, {Gamma}{sub 2p}=(25{plus minus}9) eV and {Gamma}{sub 3d}=(2.14{plus minus}0.18) meV for anti p{sup 3}He and {epsilon}{sub 2p}=(-18{plus minus}2) eV, {Gamma}{sub 2p}=(45{plus minus}5) eV and {Gamma}{sub 3d}=(2.36{plus minus}0.10) meV for anti p{sup 4}He. (orig.).

  15. GAPS - Dark matter search with low-energy cosmic-ray antideuterons and antiprotons

    CERN Document Server

    von Doetinchem, P; Boggs, S; Fuke, H; Hailey, C J; Mognet, S I; Ong, R A; Perez, K; Zweerink, J

    2015-01-01

    The GAPS experiment is foreseen to carry out a dark matter search by measuring low-energy cosmic-ray antideuterons and antiprotons with a novel detection approach. It will provide a new avenue to access a wide range of different dark matter models and masses from about 10GeV to 1TeV. The theoretically predicted antideuteron flux resulting from secondary interactions of primary cosmic rays is very low. Well-motivated theories beyond the Standard Model contain viable dark matter candidates, which could lead to a significant enhancement of the antideuteron flux due to annihilation or decay of dark matter particles. This flux contribution is believed to be especially large at low energies, which leads to a high discovery potential for GAPS. The GAPS low-energy antiproton search will provide some of the most stringent constraints on ~30GeV dark matter, will provide the best limits on primordial black hole evaporation on galactic length scales, and explore new discovery space in cosmic-ray physics. GAPS is designed...

  16. A possible dark matter annihilation signal in the AMS-02 antiproton data

    CERN Document Server

    Cui, Ming-Yang; Tsai, Yue-Lin Sming; Fan, Yi-Zhong

    2016-01-01

    A new approach has been adopted to probe the dark matter signal using the latest AMS-02 cosmic ray antiproton flux data. Different from previous studies, we do not assume specific propagation, injection, and solar modulation parameters when calculating the antiproton fluxes, but use the results inferred from the B/C ratio and proton data from the recent PAMELA/AMS-02 measurements instead. A joint likelihood method including the likelihood of these background parameters is established within the Bayesian framework. We find that a dark matter signal is favored with a high test statistic value of $\\sim 70$. The rest mass of the dark matter particles is $\\sim 30-70$ GeV and the velocity-averaged hadronic annihilation cross section is about $(1-6)\\times 10^{-26}$ cm$^{3}$s$^{-1}$, in agreement with that needed to account for the Galactic center GeV excess and/or the weak GeV emission from dwarf galaxies Reticulum 2 and Tucana III. Tight constraints on the dark matter annihilation models are also set in a wide mass...

  17. Novel dark matter constraints from antiprotons in the light of AMS-02

    CERN Document Server

    Cuoco, Alessandro; Korsmeier, Michael

    2016-01-01

    We evaluate dark matter (DM) limits from cosmic-ray antiproton observations using the recent precise AMS-02 measurements. We properly take into account cosmic-ray propagation uncertainties fitting at the same time DM and propagation parameters, and marginalizing over the latter. We find a significant (~4.5 sigma) indication of a DM signal for DM masses near 80 GeV, with a hadronic annihilation cross-section close to the thermal value, sigma v ~3e-26 cm3s-1. Intriguingly, this signal is compatible with the DM interpretation of the Galactic center gamma-ray excess. Confirmation of the signal will require a more accurate study of the systematic uncertainties, i.e., the antiproton production cross-section, and modelling of the solar modulation effect. Interpreting the AMS-02 data in terms of upper limits on hadronic DM annihilation, we obtain strong constraints excluding a thermal annihilation cross-section for DM masses below about 50 GeV and in the range between approximately 150 and 500 GeV, even for conservat...

  18. Cryogenic Current Comparator as Low Intensity Beam Current Monitor in the CERN Antiproton Decelerators

    CERN Document Server

    Fernandes, M; Soby, L; Welsch, CP

    2013-01-01

    In the low-energy Antiproton Decelerator (AD) and the future Extra Low ENergy Antiproton (ELENA) rings at CERN, an absolute measurement of the beam intensity is essential to monitor any losses during the deceleration and cooling phases. However, existing DC current transformers can hardly reach the μA level, while at the AD and ELENA currents can be as low as 100 nA. A Cryogenic Current Comparator (CCC) based on a superconducting quantum interference device (SQUID) is currently being designed and shall be installed in the AD and ELENA machines. It should meet the following specifications: A current resolution smaller than 10 nA, a dynamic range covering currents between 100 nA and 1 mA, as well as a bandwidth from DC to 1 kHz. Different design options are being considered, including the use of low or high temperature superconductor materials, different CCC shapes and dimensions, different SQUID characteristics, as well as electromagnetic shielding requirements. In this contribution we present first results f...

  19. Measurement of the neutral B meson decay mixing frequency using a new probability based self-tagging algorithm applied to inclusive lepton events from proton-antiproton collisions at center-of-mass energy = 1.8 TeV

    Science.gov (United States)

    Shah, Tushar

    We present a measurement of the Bd mixing frequency performed in an inclusive lepton sample, B --> l + X. A secondary vertex identifies a B meson decay, and a high pt lepton determines the flavor at the time of decay. We use a self-tagging algorithm (exploiting the correlation between the charge of particles produced along with a B meson and its flavor) in order to determine the B flavor at the time of production. Confusion of B daughter particles with charge-flavor correlated particles can cause significant degradation of the flavor tagging performance. Monte Carlo based probability distributions over kinematic and geometric properties of tracks are used to distinguish between potential self-tagging candidates and unidentified B meson daughters. We measure Δmd = 0.42 +/- 0.09(stat) +/- 0.03(sys) × (ps) -1. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  20. Measurement of the Single Top Quark Cross Section in the Lepton Plus Jets Final State in Proton-Antiproton Collisions at a Center of Mass Energy of 1.96 TeV Using the CDF II Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhenbin [Baylor Univ., Waco, TX (United States)

    2012-01-01

    We present a measurement of the single top quark cross section in the lepton plus jets final state using an integrated luminosity corresponding to 7.5 fb-1 of p\\bar p collision data collected by the Collider Detector at Fermilab. The single top candidate events are identified by the signature of a charged lepton, large missing transverse energy, and two or three jets with at least one of them identified as originating from a bottom quark. A new Monte Carlo generator POWHEG is used to model the single top quark production processes, which include s-channel, t-channel, and Wt-channel. A neural network multivariate method is exploited to discriminate the single top quark signal from the comparatively large backgrounds. We measure a single top production cross section of $3.04^{+0.57}_{-0.53} (\\mathrm{stat.~+~syst.})$ pb assuming $m_{\\rm top}=172.5$~GeV/$c^2$. In addition, we extract the CKM matrix element value $|V_{tb}|=0.96\\pm 0.09~(\\mathrm{stat.~+~syst.})\\ ± 0.05~(\\mathrm{theory})$ and set a lower limit of $|V_{tb}|>0.78$ at the 95% credibility level.

  1. Dark matter for excess of AMS-02 positrons and antiprotons

    Directory of Open Access Journals (Sweden)

    Chuan-Hung Chen

    2015-07-01

    Full Text Available We propose a dark matter explanation to simultaneously account for the excess of antiproton-to-proton and positron power spectra observed in the AMS-02 experiment while having the right dark matter relic abundance and satisfying the current direct search bounds. We extend the Higgs triplet model with a hidden gauge symmetry of SU(2X that is broken to Z3 by a quadruplet scalar field, rendering the associated gauge bosons stable weakly-interacting massive particle dark matter candidates. By coupling the complex Higgs triplet and the SU(2X quadruplet, the dark matter candidates can annihilate into triplet Higgs bosons each of which in turn decays into lepton or gauge boson final states. Such a mechanism gives rise to correct excess of positrons and antiprotons with an appropriate choice of the triplet vacuum expectation value. Besides, the model provides a link between neutrino mass and dark matter phenomenology.

  2. A Good Statistics Study of Antiproton Interactions with Nuclei

    CERN Multimedia

    2002-01-01

    This experiment extends the study of inclusive pion production and the correlation between pions which result from hadron-nucleus collisions at intermediate and high energies to the antiproton-nucleus system. It is part of a long term systematic search for exotic nuclear phenomena. The correlation data will be used to extract, via pion interferometry, the size and coherence of the annihilation source in nuclei. In addition, the reaction @* + A @A p + A* will be studied to look for structure in the proton spectra which antiproton-nucleus bound states.\\\\ \\\\ The experimental system is based on a flexible, broad range, large acceptance (1~steradian) spectrometer which consists of an 80~cm diameter dipole magnet surrounded with detector arrays. These detectors provide momentum, energy loss, Cerenkov and time of flight information for up to ten ejectiles per event. Momentum resolution varies from 1\\% to 3\\%, depending on energy.

  3. The CERN Antiproton Collider Programme Accelerators and Accumulation Rings

    CERN Document Server

    Koziol, Heribert

    2004-01-01

    One of CERN's most daring and successful undertakings was the quest for the intermediate bosons, W and Z. In this paper, we describe the accelerator part of the venture which relied on a number of innovations: an extension of the budding method of stochastic cooling by many orders of magnitude; the construction of the Antiproton Accumulator, depending on several novel accelerator methods and technologies; major modifications to the 26 GeV PS Complex; and the radical conversion of the 300 GeV SPS, which just had started up as an accelerator, to a protonâ€"antiproton collider. The SPS Collider had to master the beamâ€"beam effect far beyond limits reached ever before and had to function in a tight symbiosis with the huge detectors UA1 and UA2.

  4. Observation of pion - bottom meson charge-flavor correlations and measurement of time-dependent neutral bottom meson - anti-neutral bottom meson mixing in proton - anti-proton collisions

    Science.gov (United States)

    Maksimovic, Petar

    1998-12-01

    We present a study of time-dependent B0-/bar B0 mixing in pp collisions at 1.8 TeV using 110 pb-1 collected with the CDF detector at the Fermilab Tevatron Collider. B mesons are partially reconstructed using the semileptonic decays B0/tol+D(*)-X and B+/to l+/overline[D0]X (and their charge conjugates). B meson-charged pion correlations are used in order to determine the flavor of the B meson at t = 0. Such correlations are expected to arise from pions produced in the fragmentation chain and also from B** decays. We measure the efficiency and purity of this flavor tagging method for both charged and neutral B mesons. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  5. Measurement of the top-antitop quark pair differential cross section with respect to the invariant mass of the pair in proton-antiproton collisions at a center of mass energy of 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Bridgeman, Alice Patricia [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2008-01-01

    I present a measurement of the t$\\bar{t}$ differential cross section, dσ/dMt$\\bar{t}$, in p$\\bar{p}$ collisions at √s = 1.96 TeV using 2.7 fb-1 of CDF II data. I find that dσ/dMt$\\bar{t}$ is consistent with the Standard Model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions. I set limits on the ratio Κ/MPl in the Randall-Sundrum model by looking for Kaluza Klein gravitons which decay to top quarks. I find Κ/MPl > 0.16 at the 95% confidence level.

  6. Measurements of top quark pair production cross section in proton anti-proton collisions at √s = 1.96 TeV in the τ + jets final state using 1 fb-1 of data

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, Sohrab [Univ. of Oklahoma, Norman, OK (United States)

    2009-01-01

    This dissertation presents a new measurement of p$\\bar{p}$ → t$\\bar{t}$X production at √s = 1.96 TeV using 974.2 pb-1of data collected with the D0 detector between 2002 and 2006. We focus on the final state where the W boson from one of the top quarks decays into a τ lepton and its associated neutrino, while the other W boson decays into a quark-antiquark pair. We aim to select those events in which the τ lepton subsequently decays hadronically, meaning to one or three charged hadrons, zero or more neutral hadrons and a tau neutrino (the charge conjugate processes are implied in all of the above). The observable signature thus consists of a narrow calorimeter shower with associated track(s) characteristic of a hadronic tau decay, four or more jets, of which two are initiated by b quarks accompanying the W's in the top quark decays, and a large net missing momentum in the transverse plane due to the energetic neutrino-antineutrino pair that leave no trace in the detector media. The preliminary result for the measured cross section is: σ(t$\\bar{t}$) = 6.9-1.2 +1.2(stat)-0.7+0.8(syst) ± 0.4 (lumi) pb. This indicates that our finding is consistent with the Standard Model prediction.

  7. Selected Papers on Low-Energy Antiprotons and Possible Applications

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Robert [Fermilab

    1998-09-19

    The only realistic means by which to create a facility at Fermilab to produce large amounts of low energy antiprotons is to use resources which already exist. There is simply too little money and manpower at this point in time to generate new accelerators on a time scale before the turn of the century. Therefore, innovation is required to modify existing equipment to provide the services required by experimenters.

  8. The Production and Study of Cold Antiprotons and Antihydrogen

    Science.gov (United States)

    2015-08-03

    baryon system . A second goal is to compare the antiproton and proton charge-to-mass ratios to higher precision. All interesting comparisons of the...trap designs now being used in devices that analyze pharmaceuticals and chemical compounds. There are hundreds of scientific citations to the reports... theories (QFT) for which there is a CPT theorem if plausible assump- tions (like causality, locality and Lorentz invariance) are made. Of course

  9. Measurement of the top quark pair production cross section in proton-antiproton collisions at a center of mass energy of 1.96 TeV, hadronic top decays with the D0 detector

    Energy Technology Data Exchange (ETDEWEB)

    Hegeman, Jeroen Guido [Univ. of Twente, Enschede (Netherlands)

    2009-01-16

    Of the six quarks in the standard model the top quark is by far the heaviest: 35 times more massive than its partner the bottom quark and more than 130 times heavier than the average of the other five quarks. Its correspondingly small decay width means it tends to decay before forming a bound state. Of all quarks, therefore, the top is the least affected by quark confinement, behaving almost as a free quark. Its large mass also makes the top quark a key player in the realm of the postulated Higgs boson, whose coupling strengths to particles are proportional to their masses. Precision measurements of particle masses for e.g. the top quark and the W boson can hereby provide indirect constraints on the Higgs boson mass. Since in the standard model top quarks couple almost exclusively to bottom quarks (t → Wb), top quark decays provide a window on the standard model through the direct measurement of the Cabibbo-Kobayashi-Maskawa quark mixing matrix element Vtb. In the same way any lack of top quark decays into W bosons could imply the existence of decay channels beyond the standard model, for example charged Higgs bosons as expected in two-doublet Higgs models: t → H+b. Within the standard model top quark decays can be classified by the (lepton or quark) W boson decay products. Depending on the decay of each of the W bosons, t$\\bar{t}$ pair decays can involve either no leptons at all, or one or two isolated leptons from direct W → e$\\bar{v}${sub e} and W → μ$\\bar{v}$μ decays. Cascade decays like b → Wc → e$\\bar{v}$ec can lead to additional non-isolated leptons. The fully hadronic decay channel, in which both Ws decay into a quark-antiquark pair, has the largest branching fraction of all t$\\bar{t}$ decay channels and is the only kinematically complete (i.e. neutrino-less) channel. It lacks, however, the clear isolated lepton signature and is therefore hard to distinguish from the multi-jet QCD background. It

  10. Measurement of W + gamma Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, Naho

    2005-03-01

    The production cross section and the kinematic properties of the decay products of W{gamma} in the W {yields} {mu}{nu} decay channel from p{bar p} collisions at {radical}s = 1.96 TeV are presented. The measurement use the high p{sub T} muon data from the upgraded Collider Detector at Fermilab (CDF). The data were collected between March 2002 and September 2003. The total integrated luminosities are 192 pb{sup -1} with the muon detector which covers the pseudorapidity region of |{eta}| {le} 0.6 and 175 pb{sup -1} with the muon detector covering the region 0.6 {le} |{eta}| {le} 1.0. In the Standard Model the {mu}{nu}{gamma} final states occur due to W{gamma} {yields} {mu}{nu}{gamma} production and via muon Bremsstrahlung, W {yields} {mu}{nu} {yields} {mu}{nu}{gamma}. W bosons are selected in their muon decay mode. Additionally, photons with transverse energy above 7 GeV, pseudorapidity in the central region (|{eta}| < 1.1) and muon-photon angular separation {Delta}R({mu},{gamma}) > 0.7 are selected. The author observes a total of 128 W{gamma} candidates, whereas the Standard Model expectation is 142.4 {+-} 9.5 events. The W{gamma} production cross section is found to be {sigma}(p{bar p} {yields} {mu}{nu}{gamma}) = 16.3 {+-} 2.3(stat.) {+-} 1.8(syst.) {+-} 1.2(lum.) [pb]. The theoretical prediction for this cross section is {sigma}(p{bar p} {yields} l{nu}{gamma}) = 19.3 {+-} 1.4(th.) [pb]. The Standard Model predictions for several kinematic + variables are compared with data for E{sub T}{sup {gamma}} > 7 GeV and {Delta}R({mu},{gamma}) > 0.7. The measured cross section and the photon and W boson production kinematics are found to agree with the Standard Model predictions.

  11. A novel antiproton radial diagnostic based on octupole induced ballistic loss

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page, R D; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y

    2008-01-01

    We report results from a novel diagnostic that probes the outer radial profile of trapped antiproton clouds. The diagnostic allows us to determine the profile by monitoring the time-history of antiproton losses that occur as an octupole field in the antiproton confinement region is increased. We show several examples of how this diagnostic helps us to understand the radial dynamics of antiprotons in normal and nested Penning-Malmberg traps. Better understanding of these dynamics may aid current attempts to trap antihydrogen atoms.

  12. Design of 2-4 GHz Equalizers for the Antiproton Accumulator Stacktail System

    Energy Technology Data Exchange (ETDEWEB)

    Deibele, C.; /Wisconsin U., Madison

    1999-01-01

    The antiproton source at Fermilab requires storage of antiprotons during the production of antiprotons. A fundamental part of the storage process involves stochastic cooling, which requires that the frequency spectrum from the pickups has notches at the revolution frequency and harmonics of the revolution frequency of the antiprotons in the storage ring. A system has been developed for broadband notches but suffers from dispersion. The dispersion inhibits the cooling process and therefore an equalizer is required. The process for designing the equalizers is described and results shown.

  13. Time-dependent density functional calculation of the energy loss of antiprotons colliding with metallic nanoshells

    Energy Technology Data Exchange (ETDEWEB)

    Quijada, M. [Departamento de Fisica de Materiales, Facultad de Quimicas UPV/EHU, Apartado 1072, 20080 San Sebastian (Spain); Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian (Spain); Borisov, A.G. [Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian (Spain); Universite Paris-Sud, Laboratoire des Collisions Atomiques et Moleculaires (France); CNRS, UMR 8625, Laboratoire des Collisions Atomiques et Moleculaires, LCAM, Batiment 351, UPS-11, Orsay, 91405 Orsay Cedex (France); Muino, R.D. [Donostia International Physics Center DIPC, P. Manuel de Lardizabal 4, 20018 San Sebastian (Spain); Centro de Fisica de Materiales, Centro Mixto CSIC-UPV/EHU, Edificio Korta, Avenida de Tolosa 72, 20018 San Sebastian (Spain)

    2008-06-15

    Time-dependent density functional theory is used to study the interaction between antiprotons and metallic nanoshells. The ground state electronic properties of the nanoshell are obtained in the jellium approximation. The energy lost by the antiproton during the collision is calculated and compared to that suffered by antiprotons traveling in metal clusters. The resulting energy loss per unit path length of material in thin nanoshells is larger than the corresponding quantity for clusters. It is shown that the collision process can be interpreted as the antiproton crossing of two nearly bi-dimensional independent metallic systems. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Modified Penning-Malmberg Trap for Storing Antiprotons

    Science.gov (United States)

    Sims, William H.; Martin, James; Lewis, Raymond

    2005-01-01

    A modified Penning-Malmberg trap that could store a small cloud of antiprotons for a relatively long time (weeks) has been developed. This trap is intended for use in research on the feasibility of contemplated future matter/antimatter-annihilation systems as propulsion sources for spacecraft on long missions. This trap is also of interest in its own right as a means of storing and manipulating antiprotons for terrestrial scientific experimentation. The use of Penning-Malmberg traps to store antiprotons is not new. What is new here is the modified trap design, which utilizes state-of-the-art radiofrequency (RF) techniques, including ones that, heretofore, have been used in radio-communication applications but not in iontrap applications. A basic Penning-Malmberg trap includes an evacuated round tube that contains or is surrounded by three or more collinear tube electrodes. A steady axial magnetic field that reaches a maximum at the geometric center of the tube is applied by an external source, and DC bias voltages that give rise to an electrostatic potential that reaches a minimum at the center are applied to the electrodes. The combination of electric and magnetic fields confines the charged particles (ions or electrons) for which it was designed to a prolate spheroidal central region. However, geometric misalignments and the diffusive cooling process prevent the steady fields of a basic Penning- Malmberg trap from confining the particles indefinitely. In the modified Penning-Malmberg trap, the loss of antiprotons is reduced or eliminated by use of a "rotating-wall" RF stabilization scheme that also heats the antiproton cloud to minimize loss by matter/antimatter annihilation. The scheme involves the superposition of a quadrupole electric field that rotates about the cylindrical axis at a suitably chosen radio frequency. The modified Penning-Malmberg trap (see Figure 1) includes several collinear sets of electrodes inside a tubular vacuum chamber. Each set

  15. View of the CERN Antiproton Decelerator (AD) and portrait of Prof. Tommy Eriksson, in charge of the AD machine.

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    The Antiproton Decelerator (AD) is a storage ring at the CERN laboratory in Geneva. It started operation in 2000. It decelerates antiprotons before sending them to several experiments studying antimatter : ALPHA, ASACUSA, ATRAP and ACE.

  16. First dose-map measured with a polycrystalline diamond 2D dosimeter under an intensity modulated radiotherapy beam

    Energy Technology Data Exchange (ETDEWEB)

    Scaringella, M., E-mail: scaringella@gmail.com [Università di Firenze, Dipartimento di Ingegneria dell’Informazione, Firenze (Italy); Zani, M. [INFN Sezione di Firenze, Sesto Fiorentino, Firenze (Italy); Università di Firenze, Dipartimento di Scienze Biomediche, Sperimentali e Cliniche, Firenze (Italy); Baldi, A. [Università di Firenze, Dipartimento di Ingegneria Industriale, Firenze (Italy); Bucciolini, M. [INFN Sezione di Firenze, Sesto Fiorentino, Firenze (Italy); Università di Firenze, Dipartimento di Scienze Biomediche, Sperimentali e Cliniche, Firenze (Italy); Pace, E.; Sio, A. de [INFN Sezione di Firenze, Sesto Fiorentino, Firenze (Italy); Università di Firenze, Dipartimento di Fisica e Astronomia, Sesto Fiorentino, Firenze (Italy); Talamonti, C. [INFN Sezione di Firenze, Sesto Fiorentino, Firenze (Italy); Università di Firenze, Dipartimento di Scienze Biomediche, Sperimentali e Cliniche, Firenze (Italy); Bruzzi, M. [INFN Sezione di Firenze, Sesto Fiorentino, Firenze (Italy); Università di Firenze, Dipartimento di Fisica e Astronomia, Sesto Fiorentino, Firenze (Italy)

    2015-10-01

    A prototype of bidimensional dosimeter made on a 2.5×2.5 cm{sup 2} active area polycrystalline Chemical Vapour Deposited (pCVD) diamond film, equipped with a matrix of 12×12 contacts connected to the read-out electronics, has been used to evaluate a map of dose under Intensity Modulated Radiation Therapy (IMRT) fields for a possible application in pre-treatment verifications of cancer treatments. Tests have been performed under a 6–10 MVRX beams with IMRT fields for prostate and breast cancer. Measurements have been taken by measuring the 144 pixels in different positions, obtained by shifting the device along the x/y axes to span a total map of 14.4×10 cm{sup 2}. Results show that absorbed doses measured by our pCVD diamond device are consistent with those calculated by the Treatment Planning System (TPS)

  17. State and Federal Regulatory measurement responsibilities around medical facilities. [Diagnostic x-ray, radioisotope, and radiotherapy facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lanzl, L.H.

    1976-01-01

    Radiation exposure to man is due chiefly to diagnostic x-ray procedures, in which radiation is intentionally directed toward a patient. Radiation therapy presents a lesser problem because a smaller percentage of the population is subjected to such treatment. Recently, some innovative steps were taken in the State of Illinois to reduce patient exposure in four diagnostic procedures without reducing the benefits derived therefrom. However, if these procedures are to be carried out properly, it is necessary to increase the precision and accuracy of radiation exposure measurements to the order of +-2 percent. The usual accuracy and precision of radiation protection measurements are of the order of +- 20 percent. Thus, should the Illinois radiation protection rules become widely adopted, the national dosimetry network will need to upgrade exposure measurement techniques. (auth)

  18. Radiotherapy of esthesioneuroblastoma. Radiotherapie beim Aesthesioneuroblastom

    Energy Technology Data Exchange (ETDEWEB)

    Strnad, V. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Grabenbauer, G.G. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Dunst, J. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik); Sauer, R. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik)

    1994-02-01

    From 1985 through 1990, twelve patients with estehesioneuroblastoma have been treated at the Department of Radiotherapy at the University of Erlangen. Two had Kadish stage A, one stage B, and nine stage C. There were seven males and five females with a mean age of 43 years. Eleven patients had combined trancranial-transbasal surgery prior to radiotherapy (five R0-, four R1-, and two patients R2-resections) and one received radiotherapy only. The dose was 12 to 60 Gy (mean 54 Gy) in 1.8 Gy to 2 Gy per fraction. 8/12 patients (67%) were locally controlled. One had progressive disease during radiotherapy after partial resection and died. Three had local recurrences, one in-field and two marginal. One patient with a local recurrence developed cervical lymph node metastases, and one locally controlled patient developed bone metastases but is alive eight years after chemotherapy plus radiotherapy for metastatic disease. The five-year-overall and recurrence-free survival was 72% and 55%, respectively. (orig./MG)

  19. Multiple collision effects on the antiproton production by high energy proton (100 GeV - 1000 GeV)

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroshi; Powell, J.

    1987-01-01

    Antiproton production rates which take into account multiple collision are calculated using a simple model. Methods to reduce capture of the produced antiprotons by the target are discussed, including geometry of target and the use of a high intensity laser. Antiproton production increases substantially above 150 GeV proton incident energy. The yield increases almost linearly with incident energy, alleviating space charge problems in the high current accelerator that produces large amounts of antiprotons.

  20. Measuring oxygen tension modulation, induced by a new pre-radiotherapy therapeutic, in a mammary window chamber mouse model

    Science.gov (United States)

    Schafer, Rachel; Gmitro, Arthur F.

    2015-03-01

    Tumor regions under hypoxic or low oxygen conditions respond less effectively to many treatment strategies, including radiation therapy. A novel investigational therapeutic, NVX-108 (NuvOx Pharma), has been developed to increase delivery of oxygen through the use of a nano-emulsion of dodecofluoropentane. By raising pO2 levels prior to delivering radiation, treatment efficacy may be improved. To aid in evaluating the novel drug, oxygen tension was quantitatively measured, spatially and temporally, to record the effect of administrating NVX-108 in an orthotopic mammary window chamber mouse model of breast cancer. The oxygen tension was measured through the use of an oxygen-sensitive coating, comprised of phosphorescent platinum porphyrin dye embedded in a polystyrene matrix. The coating, applied to the surface of the coverslip of the window chamber through spin coating, is placed in contact with the mammary fat pad to record the oxygenation status of the surface tissue layer. Prior to implantation of the window chamber, a tumor is grown in the SCID mouse model by injection of MCF-7 cells into the mammary fat pad. Two-dimensional spatial distributions of the pO2 levels were obtained through conversion of measured maps of phosphorescent lifetime. The resulting information on the spatial and temporal variation of the induced oxygen modulation could provide valuable insight into the optimal timing between administration of NVX-108 and radiation treatment to provide the most effective treatment outcome.

  1. Targeted tumor radiotherapy

    Directory of Open Access Journals (Sweden)

    Unak Perihan

    2002-01-01

    Full Text Available Targeted tumor radiotherapy is selectively delivery of curative doses of radiation to malignant sites. The aim of the targeted tumor radiotherapy is to use the radionuclides which have high LET particle emissions conjugated to appropriate carrier molecules. The radionuclides are selectively collected by tumor cells, depositing lethal doses to tumor cells while no admission occur to normal cells. In theory, targeted radiotherapy has several advantages over conventional radiotherapy since it allows a high radiation dose to be administered without causing normal tissue toxicity, although there are some limitations in the availability of appropriate targeting agents and in the calculations of administered doses. Therefore, for routine clinical applications more progress is still needed. In this article, the potential use of targeted tumor radiotherapy is briefly reviewed. More general aspects and considerations, such as potential radionuclides, mechanisms of tumor targeting was also outlined.

  2. An Analytical Model of Leakage Neutron Equivalent Dose for Passively-Scattered Proton Radiotherapy and Validation with Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Christopher; Newhauser, Wayne, E-mail: newhauser@lsu.edu [Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Baton Rouge, LA 70803 (United States); Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States); Farah, Jad [Institut de Radioprotection et de Sûreté Nucléaire, Service de Dosimétrie Externe, BP-17, 92262 Fontenay-aux-Roses (France)

    2015-05-18

    Exposure to stray neutrons increases the risk of second cancer development after proton therapy. Previously reported analytical models of this exposure were difficult to configure and had not been investigated below 100 MeV proton energy. The purposes of this study were to test an analytical model of neutron equivalent dose per therapeutic absorbed dose (H/D) at 75 MeV and to improve the model by reducing the number of configuration parameters and making it continuous in proton energy from 100 to 250 MeV. To develop the analytical model, we used previously published H/D values in water from Monte Carlo simulations of a general-purpose beamline for proton energies from 100 to 250 MeV. We also configured and tested the model on in-air neutron equivalent doses measured for a 75 MeV ocular beamline. Predicted H/D values from the analytical model and Monte Carlo agreed well from 100 to 250 MeV (10% average difference). Predicted H/D values from the analytical model also agreed well with measurements at 75 MeV (15% average difference). The results indicate that analytical models can give fast, reliable calculations of neutron exposure after proton therapy. This ability is absent in treatment planning systems but vital to second cancer risk estimation.

  3. Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

    CERN Document Server

    Amole, C; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Kurchaninov, L; Jonsell, S; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S

    2012-01-01

    Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antipr...

  4. Extra Low ENergy Antiproton (ELENA) ring and its Transfer Lines: Design Report

    CERN Document Server

    Alanzeau, C; Angoletta, M E; Baillie, J; Barna, D; Bartmann, W; Belochitskii, P; Borburgh, J; Breuker, H; Butin, F; Buzio, M; Capatina, O; Carli, C; Carlier, E; Cattin, M; Dobers, T; Chiggiato, P; Ducimetiere, L; Eriksson, T; Fedemann, S; Fowler, T; Froeschl, R; Gebel, R; Gilbert, N; Hancock, S; Harasimowicz, J; Hori, M; Jorgensen, L V; Kersevan, R; Kuchler, D; Lacroix, J M; LeGodec, G; Lelong, P; Lopez-Hernandez, L; Maury, S; Molendijk, J; Morand, B; Newborough, A; Nisbet, D; Nosych, A; Oelert, W; Paoluzzi, M; Pasinelli, S; Pedersen, F; Perini, D; Puccio, B; Sanchez-Quesada, J; Schoerling, D; Sermeus, L; Soby, L; Timmins, M; Tommasini, D; Tranquille, G; Vanbavinckhove, G; Vorozhtsov, A; Welsch, C; Zickler, T

    2014-01-01

    This Report gives a full description of the ELENA Ring to be built within the circumference of the Antiproton Decelarator (AD) Ring, in Building 193 at CERN. The ELENA ring will further decelerate the antiprotons coming from the AD at the momentum of 100 MeV/c down to 13.7 MeV/c, which corresponds to the kinetic energy of 100 keV before extracting to the physics experiments in the same building. The history of such an extra low energy antiproton ring at CERN goes a long way back, and even to the Decelerator’s previous incarnation, the Low Energy Antiproton Ring (LEAR), which came into operation in 1983. Already at that time, there were physics’ requests to further decelerate the antiprotons expected from LEAR by proposals for ELENA. Appendix I illustrates the cover pages of two such CERN documents from 1982.

  5. Theoretical motivation for gravitation experiments on ultra-low energy antiprotons and antihydrogen

    CERN Document Server

    Nieto, Michael Martin; Anderson, J D; Lau, E L; Pérez-Mercader, J; Nieto, Michael Martin; Goldman, T; Anderson, John D; Lau, Eunice L; Perez-Mercader, J

    1994-01-01

    We know that the generally accepted theories of gravity and quantum mechanics are fundamentally incompatible. Thus, when we try to combine these theories, we must beware of physical pitfalls. Modern theories of quantum gravity are trying to overcome these problems. Any ideas must confront the present agreement with general relativity, but yet be free to wonder about not understood phenomena, such as the dark matter problem and the anomalous spacecraft data which we announce here. This all has led some ``intrepid" theorists to consider a new gravitational regime, that of antimatter. Even more ``daring" experimentalists are attempting, or considering attempting, the measurement of the gravitational force on antimatter, including low-energy antiprotons and, perhaps most enticing, antihydrogen.

  6. Decay of Hot Nuclei at Low Spins Produced by Antiproton-Annihilation in Heavy Nuclei

    CERN Multimedia

    2002-01-01

    % PS208 \\\\ \\\\ The objective of the experiment is to study (i) the thermal excitation energy distribution of antiproton-induced reactions in heavy nuclei and (ii) the decay properties of hot nuclei at low spins via evaporation, multifragmentation and fission as a function of excitation energy. The experimental set-up consists of 4-$\\pi$ detectors: the Berlin Neutron Ball~(BNB) which is a spherical shell of gadolinium-loaded scintillator liquid with an inner and outer diameter of 40 and 160~cm, respectively. This detector counts the number of evaporated neutrons in each reaction. Inside BNB there is a 4-$\\pi$ silicon ball~(BSIB) with a diameter of 20~cm consisting of 162 detectors which measure energy and multiplicity of all emitted charged nuclear particles. The particles are identified via time of flight, energy and pulse shape correlations.

  7. Proton-Proton and Proton-Antiproton Colliders

    Science.gov (United States)

    Scandale, Walter

    2015-02-01

    In the last five decades, proton-proton and proton-antiproton colliders have been the most powerful tools for high energy physics investigations. They have also deeply catalyzed innovation in accelerator physics and technology. Among the large number of proposed colliders, only four have really succeeded in becoming operational: the ISR, the SppbarS, the Tevatron and the LHC. Another hadron collider, RHIC, originally conceived for ion-ion collisions, has also been operated part-time with polarized protons. Although a vast literature documenting them is available, this paper is intended to provide a quick synthesis of their main features and key performance.

  8. Proton-Proton and Proton-Antiproton Colliders

    CERN Document Server

    Scandale, Walter

    2014-01-01

    In the last five decades, proton–proton and proton–antiproton colliders have been the most powerful tools for high energy physics investigations. They have also deeply catalyzed innovation in accelerator physics and technology. Among the large number of proposed colliders, only four have really succeeded in becoming operational: the ISR, the SppbarS, the Tevatron and the LHC. Another hadron collider, RHIC, originally conceived for ion–ion collisions, has also been operated part-time with polarized protons. Although a vast literature documenting them is available, this paper is intended to provide a quick synthesis of their main features and key performance.

  9. Understanding Possible Proton-Antiproton Enhancement Observed by BES Collaboration

    Institute of Scientific and Technical Information of China (English)

    GAO Chong-Shou; ZHU Shi-Lin

    2004-01-01

    We comment on the quantum numbers and decay channels of the proton-antiproton enhancement observed by BES Collaboration. Based on the general symmetry consideration and available experimental information, we suggest that the quantum number of this possible signal is very likely to be JPC = 0-+, IG = O+, which cannot decay into final states π+π-, 2π0, KK, 3π. Besides its dissociation into pp, the other important mesonic decay modes could be ηππ, η'ππ, ηηη, 4π, KKπ, ηKK, KKππ, 6π. Experimental search of this signal in these meson final states is strongly called for.

  10. FAIR: The accelerator facility for antiproton and ion research

    Energy Technology Data Exchange (ETDEWEB)

    Sharkov, Boris [FAIR JCR GSI, Darmstad (Germany)

    2010-07-01

    This presentation outlines the current status of the facility for antiproton and ion research (FAIR). It is expected that the actual construction of the facility will commence in 2010 as the project has raised more than one billion euro in funding. The sequence and scope of the construction of the accelerator modules in accordance with modularized start version are described. Outstanding research opportunities offered by the modularized start version for all scientific FAIR communities from early on will allow to bridge the time until FAIR's completion with a world-leading research program. The green paper outlining a realistic path to achieve this goal is discussed.

  11. Antiprotonic potentials from global fits to the PS209 data

    Science.gov (United States)

    Friedman, E.; Gal, A.

    2004-01-01

    The experimental results for strong interaction effects in antiprotonic atoms by the PS209 collaboration consist of high quality data for several sequences of isotopes along the periodic table. Global analysis of these data in terms of a p¯-nucleus optical potential achieves good description of the data using a s-wave finite-range p¯N interaction. Equally good fits are also obtained with a poorly-defined zero-range potential containing a p-wave term.

  12. The W boson transverse momentum spectrum in proton-antiproton collisions at radical s = 1. 8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Winer, B.L.

    1991-02-01

    The Collider Detector at Fermilab (CDF) was used to measure the transverse momentum distribution of W boson produced in proton-antiproton collisions at the Tevatron collider. The W bosons were identified by the decay W {yields} e{nu}. The results are in good agreement with a next-to-leading order calculation. The cross section for W production with P{sub T} > 50 GeV/c is 423 {plus minus} 58 (stat.) {plus minus} 108 (sys.) pb. 58 refs., 53 figs., 16 tabs.

  13. D¯ D meson pair production in antiproton-nucleus collisions

    Science.gov (United States)

    Shyam, R.; Tsushima, K.

    2016-10-01

    We study the D ¯D (D¯0D0 and D-D+) charm meson pair production in antiproton (p ¯) induced reactions on nuclei at beam energies ranging from threshold to several GeV. Our model is based on an effective Lagrangian approach that has only the baryon-meson degrees of freedom and involves the physical hadron masses. The reaction proceeds via the t -channel exchanges of Λc+, Σc+, and Σc++ baryons in the initial collision of the antiproton with one of the protons of the target nucleus. The medium effects on the exchanged baryons are included by incorporating in the corresponding propagators, the effective charm baryon masses calculated within a quark-meson coupling (QMC) model. The wave functions of the bound proton have been determined within the QMC model as well as in a phenomenological model where they are obtained by solving the Dirac equation with appropriate scalar and vector potentials. The initial- and final-state distortion effects have been approximated by using an eikonal approximation-based procedure. Detailed numerical results are presented for total and double differential cross sections for the D¯0D0 and D-D+ production reactions on 16O and 90Zr targets. It is noted that at p ¯ beam momenta of interest to the P ¯ ANDA experiment, medium effects lead to noticeable enhancements in the charm meson production cross sections.

  14. Light meson emission in (anti)proton induced reactions

    CERN Document Server

    Kuraev, E A; Tomasi-Gustafsson, E

    2015-01-01

    Reactions induced by high energy antiprotons on proton on nuclei are accompanied with large probability by the emission of a few mesons. Interesting phenomena can be observed and QCD tests can be performed, through the detection of one or more mesons. The collinear emission from high energy (anti)proton beams of a hard pion or vector meson, can be calculated similarly to the emission of a hard photon from an electron \\cite{Kuraev:2013izz}. This is a well known process in QED, and it is called the "Quasi-Real Electron method", where the incident particle is an electron and a hard photon is emitted leaving an 'almost on shell' electron impinging on the target \\cite{Baier:1973ms}. Such process is well known as Initial State Emission (ISR) method of scanning over incident energy, and can be used, in the hadron case, to produce different kind of particles in similar kinematical conditions. In case of emission of a charged light meson, $\\pi$ or $\\rho$-meson, in proton-proton(anti-proton) collisions, the meson can b...

  15. EURAMET.RI(I)-S7 comparison of alanine dosimetry systems for absorbed dose to water measurements in gamma- and x-radiation at radiotherapy levels

    Science.gov (United States)

    Garcia, Tristan; Anton, Mathias; Sharpe, Peter

    2012-01-01

    The National Physical Laboratory (NPL), the Physikalisch-Technische Bundesanstalt (PTB) and the Laboratoire National Henri Becquerel (LNE-LNHB) are involved in the European project 'External Beam Cancer Therapy', a project of the European Metrology Research Programme. Within this project, the electron paramagnetic resonance (EPR)/alanine dosimetric method has been chosen for performing measurements in small fields such as those used in IMRT (intensity modulated radiation therapy). In this context, these three National Metrology Institutes (NMI) wished to compare the result of their alanine dosimetric systems (detector, modus operandi etc) at radiotherapy dose levels to check their consistency. This EURAMET.RI(I)-S7 comparison has been performed with the support of the Bureau International des Poids et Mesures (BIPM) which collected and distributed the results as a neutral organization, to ensure the comparison was 'blind'. Irradiations have been made under reference conditions by each laboratory in a 60Co beam and in an accelerator beam (10 MV or 12 MV) in a water phantom of 30 cm × 30 cm × 30 cm in a square field of 10 cm × 10 cm at the reference depth. Irradiations have been performed at known values of absorbed dose to water (Dw) within 10% of nominal doses of 5 Gy and 10 Gy, i.e. between 4.5 Gy and 5.5 Gy and between 9 Gy and 11 Gy, respectively. Each participant read out their dosimeters and assessed the doses using their own protocol (calibration curve, positioning device etc) as this comparison aims at comparing the complete dosimetric process. The results demonstrate the effectiveness of the EPR/alanine dosimetry systems operated by National Metrology Institutes as a method of assuring therapy level doses with the accuracy required. The maximum deviation in the ratio of measured to applied dose is less than 1%. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key

  16. Auger Emitter Based Radiotherapy- A Possible New Treatment for Cancer

    DEFF Research Database (Denmark)

    Fredericia, Pil; Groesser, Torsten; Severin, Gregory;

    2014-01-01

    damage produced by Low-LET radiation used in current radiotherapy (2-3) Considerable efforts have been made in the past twenty years to develop Auger emitter-based radiotherapy However, previous studies lack precise measurement of RBE, which is the fundamental factor defining the relationship between...

  17. Beam Dynamics Studies and Design Optimisation of New Low Energy Antiproton Facilities

    CERN Document Server

    Resta-Lopez, Javier; Welsch, Carsten P

    2016-01-01

    Antiprotons, stored and cooled at low energies in a storage ring or at rest in traps, are highly desirable for the investigation of a large number of basic questions on fundamental interactions. This includes the static structure of antiprotonic atomic systems and the time-dependent quantum dynamics of correlated systems. The Antiproton Decelerator (AD) at CERN is currently the worlds only low energy antiproton factory dedicated to antimatter experiments. New antiproton facilities, such as the Extra Low ENergy Antiproton ring (ELENA) at CERN and the Ultra-low energy Storage Ring (USR) at FLAIR, will open unique possibilities. They will provide cooled, high quality beams of extra-low energy antiprotons at intensities exceeding those achieved presently at the AD by factors of ten to one hundred. These facilities, operating in the energy regime between 100 keV down to 20 keV, face several design and beam dynamics challenges, for example nonlinearities, space charge and scattering effects limiting beam life time....

  18. Nanoparticle-guided radiotherapy

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing for simult...... for simultaneous or integrated external beam radiotherapy and imaging, e.g., using computed tomography (CT)....

  19. Differential cross section for W boson production as a function of transverse momentum in proton-antiproton collisions at 1.8 TeV

    CERN Document Server

    Abott, B; Abolins, M; Abramov, V; Acharya, B S; Adams, D L; Adams, M; Alves, G A; Amos, N; Anderson, E W; Baarmand, M M; Babintsev, V V; Babukhadia, L R; Bacon, Trevor C; Baden, A; Baldin, B Yu; Balm, P W; Todorova-Nová, S; Bantly, J; Barberis, E; Baringer, P; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Begel, M; Belyaev, A; Beri, S B; Bernardi, G; Bertram, I; Besson, A; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Bhattacharjee, M; Blazey, G C; Blessing, S; Böhnlein, A; Bozhko, N; Borcherding, F; Brandt, A; Breedon, R; Briskin, G M; Brock, R; Brooijmans, G; Bross, A; Buchholz, D; Bühler, M; Büscher, V; Burtovoi, V S; Butler, J M; Canelli, F; Carvalho, W S; Casey, D; Casilum, Z; Castilla-Valdez, H; Chakraborty, D; Chan, K M; Chekulaev, S V; Cho, D K; Choi, S; Chopra, S; Christenson, J H; Chung, M; Claes, D; Clark, A R; Cochran, J; Coney, L; Connolly, B; Cooper, W E; Coppage, D; Cummings, M A C; Cutts, D; Dahl, O I; Davis, G A; Davis, K; De, K; Del Signore, K; Demarteau, M; Demina, R; Demine, P; Denisov, D S; Denisov, S P; Desai, S V; Diehl, H T; Diesburg, M; DiLoreto, G; Doulas, S; Draper, P; Ducros, Y; Dudko, L V; Duensing, S; Duflot, L; Dugad, S R; Dyshkant, A; Edmunds, D; Ellison, J; Elvira, V D; Engelmann, R; Eno, S; Eppley, G; Ermolov, P; Eroshin, O V; Estrada, J K; Evans, H; Evdokimov, V N; Fahland, T; Fehér, S; Fein, D; Ferbel, T; Fisk, H E; Fisyak, Yu; Flattum, E M; Fleuret, F; Fortner, M R; Frame, K C; Fuess, S; Gallas, E J; Galjaev, A N; Gao, M; Gartung, P E; Gavrilov, V; Genik, R J; Genser, K; Gerber, C E; Gershtein, Yu; Gibbard, B; Gilmartin, R; Ginther, G; Gómez, B; Gómez, G; Goncharov, P I; González-Solis, J L; Gordon, H; Goss, L T; Gounder, K; Goussiou, A; Graf, N; Graham, G; Grannis, P D; Green, J A; Greenlee, H; Grinstein, S; Groer, L S; Grudberg, P M; Grünendahl, S; Sen-Gupta, A; Gurzhev, S N; Gutíerrez, G; Gutíerrez, P; Hadley, N J; Haggerty, H; Hagopian, S L; Hagopian, V; Hahn, K S; Hall, R E; Hanlet, P; Hansen, S; Hauptman, J M; Hays, C; Hebert, C; Hedin, D; Heinson, A P; Heintz, U; Heuring, T C; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoftun, J S; Hou, S; Huang, Y; Illingworth, R; Ito, A S; Jaffré, M; Jerger, S A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A M; Jones, M; Jöstlein, H; Juste, A; Kahn, S; Kajfasz, E; Karmanov, D E; Karmgard, D J; Kehoe, R; Kim, S K; Klima, B; Klopfenstein, C; Knuteson, B; Ko, W; Kohli, J M; Kostritskii, A V; Kotcher, J; Kotwal, A V; Kozelov, A V; Kozlovskii, E A; Krane, J; Krishnaswamy, M R; Krzywdzinski, S; Kubantsev, M A; Kuleshov, S; Kulik, Y; Kunori, S; Kuznetsov, V E; Landsberg, G L; Leflat, A; Leggett, C; Lehner, F; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J T; Lipton, R; Lucotte, A; Lueking, L H; Lundstedt, C; Luo, C; Maciel, A K A; Madaras, R J; Manankov, V; Mao, H S; Marshall, T; Martin, M I; Martin, R D; Mauritz, K M; May, B; Mayorov, A A; McCarthy, R; McDonald, J; McMahon, T; Melanson, H L; Meng, X C; Merkin, M; Merritt, K W B; Miao, C; Miettinen, H; Mihalcea, D; Mishra, C S; Mokhov, N V; Mondal, N K; Montgomery, H E; Moore, R W; Mostafa, M A; Da Motta, H; Nagy, E; Nang, F; Narain, M; Narasimham, V S; Neal, H A; Negret, J P; Negroni, S; Norman, D; Oesch, L H; Oguri, V; Olivier, B; Oshima, N; Padley, P; Pan, L J; Papageorgiou, K; Para, A; Parashar, N; Partridge, R; Parua, N; Paterno, M; Patwa, A; Pawlik, B; Perkins, J; Peters, M; Peters, O; Petroff, P; Piegaia, R; Piekarz, H; Pope, B G; Popkov, E; Prosper, H B; Protopopescu, S D; Qian, J; Quintas, P Z; Raja, R; Rajagopalan, S; Ramberg, E; Rapidis, P A; Reay, N W; Reucroft, S; Rha, J; Ridel, M; Rijssenbeek, M; Rockwell, T; Roco, M T; Rubinov, P M; Ruchti, R C; Santoro, A F S; Sawyer, L; Schamberger, R D; Schellman, H; Schwartzman, A; Sen, N; Shabalina, E; Shankar, H C; Shivpuri, R K; Shpakov, D; Shupe, M A; Sidwell, R A; Simák, V; Singh, H; Singh, J B; Sirotenko, V I; Slattery, P F; Smith, E; Smith, R P; Snihur, R; Snow, G A; Snow, J; Snyder, S; Solomon, J; Sorin, V; Sosebee, M; Sotnikova, N; Soustruznik, K; Souza, M; Stanton, N R; Steinbruck, G; Stephens, R W; Stevenson, M L; Stichelbaut, F; Stoker, D; Stolin, V; Stoyanova, D A; Strauss, M; Strovink, M; Stutte, L; Sznajder, A; Taylor, W; Tentindo-Repond, S; Thompson, J; Toback, D; Tripathi, S M; Trippe, T G; Turcot, A S; Tuts, P M; Van Gemmeren, P; Vaniev, V; Van Kooten, R; Varelas, N; Volkov, A A; Vorobev, A P; Wahl, H D; Wang, H; Wang, Z M; Warchol, J; Watts, G; Wayne, M; Weerts, H; White, A; White, J T; Whiteson, D; Wightman, J A; Wijngaarden, D A; Willis, S; Wimpenny, S J; Wirjawan, J V D; Womersley, J; Wood, D R; Yamada, R; Yamin, P; Yasuda, T; Yip, K; Youssef, S; Yu, J; Yu, Z; Zanabria, M E; Zheng, H; Zhou, Z; Zhu, Z H; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G; Zylberstejn, A

    2001-01-01

    We report a measurement of the differential cross section for W boson production as a function of its transverse momentum in proton-antiproton collisions at sqrt{s} = 1.8 TeV. The data were collected by the D0 experiment at the Fermilab Tevatron Collider during 1994-1995 and correspond to an integrated luminosity of 85 pb^{-1}. The results are in good agreement with quantum chromodynamics over the entire range of transverse momentum.

  20. Possibility of resonant capture of antiprotons by highly charged hydrogenlike ions

    Science.gov (United States)

    Genkin, M.; Lindroth, E.

    2009-02-01

    Recently, an experimental setup was proposed by Lapierre et al. [ Physics with ultra slow antiproton beams, AIP Conference Proceedings (2005), Vol. 793, p. 361] which would allow antiprotons and highly charged ions to collide repeatedly in an electron beam ion trap (EBIT) due to a nested trap configuration. As mentioned by the authors, such a setup may open the possibility to study antiproton capture into well-defined states through a resonant process which involves simultaneous electron excitation. In the present work, we give some theoretical estimations of the feasibility of that process.

  1. Understanding Possible Proton-Antiproton Enhancement Observed by BES Collaboration

    Institute of Scientific and Technical Information of China (English)

    GAOChong-Shou; ZHUShi-Lin

    2004-01-01

    We comment on the quantum numbers and decay channels of the proton-antiproton enhancement observed by BES Collaboration. Based on the general symmetry consideration and available experimental information, we suggest that the quantum number of this possible signal is very likely to be JPC=0-+, IG=0+, which cannot decay into final states π+π-, 2π0, K/%-K,3π. Besides its dissociation into p-p, the other important mesonic decay modes could be ηππ,η'ππ,ηηη, 4π, K-Kπ,ηK-K,K-Kππ, 6π. Experimental search of this signal in these meson final states is strongly called for.

  2. Fermilab Antiproton Source, Recycler Ring, and Main Injector

    CERN Document Server

    Nagaitsev, Sergei

    2014-01-01

    At the end of its operations in 2011, the Fermilab antiproton production complex consisted of a sophisticated target system, three 8-GeV storage rings (namely the Debuncher, the Accumulator and the Recycler), 25 independent multi-GHz stochastic cooling systems, the world's only relativistic electron cooling system and a team of technical experts equal to none. The accelerator complex at Fermilab supported a broad physics program including the Tevatron Collider Run II, neutrino experiments using 8-GeV and 120-GeV proton beams, as well as a test beam facility and other fixed target experiments using 120-GeV primary proton beams. This paper provides a brief description of Fermilab accelerators as they operated at the end of the Collider Run II (2011).

  3. Galactic cosmic-ray propagation in the light of AMS-02: Analysis of protons, helium, and antiprotons

    Science.gov (United States)

    Korsmeier, Michael; Cuoco, Alessandro

    2016-12-01

    We present novel constraints on cosmic-ray propagation in the Galaxy using the recent precise measurements of proton and helium spectra from AMS-02, together with preliminary AMS-02 data on the antiproton over proton ratio. To explore efficiently the large (up to 11-dimensional) parameter space we employ the nested-sampling algorithm as implemented in the MultiNest package, interfaced with the Galprop code to compute the model-predicted spectra. We use VOYAGER proton and helium data, sampling the local interstellar spectra, to constrain the solar modulation potential. We find that the turbulence of the Galactic magnetic field is well constrained, i.e., δ =0.3 0-0.02+0.03(stat )-0.04+0.10(sys ) , with uncertainties dominated by systematic effects. Systematic uncertainties are determined checking the robustness of the results to the minimum rigidity cut used to fit the data (from 1 GV to 5 GV), to the propagation scenario (convection vs no convection), and to the uncertainties in the knowledge of the antiproton production cross section. Convection and reacceleration are found to be degenerate and not well constrained singularly when using data above 5 GV. Using data above 1 GV reacceleration is required, vA=25 ±2 km /s , although this value might be significantly affected by the low-energy systematic uncertainty in the solar modulation. In a forthcoming companion paper, we investigate the constraints imposed by AMS-02 measurements on lithium, boron, and carbon.

  4. Symposium on Highlights from 14 years of LEAR Physics: "Light Antiprotonic Atoms" by R. Hayano

    CERN Multimedia

    1998-01-01

    Symposium on Highlights from 14 years of LEAR Physics hold at CERN, commemorating the closure of LEAR and giving a topical review of the impact of experiments with low energy antiprotons in their respective fields

  5. Symposium on Highlights from 14 years of LEAR Physics : "Antiproton Mass" by G. Gabrielse

    CERN Multimedia

    1998-01-01

    Symposium on Highlights from 14 years Physics hold at CERN, commemorating the closure of LEAR and giving a topical review of the impact of experiments with low energy antiprotons in their respective fields

  6. On the Utility of Antiprotons as Drivers for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, L J; Orth, C D; Tabak, M

    2003-10-20

    By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton beam required to penetrate to the desired annihilation point is always small relative to the deposited annihilation energy. We show that heavy metal seeding of the fuel and/or ablator is required to optimize local deposition of annihilation energy and determine that a minimum of {approx}3x10{sup 15} injected antiprotons will be required to achieve high yield (several hundred megajoules) in any target configuration. Target gains - i.e., fusion yields divided by the available p - {bar p} annihilation energy from the injected antiprotons (1.88GeV/{bar p}) - range from {approx}3 for volumetric ignition targets to {approx}600 for fast ignition targets. Antiproton-driven ICF is a speculative concept, and the handling of antiprotons and their required injection precision - temporally and spatially - will present significant technical challenges. The storage and manipulation of low-energy antiprotons, particularly in the form of antihydrogen, is a science in its infancy and a large scale-up of antiproton production over present supply

  7. Interaction of antiprotons with Rb atoms and a comparison of antiproton stopping powers of the atoms H, Li, Na, K, and Rb

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Fischer, Nicolas; Saenz, Alejandro

    2009-01-01

    Ionization and excitation cross sections as well as electron-energy spectra and stopping powers of the alkali metal atoms Li, Na, K, and Rb colliding with antiprotons were calculated using a time-dependent channel-coupling approach. An impact-energy range from 0.25 to 4000 keV was considered....... The target atoms are treated as effective one-electron systems using a model potential. The results are compared with calculated cross sections for antiproton-hydrogen atom collisions....

  8. Radiotherapy for the medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Gose, Kyuhei; Imajo, Yoshinari; Imanaka, Kazufumi (Kobe Univ. (Japan). School of Medicine)

    1983-08-01

    Eighteen patients with medulloblastoma, treated between 1972 and 1981, at Kobe University School of Medicine, were retrospectively studied. Of those completing post operative irradiation, 50% have survived for 2 years, 15% for 5 years and mean survival periods was 22.2 months. 13 out of 18 patients developed local recurrence and spinal dissemination. The mean time from the initial radiotherapy to recurrence was 8.5 months. It was suggested that posterior fossa should recieve 5,000 rad, the spine should 2,000 rad and recurrences should be treated by the combination of radiotherapy and chemotherapy.

  9. Xerostomia induced by radiotherapy

    Directory of Open Access Journals (Sweden)

    Alimi D

    2015-08-01

    Full Text Available David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have residual salivary gland function. Unfortunately, it is well established that in most cases radiotherapy destroys most of the salivary gland and associated salivary secretions.     

  10. Erythropoietin and radiotherapy; Erythropoietine et radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Le Fur, E.; Albarghach, M.N.; Pradier, O. [CHU de Morvan, Dept. de radiotherapie, 29 - Brest (France)

    2010-01-15

    Erythropoietin (E.P.O.) is a glycoprotein hormone. This hormone is a growth factor for red blood cells precursors in the bone marrow. The decrease of oxygen partial pressure, a reduced number of erythrocytes caused by bleeding or excessive destruction, or increased tissues oxygen requirements lead to increased secretion of E.P.O.. Its action takes place on bone marrow erythroblastic cells through specific receptors. E.P.O. stimulates the proliferation of red cell precursors stem cells in the bone marrow, thus increasing their production in one to two weeks. The effectiveness of E.P.O. at increasing haemoglobin and improving patients quality of life has been demonstrated by several studies. However, its use in radiotherapy remains controversial. While tumour hypoxia caused by anaemia is a factor of radio resistance and thus a source of local failure, tumour expression of E.P.O. receptors presents a significant risk for tumour progression and neo-angiogenesis, which would be increased during the administration of E.P.O.. The purpose of this article is to answer the question: is there a place for E.P.O. in combination with radiotherapy in the management of cancer?

  11. Radiotherapy for craniopharyngioma.

    Science.gov (United States)

    Aggarwal, Ajay; Fersht, Naomi; Brada, Michael

    2013-03-01

    Radiotherapy remains the mainstay of multidisciplinary management of patients with incompletely resected and recurrent craniopharyngioma. Advances in imaging and radiotherapy technology offer new alternatives with the principal aim of improving the accuracy of treatment and reducing the volume of normal brain receiving significant radiation doses. We review the available technologies, their technical advantages and disadvantages and the published clinical results. Fractionated high precision conformal radiotherapy with image guidance remains the gold standard; the results of single fraction treatment are disappointing and hypofractionation should be used with caution as long term results are not available. There is insufficient data on the use of protons to assess the comparative efficacy and toxicity. The precision of treatment delivery needs to be coupled with experienced infrastructure and more intensive quality assurance to ensure best treatment outcome and this should be carried out within multidisciplinary teams experienced in the management of craniopharyngioma. The advantages of the combined skills and expertise of the team members may outweigh the largely undefined clinical gain from novel radiotherapy technologies.

  12. Evaluation on Geant4 Hadronic Models for Pion Minus, Pion Plus and Neutron Particles as Major Antiproton Annihilation Products

    Science.gov (United States)

    Tavakoli, Mohammad Bagher; Mohammadi, Mohammad Mehdi; Reiazi, Reza; Jabbari, Keyvan

    2015-01-01

    Geant4 is an open source simulation toolkit based on C++, which its advantages progressively lead to applications in research domains especially modeling the biological effects of ionizing radiation at the sub-cellular scale. However, it was shown that Geant4 does not give a reasonable result in the prediction of antiproton dose especially in Bragg peak. One of the reasons could be lack of reliable physic model to predict the final states of annihilation products like pions. Considering the fact that most of the antiproton deposited dose is resulted from high-LET nuclear fragments following pion interaction in surrounding nucleons, we reproduced depth dose curves of most probable energy range of pions and neutron particle using Geant4. We consider this work one of the steps to understand the origin of the error and finally verification of Geant4 for antiproton tracking. Geant4 toolkit version 9.4.6.p01 and Fluka version 2006.3 were used to reproduce the depth dose curves of 220 MeV pions (both negative and positive) and 70 MeV neutrons. The geometry applied in the simulations consist a 20 × 20 × 20 cm3 water tank, similar to that used in CERN for antiproton relative dose measurements. Different physic lists including Quark-Gluon String Precompound (QGSP)_Binary Cascade (BIC)_HP, the recommended setting for hadron therapy, were used. In the case of pions, Geant4 resulted in at least 5% dose discrepancy between different physic lists at depth close to the entrance point. Even up to 15% discrepancy was found in some cases like QBBC compared to QGSP_BIC_HP. A significant difference was observed in dose profiles of different Geant4 physic list at small depths for a beam of pions. In the case of neutrons, large dose discrepancy was observed when LHEP or LHEP_EMV lists were applied. The magnitude of this dose discrepancy could be even 50% greater than the dose calculated by LHEP (or LHEP_EMV) at larger depths. We found that effect different Geant4 physic list in

  13. Evaluation on Geant4 Hadronic Models for Pion Minus, Pion Plus and Neutron Particles as Major Antiproton Annihilation Products.

    Science.gov (United States)

    Tavakoli, Mohammad Bagher; Mohammadi, Mohammad Mehdi; Reiazi, Reza; Jabbari, Keyvan

    2015-01-01

    Geant4 is an open source simulation toolkit based on C++, which its advantages progressively lead to applications in research domains especially modeling the biological effects of ionizing radiation at the sub-cellular scale. However, it was shown that Geant4 does not give a reasonable result in the prediction of antiproton dose especially in Bragg peak. One of the reasons could be lack of reliable physic model to predict the final states of annihilation products like pions. Considering the fact that most of the antiproton deposited dose is resulted from high-LET nuclear fragments following pion interaction in surrounding nucleons, we reproduced depth dose curves of most probable energy range of pions and neutron particle using Geant4. We consider this work one of the steps to understand the origin of the error and finally verification of Geant4 for antiproton tracking. Geant4 toolkit version 9.4.6.p01 and Fluka version 2006.3 were used to reproduce the depth dose curves of 220 MeV pions (both negative and positive) and 70 MeV neutrons. The geometry applied in the simulations consist a 20 × 20 × 20 cm(3) water tank, similar to that used in CERN for antiproton relative dose measurements. Different physic lists including Quark-Gluon String Precompound (QGSP)_Binary Cascade (BIC)_HP, the recommended setting for hadron therapy, were used. In the case of pions, Geant4 resulted in at least 5% dose discrepancy between different physic lists at depth close to the entrance point. Even up to 15% discrepancy was found in some cases like QBBC compared to QGSP_BIC_HP. A significant difference was observed in dose profiles of different Geant4 physic list at small depths for a beam of pions. In the case of neutrons, large dose discrepancy was observed when LHEP or LHEP_EMV lists were applied. The magnitude of this dose discrepancy could be even 50% greater than the dose calculated by LHEP (or LHEP_EMV) at larger depths. We found that effect different Geant4 physic list in

  14. Development of evaluation and performance verification technology for radiotherapy radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. Y.; Jang, S. Y.; Kim, B. H. and others

    2005-02-15

    No matter how much the importance is emphasized, the exact assessment of the absorbed doses administered to the patients to treat the various diseases such as lately soaring malignant tumors with the radiotherapy practices is the most important factor. In reality, several over-exposed patients from the radiotherapy practice become very serious social issues. Especially, the development of a technology to exactly assess the high doses and high energies (In general, dose administered to the patients with the radiotherapy practices are very huge doses, and they are about three times higher than the lethal doses) generated by the radiation generators and irradiation equipment is a competing issue to be promptly conducted. Over fifty medical centers in Korea operate the radiation generators and irradiation equipment for the radiotherapy practices. However, neither the legal and regulatory systems to implement a quality assurance program are sufficiently stipulated nor qualified personnel who could run a program to maintain the quality assurance and control of those generators and equipment for the radiotherapy practices in the medical facilities are sufficiently employed. To overcome the above deficiencies, a quality assurance program such as those developed in the technically advanced countries should be developed to exactly assess the doses administered to patients with the radiotherapy practices and develop the necessary procedures to maintain the continuing performance of the machine or equipment for the radiotherapy. The QA program and procedures should induce the fluent calibration of the machine or equipment with quality, and definitely establish the safety of patients in the radiotherapy practices. In this study, a methodology for the verification and evaluation of the radiotherapy doses is developed, and several accurate measurements, evaluations of the doses delivered to patients and verification of the performance of the therapy machine and equipment are

  15. [Radiotherapy for Graves' ophthalmopathy].

    Science.gov (United States)

    Kuhnt, T; Müller, A C; Janich, M; Gerlach, R; Hädecke, J; Duncker, G I W; Dunst, J

    2004-11-01

    Graves' ophthalmopathy (GO) is the most frequent extrathyroidal manifestation of Graves' disease, an autoimmune disorder of the thyroid, whereas the precise pathogenesis still remains unclear. In Hashimoto's thyroiditis the occurrence of proptosis is an extremely rare event. The therapy for middle and severe courses of GO shows in partly disappointing results, although several therapy modalities are possible (glucocorticoid therapy, radiotherapy, antithyroid drug treatment, surgery). All these therapies lead in only 40 - 70 % to an improvement of the pathogenic symptoms. An intensive interdisciplinary cooperation is necessary to satisfy the requirements for the treatment of Graves' ophthalmopathy. As a consequence of the very different results of the few of clinical studies that were accomplished with reference to this topic, treatment by radiotherapy in the management of the disease is presently controversially discussed. In the German-speaking countries the radiotherapy is, however, firmly established as a therapy option in the treatment of the moderate disease classes (class 2-5 according to NO SPECS), especially if diplopia is present. This article describes the sequences, dosages and fractionation schemes as well as the risks and side effects of the radiotherapy. Altogether, radiotherapy is assessed as an effective and sure method. The administration of glucocorticoids can take place before the beginning of or during the radiotherapy. For the success of treatment the correct selection of patients who may possibly profit from a radiotherapy is absolutely essential. By realising that GO proceeds normally over a period of 2-5 years, which is followed by a period of fibrotic alteration, the application of the radiotherapy in the early, active phase is indispensable. A precise explanation for the effects of radiotherapy in treatment of the GO does not exist at present. The determination of the most effective irradiation doses was made from retrospectively evaluated

  16. Tomodensitometry images: integration in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dessy, F.; Hoornaert, M.T. [Jolimont Hospital, Haine Saint Paul (France). Cancer and Nuclear Medicine Dept.; Malchair, F. [Biomed Engineering, Boncelles (France)

    1995-12-01

    With a view to utilization of CT scan images in radiotherapy, the effective energy and the linearity of four different scanners (Siemens somatom CR, HiQS, Plus and Picker PQ 2000) and two non standard scanners, simulators with CT option (Webb 1990) (Varian Ximatron and Oldelft Simulx CT) has been measured using the method described by White and Speller in 1980. When the linearity relation in presented using the density or the electron density as the abscissa, a blurred area where two different components of equal density or electron density can have two different Hounsfield`s numbers. Using the linearity relation, the density of Rando`s lung heterogeneity is determined. We calculated a treatment planning (TP) using this value and made a comparison between the TP and the real absorbed dose with was measured using diodes. The comparison between the TP and the relative Absorbed doses showed a difference of up to 4.5%.

  17. Properties of W + jet events in proton-antiproton collisions at 1.8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Drucker, R. B. [Lawrence Berkeley Lab., CA (United States); California Univ., Berkeley, CA (United States). Dept. of Physics

    1993-11-22

    W boson + QCD Jet events, produced in 1.8 TeV proton-antiproton collisions and measured by the Collider Detector at Fermilab (CDF), were used to measure the center-of-mass production angle of the W + jet system, and were also used to place limits on the production of excited quark states. The center-of-mass production angular distribution agrees well with leading order and next-to-leading order QCD predictions. Excited quark states were searched for in the reaction q + g {yields} q* {yields} q + W. Upper limits on the q* cross section, as a function of the q* mass, are shown. Comparison with a theoretical prediction for q* production excludes excited quark states with a mass in the range 150--530 GeV/c{sup 2}, at 95% confidence.

  18. Cooling of ions and antiprotons with magnetized electrons

    CERN Document Server

    Mollers, B; Walter, M; Zwicknagel, G; Carli, Christian; Nersisyan, H

    2004-01-01

    Electron cooling is a well-established method to improve the phase space quality of ion beams in storage rings. More recently antiprotons have been cooled in traps, first by electrons and then by positrons in order to produce antihydrogen atoms as simplest form of antimatter for CPT-tests. During these cooling processes the light particles are guided by strong external magnetic fields which imposes a challenge to the theoretical description. Within the binary collision model we treat the Coulomb interaction as second-order perturbation to the helix motion of the light particles and also by numerical simulations. In the complementary dielectric theory we calculate the polarization of the light particles by solving the nonlinear Vlasov-Poisson equation as well as linear response. It turns out that the linearization becomes dubious at low ion velocities. In the presence of a strong magnetic field the numerically expensive solution of the Vlasov-Poisson equation is the method of choice, alternatively one may empl...

  19. Constraining pre big-bang-nucleosynthesis expansion using cosmic antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Schelke, M. [Istituto Nazionale di Fisica Nucleare, Torino (Italy); Catena, R. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Fornengo, N. [Torino Univ. (Italy). Dipt. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Torino (Italy); Masiero, A. [Pavoa Univ. (Italy). Dipt. di Fisica]|[Istituto Nazionale di Fisica Nucleare, Padova (Italy); Pietroni, M. [Istituto Nazionale di Fisica Nucleare, Padova (Italy)

    2006-06-15

    A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity tests, may nevertheless lead to enhancements of the Hubble rate up to many orders of magnitude. In this paper we show that strong bounds on the pre-BBN evolution of the Universe may be derived, under the assumption that dark matter is a thermal relic, by combining the dark matter relic density bound with constraints coming from the production of cosmic-ray antiprotons by dark matter annihilation in the Galaxy. The limits we derive can be sizable and apply to the Hubble rate around the temperature of dark matter decoupling. For dark matter masses lighter than 100 GeV, the bound on the Hubble-rate enhancement ranges from a factor of a few to a factor of 30, depending on the actual cosmological model, while for a mass of 500 GeV the bound falls in the range 50-500. Uncertainties in the derivation of the bounds and situations where the bounds become looser are discussed. We finally discuss how these limits apply to some specific realizations of non-standard cosmologies: a scalar-tensor gravity model, kination models and a Randall-Sundrum D-brane model. (Orig.)

  20. Elastic scattering, polarization and absorption of relativistic antiprotons on nuclei

    CERN Document Server

    Larionov, A B

    2016-01-01

    We perform Glauber model calculations of the antiproton-nucleus elastic and quasielastic scattering and absorption in the beam momentum range $\\sim 0.5\\div10$ GeV/c. A good agreement of our calculations with available LEAR data and with earlier Glauber model studies of the $\\bar p A$ elastic scattering allows us to make predictions at the beam momenta of $\\sim 10$ GeV/c, i.e at the regime of the PANDA experiment at FAIR. The comparison with the proton-nucleus elastic scattering cross sections shows that the diffractive minima are much deeper in the $\\bar p A$ case due to smaller absolute value of the ratio of the real-to-imaginary part of the elementary elastic amplitude. Significant polarization signal for $\\bar p A$ elastic scattering at 10 GeV/c is expected. We have also revealed a strong dependence of the $\\bar p A$ absorption cross section on the slope parameter of the transverse momentum dependence of the elementary $\\bar pN$ amplitude. The $\\bar p A$ optical potential is discussed.

  1. Elastic scattering, polarization and absorption of relativistic antiprotons on nuclei

    Science.gov (United States)

    Larionov, A. B.; Lenske, H.

    2017-01-01

    We perform Glauber model calculations of the antiproton-nucleus elastic and quasielastic scattering and absorption in the beam momentum range ∼ 0.5 ÷ 10 GeV / c. A good agreement of our calculations with available LEAR data and with earlier Glauber model studies of the p bar A elastic scattering allows us to make predictions at the beam momenta of ∼10 GeV/c, i.e. at the regime of the PANDA experiment at FAIR. The comparison with the proton-nucleus elastic scattering cross sections shows that the diffractive minima are much deeper in the p bar A case due to smaller absolute value of the ratio of the real-to-imaginary part of the elementary elastic amplitude. Significant polarization signal for p bar A elastic scattering at 10 GeV/c is expected. We have also revealed a strong dependence of the p bar A absorption cross section on the slope parameter of the transverse momentum dependence of the elementary p bar N amplitude. The p bar A optical potential is discussed.

  2. Density functional theory investigation of antiproton-helium collisions

    CERN Document Server

    Henkel, N; Lüdde, H J; Kirchner, T; 10.1103/PhysRevA.80.032704

    2011-01-01

    We revisit recent developments in the theoretical foundations of time-dependent density functional theory (TDDFT). TDDFT is then applied to the calculation of total cross sections for ionization processes in the antiproton-Helium collision system. The Kohn-Sham potential is approximated as the sum of the Hartree-exchange potential and a correlation potential that was proposed in the context of laser-induced ionization. Furthermore, some approaches to the problem of calculating the ionization probabilities from the density are discussed. Small projectile energies below 5keV are considered as well as those in the range from 5 to 1000 keV. Results are compared with former calculations and with experimental data. We find that the correlation potential yields no obvious improvement of the results over the exchange-only approximation where the correlation potential is neglected. Furthermore, we find the problem of calculating the desired observables crucial, introducing errors of at least the same order of magnitud...

  3. Report on EUROMET.RI(I)-K1 and EUROMET.RI(I)-K4 (EUROMET project no. 813): Comparison of air kerma and absorbed dose to water measurements of {sup 60}Co radiation beams for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Csete, I. [National Office of Measures (OMH) - pilot laboratory and corresponding author (Hungary); Leiton, A.G. [Research Centre for Energy, Environment and Technology (CMRI-CIEMAT) (Spain); Sochor, V. [Czech Metrology Institute (CMI) (Czech Republic); Lapenas, A. [Latvian National Metrology Center (LNMC-RMTC) (Latvia); Grindborg, J.E. [Swedish Radiation Protection Authority (SSI) (Sweden); Jokelainen, I. [Radiation and Nuclear Safety Authority (STUK) (Finland); Bjerke, H. [Norwegian Radiation Protection Authority (NRPA) (Norway); Dobrovodsky, J. [Slovak Institute of Metrology (SMU) (Slovakia); Megzifene, A. [International Atomic Energy Agency, IAEA, Vienna (Austria); Hourdakis, C.J. [Hellenic Atomic Energy Committee (HAEC-HIRCL) (Greece); Ivanov, R. [National Centre of Metrology (NCM) (Bulgaria); Vekic, B. [Rudjer Boskovic Institute (IRB) (Croatia); Kokocinski, J. [Central Office of Measures (GUM) (Poland); Cardoso, J. [Institute for Nuclear Technology (ITN-LMRIR) (Portugal); Buermann, L. [Physikalisch Technische Bundesanstalt (PTB) (Germany); Tiefenboeck, W. [Bundesamt fur Eich und Vermesungswesen (BEV) (Austria); Stucki, G. [17 Bundesamt fur Metrologie (METAS) (Switzerland); Van Dijk, E. [NMi Van Swinden Laboratorium (NMi) (Netherlands); Toni, M.P. [ENEA-CR Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti (ENEA) (Italy); Minniti, R. [20 National Institute of Standards and Technology (NIST) (United States); McCaffrey, J.P. [National Research Council Canada (NRC) (Canada); Silva, C.N.M. [National Metrology Laboratory of Ionizing Radiation (LNMRI-IRD) (Brazil); Kharitonov, I. [D I Mendeleyev Institute for Metrology (VNIIM) (RU); Webb, D. [Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) (Australia); Saravi, M. [National Atomic Energy Commission (CNEA-CAE) (Argentina); Delaunay, F. [Laboratoire National Henri Becquerel (LNE-LNHB) (France)

    2010-06-15

    The results of an unprecedented international effort involving 26 countries are reported. The EUROMET.RI(I)-K1 and EUROMET.RI(I)-K4 key comparisons were conducted with the goal of supporting the relevant calibration and measurement capabilities (CMC) planned for publication by the participant laboratories. The measured quantities were the air kerma (K{sub air}) and the absorbed dose to water (Dw) in {sup 60}Co radiotherapy beams. The comparison was conducted by the pilot laboratory MKEH (Hungary), in a star-shaped arrangement from January 2005 to December 2008. The calibration coefficients of four transfer ionization chambers were measured using two electrometers. The largest deviation between any two calibration coefficients for the four chambers in terms of air kerma and absorbed dose to water was 2.7% and 3.3% respectively. An analysis of the participant uncertainty budgets enabled the calculation of degrees of equivalence (DoE), in terms of the deviations of the results and their associated uncertainties. As a result of this EUROMET project 813 comparison, the BIPM key comparison database (KCDB) will include eleven new Kair and fourteen new D{sub w} DoE values of European secondary standard dosimetry laboratories (SSDLs), and the KCDB will be updated with the new DoE values of the other participant laboratories. The pair-wise degrees of equivalence of participants were also calculated. In addition to assessing calibration techniques and uncertainty calculations of the participants, these comparisons enabled the experimental determinations of N{sub Dw}/N{sub Kair} ratios in the {sup 60}Co gamma radiation beam for the four radiotherapy transfer chambers. (authors)

  4. Radiotherapy of cutaneous lymphomas; Radiotherapie des lymphomes cutanes

    Energy Technology Data Exchange (ETDEWEB)

    Kirova, Y.M.; Piedbois, Y.; Pan, Q.; Guo, J.P.; Le Bourgeois, J.P. [Hopital Henri-Mondor, 94 - Creteil (France). Dept. de cancerologie

    1999-03-01

    Radiotherapy plays an important role in the treatment of cutaneous lymphomas. In the treatment of Mycosis fungoides, total skin electron beam radiation therapy is efficient for patients with limited and superficial forms of the disease. Radiotherapy is also efficient for the locally advanced forms of non-epidermo-tropic lymphomas. The palliative radiotherapy is indicated for advanced, nodular and treatment resistant forms of cutaneous lymphomas and for voluminous lymphadenopathies. (authors)

  5. A New Cancer Radiotherapy System Using Multi Robotic Manipulators

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Ho; Lee, Nam Ho; Lee, Byung Chul; Jeung, Kyung Min; Lee, Seong Uk; Bae, Yeong Geol; Na, Hyun Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The CyberKnife system is state-of-the-art cancer treatment equipment that combines an image tracking technique, artificial intelligence software, robot technology, accelerator technology, and treatment simulation technology. The current CyberKnife System has significant shortcomings. The biggest problem is that it takes a longer time to treat a tumor. A long treatment time gives stress to patients. Furthermore it makes the patients uncomfortable with radiation and thus it is difficult to measure the exact radiation dose rate to the tumor in the processing. Linear accelerators for radiation treatment are dependent on imports, and demand high maintenance cost. This also makes the treatment cost higher and prevents the popularization of radiation. To solve the disadvantages of the existing CyberKnife, a radiation treatment robot system applied to several articulated robots is suggested. Essential element techniques for new radiotherapy robot system are investigated and some problems of similar existing systems are analyzed. This paper presents a general configuration of a new radiation robot treatment system including with a quantitative goal of the requirement techniques. This paper described a new radiotherapy robot system to track the tumor using multiple articulated robots in real time. The existing CyberKnife system using a single robot arm has disadvantages of a long radiotherapy time, high medical fee, and inaccurate measurement of the radiotherapy dose. So a new radiotherapy robot system for tumors has been proposed to solve the above problems of conventional CyberKnife systems. Necessary technologies to configure new the radiotherapy robot system have been identified. Quantitative targets of each technology have been established. Multiple robot arms are adopted to decrease the radiotherapy time. The results of this research are provided as a requisite technology for a domestic radiotherapy system and are expected to be the foundation of new technology. The

  6. Multiple ionization of He, Ne, and Ar by fast protons and antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moller, S.P.; Sorensen, A.H.; Elsener, K.; Rensfelt, K.; Uggerhoj, E.

    1987-10-15

    Single and multiple ionization of He, Ne, and Ar has been studied experimentally by impact of fast protons and antiprotons. The single-ionization cross sections obtained with protons and antiprotons are found to be the same. The double-ionization cross sections obtained with antiprotons, however, are much larger than those obtained with protons at equal velocity. This difference is found for all three gases but the effect is largest for He and Ne, where the difference is about a factor of 2 at 1 MeV/amu. The difference is discussed in terms of interference between two collision mechanisms which both result in double-electron escape. Experimental information on the magnitude of the interference term is obtained by inclusion of double-ionization data, partly obtained in this work, for fast electron and ..cap alpha..-particle impact. For triple ionization of Ne, we also find that antiprotons yield much larger cross sections than protons do. Identical cross sections, however, are found for triple ionization of Ar with protons and antiprotons. This is believed to be due to the fact that triple ionization of Ar is mainly a consequence of a single vacancy produced in an inner shell followed by electronic rearrangement. This observation supports the interpretation that the observed charge effect is due to an interference effect in the outermost shell.

  7. Modeling of the Near-Earth Low-Energy Antiproton Fluxes

    Directory of Open Access Journals (Sweden)

    U. B. Jayanthi

    2011-01-01

    Full Text Available The local interstellar antiproton spectrum is simulated taking into account antineutron decay, (He,p interaction, secondary and tertiary antiproton production, and the solar modulation in the “force field” approximation. Inclusive invariant cross-sections were obtained through a Monte Carlo procedure using the Multistage Dynamical Model code simulating various processes of the particle production. The results of the simulations provided flux values of 4⋅10−3 to 10−2 and 10−2 to 1.7⋅10−2 antiprotons/(2 s sr GeV at energies of 0.2 and 1 GeV, respectively, for the solar maximum and minimum epochs. Simulated flux of the trapped antiprotons in the inner magnetosphere due to galactic cosmic ray (GCR interactions with the atmospheric constituents exceeds the galactic antiproton flux up to several orders. These simulation results considering the assumptions with the attendant limitations are in comprehensive agreement with the experimental data including the PAMELA ones.

  8. Evaluation of the shield calculation adequacy of radiotherapy rooms through Monte Carlo Method and experimental measures; Avaliacao da adequacao do calculo de blindagens de salas de radioterapia atraves do metodo de Monte Carlos e medidas experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Meireles, Ramiro Conceicao

    2016-07-01

    The shielding calculation methodology for radiotherapy services adopted in Brazil and in several countries is that described in publication 151 of the National Council on Radiation Protection and Measurements (NCRP 151). This methodology however, markedly employs several approaches that can impact both in the construction cost and in the radiological safety of the facility. Although this methodology is currently well established by the high level of use, some parameters employed in the calculation methodology did not undergo to a detailed assessment to evaluate the impact of the various approaches considered. In this work the MCNP5 Monte Carlo code was used with the purpose of evaluating the above mentioned approaches. TVLs values were obtained for photons in conventional concrete (2.35g / cm{sup 3}), considering the energies of 6, 10 and 25 MeV, respectively, first considering an isotropic radiation source impinging perpendicular to the barriers, and subsequently a lead head shielding emitting a shaped beam, in the format of a pyramid trunk. Primary barriers safety margins, taking in account the head shielding emitting photon beam pyramid-shaped in the energies of 6, 10, 15 and 18 MeV were assessed. A study was conducted considering the attenuation provided by the patient's body in the energies of 6,10, 15 and 18 MeV, leading to new attenuation factors. Experimental measurements were performed in a real radiotherapy room, in order to map the leakage radiation emitted by the accelerator head shielding and the results obtained were employed in the Monte Carlo simulation, as well as to validate the entire study. The study results indicate that the TVLs values provided by (NCRP, 2005) show discrepancies in comparison with the values obtained by simulation and that there may be some barriers that are calculated with insufficient thickness. Furthermore, the simulation results show that the additional safety margins considered when calculating the width of the

  9. Bottom Quark-antiquark Production And Mixing In Proton- Antiproton Collisions

    CERN Document Server

    Yu, Z

    2003-01-01

    The studies of bottom quark-antiquark production in proton-antiproton collisions play an important role in testing perturbative QCD. Measuring the mixing parameter of B mesons imposes constraints on the quark mixing (CKM) matrix and enhances the understanding of the Standard Model. Multi-GeV pp¯ colliders produce a significant amount of bb¯ pairs and thus enable studies in both of these fields. This thesis presents results of the bb¯ production cross section from pp¯ collisions at s = 1.8 TeV and the time-integrated average BB¯ mixing parameter &parl0;c&parr0; using high- mass dimuon data collected by CDF during its Run IB. There is a high concentration of muon pairs from inclusive semileptonic B decays in this data set. We take advantage of the long lifetime property of B hadrons and isolate the muons from B decays by studying the displacement of the muon pair trajectories. We use an Unbinned Maximum Likelihood Fitting method to fit the two dimensi...

  10. Exclusive Central $\\pi^{+}\\pi^{-}$ Production in Proton Antiproton Collisions at the CDF

    Energy Technology Data Exchange (ETDEWEB)

    Zurek, Maria [Julich, Forschungszentrum

    2015-01-01

    Exclusive $\\pi^{=}\\pi^{-}$ production in proton-antiproton collisions at $\\sqrt{s}$ = 0.9 and 1.96 TeV in the Collider Detector at Fermilab has been measured. We select events with two particles with opposite charge in pseudorapidity region -1.3 < $\\eta$ < 1.3 with no other particles detected in -5.9 < $\\eta$ < 5.9. Particles are assumed to be pions. The $\\pi^{+}\\pi^{-}$system is required to have rapidity -1.0 < $y$ < 1.0. The data are expected to be dominated by the double pomeron exchange mechanism. Therefore, the quantum numbers of the central state are constrained. The data extend up to dipion mass M($\\pi^{+}\\pi^{-}$) = 5000 MeV/$c^2$. Resonance structures consistent with $f_0$ and $f_2$(1270) mesons are visible. The results are valuable for light hadron spectroscopy and for providing information about the nature of the pomeron in a region between non-perturbative and perturbative quantum chromodynamics

  11. Ultrahigh Energy Cosmic Rays, The Diffuse High Energy Gamma Ray Background and Anti-protons

    CERN Document Server

    Eichler, David; Gavish, Eyal

    2016-01-01

    Theories for the origin of ultrahigh energy cosmic rays (UHECR) may imply a significant diffuse background in secondary $\\gamma$-rays from the pair cascads the UHECR initiate when interacting with background light. It is shown that, because the spectrum of these secondary $\\gamma$-rays is softer than the measured diffuse $\\gamma$-ray background in the 10-1000 GeV range, the addition of a hard component from the decay of TeV dark matter particles, subject to the implied constraints on its parameters, improves the fit. It is further argued that any compact astrophysical source of $\\bar p$s is unlikely to be as strong as decay of TeV dark matter particles, given bounds set by neutrino observations. The diffuse $\\gamma$-ray background presently sets the strongest lower bound on the lifetime of TeV dark matter particles, and hence on attendant anti-proton production, and further identification of other contributors to this background will further tighten these constraints.

  12. High-precision comparison of the antiproton-to-proton charge-to-mass ratio

    CERN Document Server

    Ulmer, S; Mooser, A; Franke, K; Nagahama, H; Schneider, G; Higuchi, T; Van Gorp, S; Blaum, K; Matsuda, Y; Quint, W; Walz, J; Yamazaki, Y

    2015-01-01

    Invariance under the charge, parity, time-reversal (CPT) transformation$^{1}$ is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry—that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime—although it is model dependent$^{2}$. A number of high-precision CPT and Lorentz invariance tests—using a co-magnetometer, a torsion pendulum and a maser, among others—have been performed$^{3}$, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available$^{4, 5, 6, 7, 8}$. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H$^−$) carried out in a Penning trap system. From 13,000 frequency measurements we compare th...

  13. Bayesian analysis of spatial-dependent cosmic-ray propagation: astrophysical background of antiprotons and positrons

    CERN Document Server

    Feng, Jie; Oliva, Alberto

    2016-01-01

    The AMS-02 experiment has reported a new measurement of the antiproton/proton ratio in Galactic cosmic rays (CRs). In the energy range $E\\sim\\,$60-450 GeV, this ratio is found to be remarkably constant. Using recent data on CR proton, helium, carbon, 10Be/9Be, and B/C ratio, we have performed a global Bayesian analysis based on a Markov-Chain Monte-Carlo sampling algorithm under a "two halo model" of CR propagation. In this model, CRs are allowed to experience a different type of diffusion when they propagate in the region close of the Galactic disk. We found that the vertical extent of this region is about 900 pc above and below the disk, and the corresponding diffusion coefficient scales with energy as $D\\sim\\,E^{0.15}$, describing well the observations on primary CR spectra, secondary/primary ratios and anisotropy. Under this model we have carried out improved calculations of antiparticle spectra arising from secondary CR production and their corresponding uncertainties. We made use of Monte-Carlo generato...

  14. Cosmic ray propagation in a diffusion model: a new estimation of the diffusion parameters and of the secondary antiprotons flux; Propagation des rayons cosmiques dans un modele de diffusion: une nouvelle estimation des parametres de diffusion et du flux d'antiprotons secondaires

    Energy Technology Data Exchange (ETDEWEB)

    Maurin, D

    2001-02-01

    Dark matter is present at numerous scale of the universe (galaxy, cluster of galaxies, universe in the whole). This matter plays an important role in cosmology and can not be totally explained by conventional physic. From a particle physic point of view, there exists an extension of the standard model - supersymmetry - which predicts under certain conditions the existence of new stable and massive particles, the latter interacting weakly with ordinary matter. Apart from direct detection in accelerators, various indirect astrophysical detection are possible. This thesis focuses on one particular signature: disintegration of these particles could give antiprotons which should be measurable in cosmic rays. The present study evaluates the background corresponding to this signal i. e. antiprotons produced in the interactions between these cosmic rays and interstellar matter. In particular, uncertainties of this background being correlated to the uncertainties of the diffusion parameter, major part of this thesis is devoted to nuclei propagation. The first third of the thesis introduces propagation of cosmic rays in our galaxy, emphasizing the nuclear reaction responsibles of the nuclei fragmentation. In the second third, different models are reviewed, and in particular links between the leaky box model and the diffusion model are recalled (re-acceleration and convection are also discussed). This leads to a qualitative discussion about information that one can infer from propagation of these nuclei. In the last third, we finally present detailed solutions of the bidimensional diffusion model, along with constrains obtained on the propagation parameters. The latter is applied on the antiprotons background signal and it concludes the work done in this thesis. The propagation code for nuclei and antiprotons used here has proven its ability in data analysis. It would probably be of interest for the analysis of the cosmic ray data which will be taken by the AMS experiment on

  15. Melanoma: Last call for radiotherapy.

    Science.gov (United States)

    Espenel, Sophie; Vallard, Alexis; Rancoule, Chloé; Garcia, Max-Adrien; Guy, Jean-Baptiste; Chargari, Cyrus; Deutsch, Eric; Magné, Nicolas

    2017-02-01

    Melanoma is traditionally considered to be a radioresistant tumor. However, radiotherapy and immunotherapy latest developments might upset this radiobiological dogma. Stereotactic radiotherapy allows high dose per fraction delivery, with high dose rate. More DNA lethal damages, less sublethal damages reparation, endothelial cell apoptosis, and finally clonogenic cell dysfunction are produced, resulting in improved local control. Radiotherapy can also enhance immune responses, inducing neoantigens formation, tumor antigen presentation, and cytokines release. A synergic effect of radiotherapy with immunotherapy is expected, and might lead to abscopal effects. If hadrontherapy biological properties seem able to suppress hypoxia-induced radioresistance and increase biological efficacy, ballistic advantages over photon radiations might also improve radiotherapy outcomes on usually poor prognosis locations. The present review addresses biological and clinical effects of high fraction dose, bystander effect, abscopal effect, and hadrontherapy features in melanoma. Clinical trials results are warranted to establish indications of innovative radiotherapy in melanoma.

  16. Antiproton–to–electron mass ratio determined by two-photon laser spectroscopy of antiprotonic helium atoms

    Directory of Open Access Journals (Sweden)

    Sótér A.

    2014-03-01

    Full Text Available The ASACUSA collaboration of CERN has recently carried out two-photon laser spectroscopy of antiprotonic helium atoms. Three transition frequencies were determined with fractional precisions of 2.3–5 parts in 109. By comparing the results with three-body QED calculations, the antiproton-to-electron mass ratio was determined as 1836.1526736(23.

  17. Energy-dependent partial-wave analysis of all antiproton-proton scattering data below 925 MeV/c

    NARCIS (Netherlands)

    Zhou, Daren; Timmermans, Rob G. E.

    2012-01-01

    Background: There is a renewed experimental interest in antiproton-proton scattering with an intense, possibly polarized antiproton beam. On the theoretical side, significant progress has been made in the understanding of the nuclear force from chiral effective field theory. Purpose: We provide a hi

  18. Radiotherapy of vertebral hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Kohichi; Hareyama, Masato; Oouchi, Atushi; Sido, Mitsuo; Nagakura, Hisayasu; Tamakawa, Mituharu; Akiba, Hidenari; Morita, Kazuo [Dept. of Radiology, Sapporo Medical Univ., School of Medicine (Japan)

    1997-12-31

    Between 1975 and 1996, 14 patients (11 females, 3 males) with vertebral hemangioma received treatment with radiotherapy. Thirteen patients had a history of back pain or lumbago and 2 patients had neurological symptoms such as sensory impairment or paraplegia. The standard dose administered was 36 Gy in 18 fractions (five treatments per week). In the 13 patients with pain, this was completely or partially relieved. The condition of a man with hypesthesia of the legs deteriorated and a woman with paraplegia who was treated with decompressive laminectomy followed by radiotherapy recovered completely after irradiation. CT scan before irradiation showed thickened trabeculae as small punctate areas of sclerosis in all patients. At MR imaging before irradiation, T2-weighted MR images showed areas of high intensity in all patients and MR images demonstrated lesion enhancement. However, none of the patients who were treated successfully with radiation demonstrated any changes of the affected vertebra in the conventional radiographic films, CT scan or MR imaging, even 5 years after irradiation. Radiological imaging is indispensable for the diagnosis of vertebral hemangiomas but does not appear to be useful for evaluating the effects of radiotherapy. (orig.).

  19. Meson Production in Proton-Proton and Antiproton - Interactions at Center of Mass Energy = 24.3 GEV

    Science.gov (United States)

    Singh, Vinay Mohan

    Experiment UA6 measured the inclusive production cross section of pi^0, eta, and omega mesons in the p_{T} range 3.5 to 6.1 GeV/c in the reactions;eqalignno {p + p&to M + Xcrnoalign{hbox {rm and}}|{p} + p& to M + Xcr}where M represents a meson and X any other associated particles, at center of mass energy sqrt{s} = 24.3 GeV. The experiment was located at the CERN SppS collider and utilized a fixed hydrogen gas jet as the target in oppositely circulating proton and antiproton beams of momenta 315 GeV/c. The apparatus could be rotated to select either proton-proton or antiproton-proton interactions. The meson production cross section results were obtained from the analysis of 3.7 inverse picobarns (pb ^{-1}) of pp data collected in 1988 and 3.2 pb^{-1} of pp data collected in 1989. The eta/pi ^0 production ratio is measured to be 0.61 +/- 0.03 +/- 0.07 for pp and 0.62 +/- 0.03 +/- 0.07 for pp. The omega/ pi^0 production ratio is measured to be 0.87 +/- 0.16 +/- 0.13 for pp and 0.84 +/- 0.16 +/- 0.13 for pp. The inclusive pi^0 cross section is determined as a function of p_{T} averaged over the rapidity range 0.6 <= y <= 1.2. Comparison of the production between pp and pp reveals no significant difference. The cross section and production ratios are also compared with results from other experiments and found to be in agreement.

  20. TU-G-BRA-04: Changes in Regional Lung Function Measured by 4D-CT Ventilation Imaging for Thoracic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y; Kadoya, N [Tohoku University School of Medicine, Sendai, Miyagi (Japan); Kabus, S [Philips Research Europe, Hamburg, Hamburg (Germany); Loo, B [Stanford University, Stanford, CA (United States); Keall, P [University of Sydney, Camperdown (Australia); Yamamoto, T [University of California Davis School of Medicine, Sacramento, CA (United States)

    2015-06-15

    Purpose: To test the hypothesis: 4D-CT ventilation imaging can show the known effects of radiotherapy on lung function: (1) radiation-induced ventilation reductions, and (2) ventilation increases caused by tumor regression. Methods: Repeat 4D-CT scans (pre-, mid- and/or post-treatment) were acquired prospectively for 11 thoracic cancer patients in an IRB-approved clinical trial. A ventilation image for each time point was created using deformable image registration and the Hounsfield unit (HU)-based or Jacobian-based metric. The 11 patients were divided into two subgroups based on tumor volume reduction using a threshold of 5 cm{sup 3}. To quantify radiation-induced ventilation reduction, six patients who showed a small tumor volume reduction (<5 cm{sup 3}) were analyzed for dose-response relationships. To investigate ventilation increase caused by tumor regression, two of the other five patients were analyzed to compare ventilation changes in the lung lobes affected and unaffected by the tumor. The remaining three patients were excluded because there were no unaffected lobes. Results: Dose-dependent reductions of HU-based ventilation were observed in a majority of the patient-specific dose-response curves and in the population-based dose-response curve, whereas no clear relationship was seen for Jacobian-based ventilation. The post-treatment population-based dose-response curve of HU-based ventilation demonstrated the average ventilation reductions of 20.9±7.0% at 35–40 Gy (equivalent dose in 2-Gy fractions, EQD2), and 40.6±22.9% at 75–80 Gy EQD2. Remarkable ventilation increases in the affected lobes were observed for the two patients who showed an average tumor volume reduction of 37.1 cm{sup 3} and re-opening airways. The mid-treatment increase in HU-based ventilation of patient 3 was 100.4% in the affected lobes, which was considerably greater than 7.8% in the unaffected lobes. Conclusion: This study has demonstrated that 4D-CT ventilation imaging shows

  1. Health-related quality of life measurement in long-term survivors and outcome following radical radiotherapy for localized prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Galalae, R.M.; Riemer, B.; Kimmig, B.; Kovacs, G. [Dept. of Radiation Therapy (Radiooncology), Univ. Hospital Schleswig-Holstein, Kiel (Germany); Loch, T. [Dept. of Urology, Univ. of Homburg/Saar, Homburg/Saar (Germany); Rzehak, P. [Dept. of Epidemiology, Univ. of Ulm, Ulm (Germany); Kuechler, T. [Dept. of Surgery, Univ. Hospital Schleswig-Holstein, Kiel (Germany)

    2004-09-01

    Purpose: to report long-term outcomes in terms of health-related quality of life (HRQoL) and survival of a dose-escalating radiotherapy protocol and to validate a new disease-specific HRQoL instrument. Patients and methods: 189 consecutive men with prostate cancer were analyzed; 127 patients had T1-2 (1% T1, 66% T2) and 62 patients (33%) T3 tumors. The pelvic lymphatics were treated to a dose of 50 Gy by external-beam irradiation. The prostate dose was limited to 40 Gy using compensators. The prostate was treated to the total nominal dose of 70 Gy using high-dose-rate (HDR) brachytherapy. The fraction dose was 15 Gy in the McNeal zone (planning target volume [PTV] 1), while 8-9 Gy were applied in the entire prostate (PTV 2). The HRQoL of the 145 long-term survivors was assessed using the EORTC QLQ-C30 and a new prostate-specific instrument (PSM-G 1.0). The reliability of the instruments used and HRQoL scale scores were calculated. Uni-/multivariate analyses of variance were performed. Results: at a mean follow-up of 6.5 years 86.3% of the patients were disease-free, and 78% were biochemically controlled. The mean Cronbach's {alpha}-values were 0.81 for the QLQ-C30, and 0.74 for the prostate-specific module. Univariate analyses of variance by T-stage, grading, prostata-specific antigen (PSA) status after therapy and adjuvant androgen suppression (AS) revealed that PSA elevation after irradiation and AS were associated with significantly diminished HRQoL. In multivariate analyses AS significantly lowered the HRQoL without survival benefit. Conclusion: the described radiotherapy regimen represents a curative and well-tolerated treatment for localized prostate cancer. The HRQoL assessment with both instruments used was reliable. Adjuvant AS and PSA elevation were associated with diminished HRQoL. (orig.)

  2. A fussy revisitation of antiprotons as a tool for Dark Matter searches

    CERN Document Server

    Boudaud, Mathieu

    2015-01-01

    Antiprotons are regarded as a powerful probe for Dark Matter (DM) indirect detection and indeed current data from \\PAMELA\\ have been shown to lead to stringent constraints. However, in order to exploit their constraining/discovery power properly, great attention must be put into effects (linked to their propagation in the Galaxy) which may be perceived as subleading but actually prove to be quite relevant. We revisit the computation of the astrophysical background and of the DM antiproton fluxes fully including the effects of: diffusive reacceleration, energy losses including tertiary component and solar modulation (in a force field approximation). Using the updated proton and helium fluxes just released by the \\AMS\\ experiment we reevaluate the secondary astrophysical antiproton to proton ratio and its uncertainties, and compare it with the ratio preliminarly reported by \\AMS. We find no unambiguous evidence for a significant excess with respect to expectations. Yet, some preference for a flatter energy depe...

  3. Non-Gaussian beam dynamics in low energy antiproton storage rings

    Science.gov (United States)

    Resta-López, J.; Hunt, J. R.; Welsch, C. P.

    2016-10-01

    In low energy antiproton facilities, where electron cooling is fundamental, the cooling forces together with heating phenomena causing emittance blow-up, such as Intra Beam Scattering (IBS), result in highly non-Gaussian beam distributions. In these cases, a precise simulation of IBS effects is essential to realistically evaluate the long term beam evolution, taking into account the non-Gaussian characteristics of the beam. Here, we analyse the beam dynamics in the Extra Low ENergy Antiproton ring (ELENA), which is a new small synchrotron currently being constructed at CERN to decelerate antiprotons to energies as low as 100 keV. Simulations are performed using the code BETACOOL, comparing different models of IBS.

  4. Classification of high-energy antiprotons on electrons background based on calorimeter data in PAMELA experiment

    Science.gov (United States)

    Dunaeva, O. A.; Alekseev, V. V.; Bogomolov, Yu V.; Lukyanov, A. D.; Malakhov, V. V.; Mayorov, A. G.; Rodenko, S. A.

    2017-01-01

    In modern experimental physics a heterogeneous coordinate-sensitive calorimeters are widely used due to their good characteristics and possibilities to obtain a three-dimensional information of particles interactions. Especially it is important at high-energies when electromagnetic or hadron showers are arise. We propose a quit efficient method to identify antiprotons (positrons) with energies more than 10 GeV on electron (proton) background by calorimeter of such kind. We construct the AdaBoost classifier and SVM to separate particles into two classes, different combinations of energy release along reconstructed particle trajectory were used as feature vector. We test a preliminary version of the method on a calorimeter of the PAMELA magnetic spectrometer. For high-energy particles we got a good quality of classification: it lost about 5 · 10‑2 of antiprotons, and less than 4 · 10‑4 of electrons were classified to antiproton class.

  5. Antiproton signatures from astrophysical and dark matter sources at the galactic center

    CERN Document Server

    Cembranos, J A R; Maroto, A L

    2015-01-01

    The center of our Galaxy is a complex region characterized by extreme phenomena. The presence of the supermassive Sagittarius A* black hole, a high Dark Matter density and an even higher baryonic density are able to produce very energetic processes. Indeed, high energetic gamma rays have been observed by different telescopes, although its origin is not clear. In this work, we constrain the possible antiproton flux component associated to this signal. The expected secondary astrophysical antiproton background already saturates the observed data. It implies that any other important astrophysical source leads to an inconsistent excess, since the theoretical uncertainties corresponding to the mentioned background are small. The constraints depend on the diffusion model and the spectral features of the source. In particular, we consider antiproton spectra described by a power-law, a monochromatic signal and a Standard Model particle-antiparticle channel production.

  6. Advanced space propulsion study - antiproton and beamed-power propulsion. Final report, 1 May 1986-30 June 1987

    Energy Technology Data Exchange (ETDEWEB)

    Forward, R.L.

    1987-10-01

    The contract objective was to monitor the research at the forefront of physics and engineering to discover new spacecraft-propulsion concepts. The major topics covered were antiproton-annihilation propulsion, laser thermal propulsion, laser-pushed lightsails, tether transportation systems, solar sails, and metallic hydrogen. Five papers were prepared and are included as appendices. They covered 1) pellet, microwave, and laser-beamed power systems for interstellar transport; 2) a design for a near-relativistic laser-pushed lightsail using near-term laser technology; 3) a survey of laser thermal propulsion, tether transportation systems, antiproton annihilation propulsion, exotic applications of solar sails, and laser-pushed interstellar lightsails; 4) the status of antiproton annihilation propulsion as of 1986, and 5) the prospects for obtaining antimatter ions heavier than antiprotons. Two additional appendices contain the first seven issues of the Mirror Matter Newsletter concerning the science and technology of antimatter, and an annotated bibliography of antiproton science and technology.

  7. Midrapidity antiproton-to-proton ratio from Au+Au collisions at sqrt [s(NN)]=130 GeV.

    Science.gov (United States)

    Adler, C; Ahammed, Z; Allgower, C; Anderson, M; Averichev, G S; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellwied, R; Berger, J; Bichsel, H; Bland, L C; Blyth, C O; Bonner, B E; Bossingham, R; Boucham, A; Brandin, A; Caines, H; de la Barca Sánchez, M C; Cardenas, A; Carroll, J; Castillo, J; Castro, M; Cebra, D; Chattopadhyay, S; Chen, M L; Chen, Y; Chernenko, S P; Cherney, M; Chikanian, A; Choi, B; Christie, W; Coffin, J P; Conin, L; Cormier, T M; Cramer, J G; Crawford, H J; DeMello, M; Deng, W S; Derevschikov, A A; Didenko, L; Draper, J E; Dunin, V B; Dunlop, J C; Eckardt, V; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Fachini, P; Ferguson, M I; Finch, E; Fisyak, Y; Flierl, D; Foley, K J; Gagunashvili, N; Gans, J; Germain, M; Geurts, F; Ghazikhanian, V; Grabski, J; Grachov, O; Greiner, D; Grigoriev, V; Gushin, E; Hallman, T J; Hardtke, D; Harris, J W; Heffner, M; Heppelmann, S; Herston, T; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horsley, M; Huang, H Z; Humanic, T J; Hümmler, H; Igo, G J; Ishihara, A; Ivanshin, Y I; Jacobs, P; Jacobs, W W; Janik, M; Johnson, I; Jones, P G; Judd, E; Kaneta, M; Kaplan, M; Keane, D; Khodinov, A; Kisiel, A; Klay, J; Klein, S R; Klyachko, A; Konstantinov, A S; Kotchenda, L; Kovalenko, A D; Kramer, M; Kravtsov, P; Krueger, K; Kuhn, C; Kulikov, A I; Kunde, G J; Kunz, C L; Kutuev, R K; Kuznetsov, A A; Lamas-Valverde, J; Lamont, M A; Landgraf, J M; Lange, S; Lansdell, C P; Lasiuk, B; Laue, F; Lebedev, A; LeCompte, T; Leontiev, V M; Leszczynski, P; LeVine, M J; Li, Q; Li, Q; Lindenbaum, S J; Lisa, M A; Ljubicic, T; Llope, W J; LoCurto, G; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Lynn, D; Madansky, L; Majka, R; Maliszewski, A; Margetis, S; Martin, L; Marx, J; Matis, H S; Matulenko, Y A; McShane, T S; Melnick, Y; Meschanin, A; Milosevich, Z; Minaev, N G; Mitchell, J; Moiseenko, V A; Moltz, D; Moore, C F; Morozov, V; de Moura, M M; Munhoz, M G; Mutchler, G S; Nelson, J M; Nevski, P; Nikitin, V A; Nogach, L V; Norman, B; Nurushev, S B; Nystrand, J; Odyniec, G; Ogawa, A; Ogilvie, C A; Oldenburg, M; Olson, D; Paic, G; Pandey, S U; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Perevoztchikov, V; Peryt, W; Petrov, V A; Pinganaud, W; Platner, E; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potrebenikova, E; Prindle, D; Pruneau, C; Radomski, S; Rai, G; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Roy, C; Russ, D; Rykov, V; Sakrejda, I; Sandweiss, J; Saulys, A C; Savin, I; Schambach, J; Scharenberg, R P; Schmitz, N; Schroeder, L S; Schüttauf, A; Seger, J; Seliverstov, D; Seyboth, P; Shestermanov, K E; Shimanskii, S S; Shvetcov, V S; Skoro, G; Smirnov, N; Snellings, R; Sowinski, J; Spinka, H M; Srivastava, B; Stephenson, E J; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Stroebele, H; Struck, C; Suaide, A A; Sugarbaker, E; Suire, C; Symons, T J; Szanto de Toledo, A; Szarwas, P; Takahashi, J; Tang, A H; Thomas, J H; Tikhomirov, V; Trainor, T; Trentalange, S; Tokarev, M; Tonjes, M B; Trofimov, V; Tsai, O; Turner, K; Ullrich, T; Underwood, D G; Van Buren, G; VanderMolen, A M; Vanyashin, A; Vasilevski, I M; Vasiliev, A N; Vigdor, S E; Voloshin, S A; Wang, F; Ward, H; Wells, R; Wenaus, T; Westfall, G D; Whitten, C; Wieman, H; Willson, R; Wissink, S W; Witt, R; Xu, N; Xu, Z; Yakutin, A E; Yamamoto, E; Yang, J; Yepes, P; Yokosawa, A; Yurevich, V I; Zanevski, Y V; Zhang, J; Zhang, W M; Zoulkarneev, R; Zubarev, A N

    2001-05-21

    We report results on the ratio of midrapidity antiproton-to-proton yields in Au+Au collisions at sqrt[s(NN)] = 130 GeV per nucleon pair as measured by the STAR experiment at RHIC. Within the rapidity and transverse momentum range of /y/<0.5 and 0.4

  8. Observation and study of bottom-meson decays to a charm meson, a proton-antiproton pair, and pions

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tae Min [Univ. of California, Santa Barbara, CA (United States)

    2010-04-27

    Bottom-meson decays with baryons show two unusual features—the branching fractions are enhanced for multibody decays and the baryon-antibaryon subsystem recoils against the other decay products—and their reasons are not yet well understood. Moreover, measurements using explicit reconstruction techniques constitute only about 1% out of about 8% of such decays. This Dissertation reports the study of ten bottom-meson decays (labeled 0– 9) to a proton-antiproton pair, a charm meson, and a system of up to two pions, using the BABAR Experiment’s 455×106 BB pairs produced with the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center.

  9. Design and optimisation of low heat load liquid helium cryostat to house cryogenic current comparator in antiproton decelerator at CERN

    Science.gov (United States)

    Lees, A.; Koettig, T.; Fernandes, M.; Tan, J.

    2017-02-01

    The Cryogenic Current Comparator (CCC) is installed in the low-energy Antiproton Decelerator (AD) at CERN to make an absolute measurement of the beam intensity. Operating below 4.2 K, it is based on a superconducting quantum interference device (SQUID) and employs a superconducting niobium shield to supress magnetic field components not linked to the beam current. The AD contains no permanent cryogenic infrastructure so the local continuous liquefaction of helium using a pulse-tube is required; limiting the available cooling power to 0.69 W at 4.2K. Due to the sensitivity of the SQUID to variations in magnetic fields, the CCC is highly sensitive to mechanical vibration which is limited to a minimum by the support systems of the cryostat. This article presents the cooling system of the cryostat and discusses the design challenges overcome to minimise the transmission of vibration to the CCC while operating within the cryogenic limits imposed by the cooling system.

  10. Beam-energy dependence of the directed flow of protons, antiprotons, and pions in Au+Au collisions.

    Science.gov (United States)

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Levine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-04-25

    Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

  11. Beam-Energy Dependence of Directed Flow of Protons, Antiprotons and Pions in Au+Au Collisions

    CERN Document Server

    Adamczyk, L; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Sánchez, M Calderón de la Barca; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Leyva, A Davila; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; de Souza, R Derradi; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Don, D M M D Madagodagettige; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen,, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-01-01

    Rapidity-odd directed flow($v_1$) measurements for charged pions, protons and antiprotons near mid-rapidity ($y=0$) are reported in $\\sqrt{s_{NN}} =$ 7.7, 11.5, 19.6, 27, 39, 62.4 and 200 GeV Au + Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). At intermediate impact parameters, the proton and net-proton slope parameter $dv_1/dy|_{y=0}$ shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton $dv_1/dy|_{y=0}$ changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

  12. Design and test of a scintillation dosimeter for dosimetry measurements of high energy radiotherapy beams; Conception et realisation d'un dosimetre a scintillation adapte a la dosimetrie de faisceaux de rayonnements ionisants en faisceaux de rayonnements ionisants en radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Fontbonne, J.M

    2002-12-01

    This work describes the design and evaluation of the performances of a scintillation dosimeter developed for the dosimetry of radiation beams used in radiotherapy. The dosimeter consists in a small plastic scintillator producing light which is guided by means of a plastic optical fiber towards photodetectors. In addition to scintillation, high energy ionizing radiations produce Cerenkov light both in the scintillator and the optical fiber. Based on a wavelength analysis, we have developed a deconvolution technique to measure the scintillation light in the presence of Cerenkov light. We stress the advantages that are anticipated from plastic scintillator, in particular concerning tissue or water equivalence (mass stopping power, mass attenuation or mass energy absorption coefficients). We show that detectors based on this material have better characteristics than conventional dosimeters such as ionisation chambers or silicon detectors. The deconvolution technique is exposed, as well as the calibration procedure using an ionisation chamber. We have studied the uncertainty of our dosimeter. The electronics noise, the fiber transmission, the deconvolution technique and the calibration errors give an overall combined experimental uncertainty of about 0,5%. The absolute response of the dosimeter is studied by means of depth dose measurements. We show that absolute uncertainty with photons or electrons beams with energies ranging from 4 MeV to 25 MeV is less than {+-} 1 %. Last, at variance with other devices, our scintillation dosimeter does not need dose correction with depth. (author)

  13. The experiment PANDA: physics with antiprotons at FAIR

    Science.gov (United States)

    Boca, Gianluigi

    2015-05-01

    PANDA is an experiment that will run at the future facility FAIR, Darmstadt, Germany. A high intensity and cooled antiproton beam will collide on a fixed hydrogen or nuclear target covering center-of-mass energies between 2.2 and 5.5 GeV. PANDA addresses various physics aspects from the low energy non-perturbative region towards the perturbative regime of QCD. With the impressive theoretical developments in this field, e.g. lattice QCD, the predictions are becoming more accurate in the course of time. The data harvest with PANDA will, therefore, be an ideal test bench with the aim to provide a deeper understanding of hadronic phenomena such as confinement and the generation of hadron masses. A variety of physics topics will be covered with PANDA, for example: the formation or production of exotic non-qqbar charm meson states connected to the recently observed XYZ spectrum; the study of gluon-rich matter, such as glueballs and hybrids; the spectroscopy of the excited states of strange and charm baryons, their production cross section and their spin correlations; the behaviour of hadrons in nuclear matter; the hypernuclear physics; the electromagnetic proton form factors in the timelike region. The PANDA experiment is designed to achieve the above mentioned physics goals with a setup with the following characteristics: an almost full solid angle acceptance; excellent tracking capabilities with high resolution (1-2 % at 1 GeV/c in the central region); secondary vertex detection with resolution ≈ 100 microns or better; electromagnetic calorimetry for detections of gammas and electrons up to 10 GeV; good particle identification of charge tracks (electrons, muons, pions, kaons, protons); a dedicated interchangeable central apparatus for the hypernuclear physics; detector and data acquisition system capable of working at 20 MHz interaction rate with an intelligent software trigger that can provide maximum flexibility.

  14. Antiproton and proton collisions with the alkali-metal atoms Li, Na, and K

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2008-01-01

    Single-electron ionization and excitation cross sections as well as cross sections for excitation into the first excited p state of the alkali-metal atoms Li(2s), Na(3s), and K(4s) colliding with antiprotons and protons were calculated using a time-dependent channel-coupling approach....... For antiprotons an impact-energy range from 0.25 to 1000 keV and for protons from 2 to 1000 keV was considered. The target atoms are treated as effective one-electron systems using a model potential. The results are compared with theoretical and experimental data from literature and calculated cross sections...

  15. Baryon fraction in the universe, antiproton lifetime, and the diffuse radiation

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, S.A. [Tata Institute of Fundamental Research, Homi Bhabha Road, Bombay 400005 (India); Finetti, N. [Particle Astrophysics Laboratory, New Mexico State University, Las Cruces, New Mexico 88003 (United States)

    1995-07-01

    We have calculated the diffuse spectrum in the energy region between 0.1 keV and 500 MeV, which arises from the decay of antiprotons in the baryon Symmetric Universe. Comparing this with the observation, we derived a life time of {gt}2.3{times}10 {sup 24} sec for the antiproton, which is 17 orders better than the one determined from laboratory experiments. We predict a cut-off in the diffuse radiation beyond 460 MeV, and if seen, would provide evidence for the existence of antimatter domains in the universe. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  16. Operating Procedure Changes to Improve Antiproton Production at the Fermilab Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Drendel, B.; Morgan, J.P.; Vander Meulen, D.; /Fermilab

    2009-04-01

    Since the start of Fermilab Collider Run II in 2001, the maximum weekly antiproton accumulation rate has increased from 400 x 10{sup 10} Pbars/week to approximately 3,700 x 10{sup 10} Pbars/week. There are many factors contributing to this increase, one of which involves changes to operational procedures that have streamlined and automated Antiproton Source production. Automation has been added to the beam line orbit control, stochastic cooling power level management, and RF settings. In addition, daily tuning efforts have been streamlined by implementing sequencer driven tuning software.

  17. Depth-Dose and LET Distributions of Antiproton Beams in Various Target Materials

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Olsen, Sune; Petersen, Jørgen B.B.;

    unrestricted LET is calculated for all configurations. Finally, we investigate which concentrations of gadolinium and boron are needed in a water target in order to observe a significant change in the antiproton depth-dose distribution.  Results Results indicate, that there is no significant change...... in the depth-dose distribution and average LET when substituting the materials. Adding boron and gadolinium up to concentrations of 1 per 1000 atoms to a water phantom, did not change the depth-dose profile nor the average LET. Conclusions  According to our FLUKA calculations, antiproton neutron capture...

  18. Pion, Kaon, Proton and Antiproton Production in Proton-Proton Collisions

    Science.gov (United States)

    Norbury, John W.; Blattnig, Steve R.

    2008-01-01

    Inclusive pion, kaon, proton, and antiproton production from proton-proton collisions is studied at a variety of proton energies. Various available parameterizations of Lorentz-invariant differential cross sections as a function of transverse momentum and rapidity are compared with experimental data. The Badhwar and Alper parameterizations are moderately satisfactory for charged pion production. The Badhwar parameterization provides the best fit for charged kaon production. For proton production, the Alper parameterization is best, and for antiproton production the Carey parameterization works best. However, no parameterization is able to fully account for all the data.

  19. Evidence for a Possible Proton-Antiproton Bound State from Lattice QCD

    CERN Document Server

    Loan, M

    2006-01-01

    We have used standard techniques of lattice quantum chromodynamics to look for evidence of the spin-zero six quark flavour singlet state ($J^{PC}=0^{-+}$) observed by BES Collaboration, and to determine the splitting between the mass of the possible proton-antiproton and the mass of two protons, its threshold. Ignoring quark loops and quark annihilation, we find indications that for sufficiently light quarks proton- antiproton is below the $2m_{p}$ threshold, making it a possible six-quark bound state.

  20. Production of a pion in association with a high-Q2 dilepton pair in antiproton-proton annihilation at GSI-FAIR

    CERN Document Server

    Lansberg, J P; Szymanowski, L

    2007-01-01

    We evaluate the cross section for anti-p p -> l+ l- pi0 in the forward direction and for large lepton pair invariant mass. In this kinematical region, the leading-twist amplitude factorises into a short-distance matrix element, long-distance dominated antiproton Distribution Amplitudes and proton to pion Transition Distribution Amplitudes (TDA). Using a modelling inspired from the chiral limit for these TDAs, we obtain a first estimate of this cross section, thus demonstrating that this process can be measured at GSI-FAIR.

  1. Study of Substructure of High Transverse Momentum Jets Produced in Proton-Antiproton Collisions at sqrt(s)=1.96 TeV

    CERN Document Server

    Aaltonen, T.

    2012-01-01

    A study of the substructure of jets with transverse momentum greater than 400 GeV/c produced in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider and recorded by the CDF II detector is presented. The distributions of the jet mass, angularity, and planar flow are measured for the first time in a sample with an integrated luminosity of 5.95 fb^-1. The observed substructure for high mass jets is consistent with predictions from perturbative quantum chromodynamics.

  2. Pion, Kaon and Antiproton Production in $Pb+Pb$ Collisions at LHC Energy $\\sqrt{s_{NN}}$ = 2.76 TeV : A Model-based Analysis

    CERN Document Server

    Guptaroy, P

    2014-01-01

    Large Hadron Collider (LHC) had produced a vast amount of high precision data for high energy heavy ion collision. We attempt here to study (i) transverse momenta spectra, (ii) $K/\\pi$, $p/\\pi$ ratio behaviours, (iii)rapidity distribution, and (iv) the nuclear modification factors of the pion, kaon and antiproton produced in $p+p$ and $Pb+Pb$ collisions at energy $\\sqrt{s_{NN}}$ = 2.76 TeV, on the basis of Sequential Chain Model (SCM). Comparisons of the model-based results with the measured data on these observables are generally found to be modestly satisfactory.

  3. Pectoral stretching program for women undergoing radiotherapy for breast cancer.

    Science.gov (United States)

    Lee, T S; Kilbreath, S L; Refshauge, K M; Pendlebury, S C; Beith, J M; Lee, M J

    2007-05-01

    Surgery and radiotherapy commonly cause adverse musculoskeletal problems, particularly loss of strength and range of motion, in the upper quadrant of breast cancer patients. Few well-designed studies have investigated whether these impairments can be prevented. Stretching is an effective technique for increasing range of motion, hence the aim of this study was to investigate whether a stretching program reduced acute musculoskeletal impairments in patients undergoing radiotherapy for breast cancer. Sixty-four women were recruited prior to commencement of radiotherapy following breast cancer surgery. Participants were randomised to either a control or stretch group. Participants in both groups were reviewed by the physical therapist on a weekly basis for approximately 6 weeks, and were given general information about skin care and lymphedema. The control group received no advice about exercise. The stretch group received instruction on low-load, prolonged pectoral stretches, which were to be performed daily and were checked at weekly visits. Shoulder range of motion, strength, arm circumference, and quality of life measurements were taken prior to, and at completion of radiotherapy, and at 7 months after radiotherapy. There was no difference in any outcome between groups. Breast symptoms increased for both groups during radiotherapy, without loss of strength or range of movement. The incidence of lymphedema during the study was low for both groups and did not differ between groups. The pectoral stretching program did not influence the outcomes measured because the symptoms reported by patients were not a consequence of contracture.

  4. Plan optimization for stereotactic radiotherapy

    NARCIS (Netherlands)

    J.A. de Pooter (Jacobus Abraham)

    2008-01-01

    textabstractCancer is one of the leading causes of death in the world. Next to surgery and chemotherapy, radiotherapy is one of the most used treatment modalities for cancer. About 50% of the patients with cancer will be treated with radiotherapy during the management of their disease. In radiothera

  5. The Confluence of Radiotherapy & Immunotherapy

    Directory of Open Access Journals (Sweden)

    Ralph Robert Weichselbaum

    2012-10-01

    Full Text Available Radiotherapy has been considered a local modality and outcomes have emphasized local and regional control of tumors. Recent data suggests that radiotherapy may activate the immune system and the combination of radiation therapy and immune therapies may have the potential to improve both local and distant control of tumor deposits. Below we review principals underlying the concepts of combining both modalities.

  6. Radiotherapy of benign diseases

    Energy Technology Data Exchange (ETDEWEB)

    Haase, W.

    1982-10-11

    Still today radiotherapy is of decisive relevance for several benign diseases. The following ones are briefly described in this introductory article: 1. Certain inflammatory and degenerative diseases as furuncles in the face, acute thrombophlebitis, recurrent pseudoriparous abscesses, degenerative skeletal diseases, cervical syndrome and others; 2. rheumatic joint diseases; 3. Bechterew's disease; 4. primary presenile osteoporosis; 5. syringomyelia; 6. endocrine ophthalmopathy; 7. hypertrophic processes of the connective tissue; 8. hemangiomas. A detailed discussion and a profit-risk analysis is provided in the individual chapters of the magazine.

  7. Collisions of low-energy antiprotons with molecular hydrogen: ionization, excitation and stopping power

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2009-01-01

    A time-dependent coupled-channel approach was used to calculate ionization, excitation, and energy-loss cross sections as well as energy spectra for antiproton and proton collisions with molecular hydrogen for impact energies 8 < E < 4000 keV....

  8. Relative Biological Effect of Antiprotons

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    nuclear research facility CERN. A beam of 126 MeV antiprotons, corresponding to about 12 cm range in water, was spread out to a SOBP with a width of 1 cm. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film, and the results were used for benchmarking...

  9. S142 set-up to detect X-ray from antiproton-proton atoms (protonium).

    CERN Multimedia

    1978-01-01

    This experiment was designed by the Daresbury-Mainz-TRIUMF Collaboration and was located in the m14 partially separated antiproton beam in the PS South Hall. It used a gaseous hydrogen target, 1 m long, surrounded by a ring of proportional counters, surrounded in turn by a ring of 36 scintillators strips to aid in the annihilation product identification. Ugo Gastaldi (centre)

  10. Antiproton-to-proton ratios for ALICE heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, A., E-mail: atawfik@cern.ch [Egyptian Center for Theoretical Physics (ECTP), MTI University, Cairo (Egypt)

    2011-06-01

    Assuming that the final state of hadronization takes place along the freezeout line, which is defined by a constant entropy density, the antiproton-to-proton ratios produced in heavy-ion collisions are studied in framework of the hadron resonance gas (HRG) model. A phase transition from quark-gluon plasma to hadrons, a hadronization, has been conjectured in order to allow modifications in the phase-space volume and thus in the single-particle distribution function. Implementing both modifications in the grand-canonical partition function and taking into account the experimental acceptance in the heavy-ion collisions, the antiproton-to-proton ratios over center-of-mass energies {radical}(s) ranging from AGS to RHIC are very well reproduced by the HRG model. Comparing with the same particle ratios in pp collisions results in a gradually narrowing discrepancy with increasing {radical}(s). At LHC energy, the ALICE antiproton-to-proton ratios in the pp collisions turn to be very well described by the HRG model as well. It is likely that the ALICE AA-program will produce the same antiproton-to-proton ratios as the pp-one. Furthermore, the ratio gets very close to unity indicating that the matter-antimatter asymmetry nearly vanishes. The chemical potential calculated at this energy strengthens the assumption of almost fully matter-antimatter symmetry up to the LHC energy.

  11. The Use of Creams in Radiotherapy

    DEFF Research Database (Denmark)

    Martinsen, May-Lin; Frost, Else; Bergmansen, Nina

    2015-01-01

    Purpose/Objective: At the Danish wards for radiotherapy there are different rules regarding the intervals that have to pass from the moment the patients applies moisturizer until they can be treated. This is due to the fact that it is unclear whether the cream can cause bolus effect, thereby...... causing the dose to move towards the skin. This would increase the damages to the patient’s skin during the radiotherapy. There is no evidence on the use of moisturizers. Materials and Methods: We have carried out an experimental trial testing whether creams cause bolus effect. We used two pieces of pork...... which we each divided into three squares in order to test our three preparations: Decubal Original Clinic Cream, Panthenol cream and Panthetonol ointment. All scans were carried out using a 64 slice Philips Brilliance Big Bore CT scanner. Conclusions: According to our results of the ml. measurements we...

  12. Breast cancer radiotherapy: controversies and prospectives

    Institute of Scientific and Technical Information of China (English)

    YU Jin-ming; WANG Yong-sheng

    2008-01-01

    @@ Despite consensus on breast cancer radiotherapy, there are still some controversies over post-mastectomy radiotherapy (PMRT) in patients with 1-3 positive lymph nodes, accelerated partial breast irradiation (APBI), appropriate sequence of radiotherapy, chemotherapy and hormonal treatment, and radiotherapy after preoperative systemic therapy.

  13. Development of dose audits for complex treatment techniques in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Stefanic, A. M.; Molina, L.; Vallejos, M.; Montano, G.; Zaretzky, A.; Saravi, M., E-mail: stefanic@cae.cnea.gov.ar [Centro Regional de Referencia con Patrones Secundarios para Dosimetria - CNEA, Presbitero Juan Gonzalez y Aragon 15, B1802AYA Ezeiza (Argentina)

    2014-08-15

    This work was performed in the frame of a Coordinated Research Project (CRP) with IAEA whose objective was to extend the scope of activities carried out by national TLD-based networks from dosimetry audit for rectangular radiation fields to irregular and small fields relevant to modern radiotherapy. External audit is a crucial element in QA programmes for clinical dosimetry in radiotherapy, therefore a methodology and procedures were developed and were made available for dose measurement of complex radiotherapy parameters used for cancer treatment. There were three audit steps involved in this CRP: TLD based dosimetry for irregular MLC fields for conformal radiotherapy, dosimetry in the presence of heterogeneities and 2D MLC shaped fields relevant to stereotactic radiotherapy and applicable to dosimetry for IMRT. In addition, a new development of film-based 2D dosimetry for testing dose distributions in small field geometry was included. The plan for each audit step involved a pilot study and a trial audit run with a few local hospitals. The pilot study focused on conducting and evaluation of the audit procedures with all participants. The trial audit run was the running of the audit procedures by the participants to test them with a few local radiotherapy hospitals. This work intends to provide audits which are much nearer clinical practice than previous audits as they involve significant testing of Tps methods, as well as verifications to determinate whether hospitals can correctly calculate dose delivery in radiation treatments. (author)

  14. AA magnet measurement team

    CERN Multimedia

    1978-01-01

    Quickly improvised measurement equipment for the AA (Antiproton Accumulator) was all the tight schedule permitted, but the high motivation of the team made up for the lack of convenience. From left to right: Roy Billinge (Joint AA Project Leader, the other one was Simon van der Meer); Bruno Autin, Brian Pincott, Colin Johnson.

  15. Report of the Snowmass T4 working group on particle sources: Positron sources, anti-proton sources and secondary beams

    Energy Technology Data Exchange (ETDEWEB)

    N. Mokhov et al.

    2002-12-05

    This report documents the activities of the Snowmass 2001 T4 Particle Sources Working Group. T4 was charged with examining the most challenging aspects of positron sources for linear colliders and antiproton sources for proton-antiproton colliders, and the secondary beams of interest to the physics community that will be available from the next generation of high-energy particle accelerators. The leading issues, limiting technologies, and most important R and D efforts of positron production, antiproton production, and secondary beams are discussed in this paper. A listing of T4 Presentations is included.

  16. Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p-Pb collisions at √{sNN} = 5.02 TeV

    Science.gov (United States)

    Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Almaraz, J. R. M.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arnaldi, R.; Arnold, O. W.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Balasubramanian, S.; Baldisseri, A.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Benacek, P.; 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.; Biro, G.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botta, E.; Bourjau, C.; 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.; Butt, J. B.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Ceballos Sanchez, C.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chauvin, A.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Cho, S.; 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.; Conesa Balbastre, G.; Conesa del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danisch, M. C.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; De Caro, A.; de Cataldo, G.; de Conti, C.; de Cuveland, J.; De Falco, A.; De Gruttola, D.; De Marco, N.; De Pasquale, S.; Deisting, A.; Deloff, A.; Dénes, E.; Deplano, C.; Dhankher, P.; Di Bari, D.; Di Mauro, A.; Di Nezza, P.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Endress, E.; Engel, H.; Epple, E.; Erazmus, B.; Erdemir, I.; Erhardt, F.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fronze, G. G.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Gauger, E. F.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; Gonzalez, V.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Grachov, O. A.; Graczykowski, L. K.; Graham, K. L.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Gronefeld, J. M.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hamon, J. C.; Harris, J. W.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hillemanns, H.; Hippolyte, B.; Horak, D.; Hosokawa, R.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Inaba, M.; Incani, E.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacazio, N.; Jacobs, P. M.; Jadhav, M. B.; Jadlovska, S.; Jadlovsky, J.; Jahnke, C.; Jakubowska, M. J.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Mohisin Khan, M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, D. W.; Kim, D. J.; Kim, D.; Kim, H.; Kim, J. S.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Klewin, S.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kostarakis, P.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Králik, I.; Kravčáková, A.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kuhn, C.; Kuijer, P. G.; Kumar, A.; Kumar, J.; Kumar, L.; Kumar, S.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Ladron de Guevara, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Lehas, F.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; León Vargas, H.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Lutz, T. H.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; Mcdonald, D.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Moreira De Godoy, D. A.; Moreno, L. A. P.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Munzer, R. H.; Murakami, H.; Murray, S.; Musa, L.; Musinsky, J.; Naik, B.; Nair, R.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Natal da Luz, H.; Nattrass, C.; Navarro, S. R.; Nayak, K.; Nayak, R.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira Da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pal, S. K.; Pan, J.; Pandey, A. K.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Pei, H.; Peitzmann, T.; Pereira Da Costa, H.; Peresunko, D.; Pérez Lara, C. E.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pimentel, L. O. D. L.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rami, F.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Read, K. F.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Šándor, L.; Sandoval, A.; Sano, M.; Sarkar, D.; Sarma, P.; Scapparone, E.; Scarlassara, F.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Šefčík, M.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Senyukov, S.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shahzad, M. I.; Shangaraev, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; de Souza, R. D.; Sozzi, F.; Spacek, M.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Stachel, J.; Stan, I.; Stankus, P.; Stefanek, G.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Suljic, M.; Sultanov, R.; Šumbera, M.; Szabo, A.; Szanto de Toledo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Tabassam, U.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tangaro, M. A.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trombetta, G.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Valencia Palomo, L.; Vallero, S.; Van Der Maarel, J.; Van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Villatoro Tello, A.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Weiser, D. F.; Wessels, J. P.; Westerhoff, U.; Whitehead, A. M.; Wiechula, J.; Wikne, J.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yang, H.; Yang, P.; Yano, S.; Yasin, Z.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yoon, J. H.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhang, C.; Zhang, Z.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.

    2016-09-01

    The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity (- 0.5 high transverse momentum (pT), the previously published pT spectra have been extended to include measurements up to 20 GeV/c for seven event multiplicity classes. The pT spectra for pp collisions at √{ s} = 7 TeV, needed to interpolate a pp reference spectrum, have also been extended up to 20 GeV/c to measure the nuclear modification factor (RpPb) in non-single diffractive p-Pb collisions. At intermediate transverse momentum (2 heavy-ion collisions. At high pT (> 10 GeV / c), the particle ratios are consistent with those reported for pp and Pb-Pb collisions at the LHC energies. At intermediate pT the (anti)proton RpPb shows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification. At high pT the charged pion, kaon and (anti)proton RpPb are consistent with unity within statistical and systematic uncertainties.

  17. Study of Interaction of Low-Energy Antiprotons with H$^{2}$,He$^{3}$,He$^{4}$,Ne-Nuclei Using a Streamer Chamber in Magnetic Field

    CERN Multimedia

    2002-01-01

    The aim of this experiment is the systematic study of the interaction between low-energy antiprotons and the H|2,~He|3,~He|4,~Ne-nuclei using a self shunted streamer chamber in a magnetic field exposed to the antiproton beam of the LEAR facility. The properties of the self shunted streamer chamber, which allows the use of the filling gas (hydrogen, helium, neon at a pressure of l~atm) as a target, permit to carry out experiments also in the very low-energy region. \\\\ \\\\ The experimental apparatus is suitable for a large programme of measurements. We plan to measure the @*H|2 cross section and the spectator momentum distributions at @* momenta lower than 250~MeV/c, where data are lacking. It is interesting to study for the first time the @*He|3 and @*He|4 interactions measuring the cross sections and the emitted particle distributions. Among other things the knowledge of the branching ratio of the @*He|4 annihilation channels clarifies some open cosmological questions. The study of the process of nuclear absor...

  18. Psychometric properties of the stress index radiooncology (SIRO) - a new questionnaire measuring quality of life of cancer patients during radiotherapy; Psychometrische Eigenschaften des Stress Index RadioOnkologie (SIRO) - ein neuer Fragebogen zur Erfassung der Lebensqualitaet bei Patienten unter Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Sehlen, S.; Fahmueller, H.; Lenk, M.; Duehmke, E. [Klinik und Poliklinik fuer Strahlentherapie, Ludwig-Maximilians-Univ., Klinikum Grosshadern, Muenchen (Germany); Herschbach, P. [Inst. und Poliklinik fuer Psychosomatische Medizin, Psychotherapie und Medizinische Psychologie, Technische Univ., Muenchen (Germany); Aydemir, U. [Inst. fuer Biometrie und Epidemiologie, Ludwig-Maximilians-Univ., Klinikum Grosshadern, Muenchen (Germany)

    2003-04-01

    Purpose: In the course of radiotherapy oncological patients often experience considerable psychosocial distress. For its measurement however, no specific questionnaire is available. The stress index radiooncology (SIRO), which is based upon the results of extensive preliminary studies, will be made available as a screening-instrument to facilitate measurement of psychosocial distress of cancer patients, including radiotherapy-induced distress. The aim of this study is, to psychometrically evaluate the preliminary version of the questionnaire, to transfer it to the final version (SIRO) and to gain information about the psychosocial distress of radiooncological patients at the beginning of radiotherapy. Patients and Methods: 104 cancer patients (18 to 85 years) with different diagnoses have been included in the study (Table 1). The data have been assessed by means of the preliminary version of the new questionnaire SIRO, the HADS, EORTC QLQ-C30 and LS. With 25 patients semistructured clinical interviews have been conducted. (orig.) [German] Hintergrund: Die strahlentherapeutische Behandlung von Tumorpatienten ist haeufig mit starken psychosozialen Belastungen verbunden, fuer deren Erfassung es bisher keinen spezifischen Fragebogen gibt. Mit dem stress index radioonkologie (SIRO), der auf den Analyseergebnissen umfangreicher Voruntersuchungen beruht, soll erstmals ein Screening-Instrument zur Verfuegung gestellt werden, mit dem die psychosozialen Belastungen von Tumorpatienten, einschliesslich der durch Strahlentherapie induzierten, erfasst werden koennen. Ziel dieser Studie ist, die Fragebogen-Vorform psychometrisch zu evaluieren und in die endgueltige Fragebogenversion (SIRO) zu ueberfuehren. Darueber hinaus sollen Informationen ueber das psychosoziale Belastungsprofil radioonkologischer Patienten zu Beginn einer Strahlentherapie gewonnen werden. Patienten und Methoden: 104 Tumorpatienten (18-85 Jahre) mit unterschiedlichen Diagnosen wurden in die Studie aufgenommen

  19. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  20. Evaluation of the contribution of contamination of radiotherapy room surfaces in the measure of exposure rate of radioiodine therapy patients; Avaliacao da contribuicao da contaminacao de superficies do quarto terapeutico na medida da taxa de exposicao de pacientes de radioiodoterapia

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Rafael Ferreira

    2015-07-01

    The contamination of radiotherapy room surfaces is significant and the measures of patient exposure rate are held on the fourth dependencies, relevant questions are raised: the background radiation of the room stay high due to surface contamination, may interfere with the rate of patient exposure at the time of its release? The monitoring site is important to determine whether the patient will be released? The value of the deal activity and the clinical condition of the patient may increase the contamination, influencing the monitoring results? This paper aims to conduct a quantitative analysis of surface contamination of the contribution of therapeutic room at the time is monitored exposure rate from inpatient. Measurements were made regarding the hospitalization of 32 patients with different doses administered activity, age and of both genders. The measurements were performed in the therapeutic rooms at the hospital Brotherhood Santa Casa de Misericordia de Sao Paulo. Exposure rate measurements were performed at the center of the room at 1 meter of the patient on the day of its release. After his release and prior to decontamination, measurements were performed at predetermined landmarks within the therapeutic room. The results revealed that on average background radiation, high due to surface contamination contributes only 2% of the patient dose rate. It can be considered that even with influence of contamination of surfaces, this is insignificant to determine if the patient may or may not be released. This study suggests that the site in which monitoring occurs exposure rate of the patient should not be decisive for liberation thereof. (author)

  1. Measurement of $\\beta(\\Lambda^{+}_{c} \\to pK^{-}\\pi^{+})$

    CERN Document Server

    Jaffe, D 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; 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; Baringer, P; Bean, A; Besson, D; Brabant, P; Cervantes, M; Kravchenko, I V; Stutz, R P; 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; Cronin-Hennessy, D; Kwon, Y; 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; Korolkov, I Ya; 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

    2000-01-01

    The /\\c->pKpi yield has been measured in a sample of two-jet continuum events containing a both an anticharm tag (Dbar) as well as an antiproton (e+e- -> Dbar pbar X), with the antiproton in the hemisphere opposite the Dbar. Under the hypothesis that such selection criteria tag e+e- -> Dbar pbar (/\\c) X events, the /\\c->pkpi branching fraction can be determined by measuring the pkpi yield in the same hemisphere as the antiprotons in our Dbar pbar X sample. Combining our results from three independent types of anticharm tags, we obtain B(/\\c->pKpi)=(5.0+/-0.5+/-1.2)%

  2. Stereotactic radiotherapy for vestibular schwannoma

    DEFF Research Database (Denmark)

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno;

    2014-01-01

    ; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014. SELECTION CRITERIA: Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical...

  3. The Charge Asymmetry In W Bosons Produced In Proton- Antiproton Collisions At Center Of Mass Energy = 1.96 Tev

    CERN Document Server

    Torborg, J

    2005-01-01

    The primary mode of production of W+ bosons in a pp¯ collider is u + d¯ → W+. The u quark generally carries more momentum than the d and the resultant W+ tends to be boosted in the proton direction. Similarly, W- bosons are boosted in the anti-proton direction. This is observed as an asymmetry in the rapidity distributions of positive and negative W bosons. Measurement of this asymmetry serves as a. probe of the momentum distribution of partons within the proton. These distributions are required as input to the calculation of every pp¯ production cross section. This thesis presents the first measurement at DØ of the charge asymmetry of the W boson production cross section as measured in W → eν decays in 0.3 fb-1 of pp¯ collisions collected with the DØ Detector. Theoretical predictions made using the CTEQ6.1M and MRST(2004) proton distribution functions are compared with the measurement.

  4. Radioprotectors in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nair, C.K.K. [Bhabha Atomic Research Centre, Mumbai (India); Parida, D.K.; Nomura, Taisei

    2001-03-01

    This review article focuses on clinically relevant radioprotectors and their mechanisms of radioprotection. Radiotherapy is the most common modality of human cancer therapy. Obtaining optimal results requires a judicious balance between the total dose of radiotherapy delivered and the threshold limit of critical surrounding normal tissues, and the normal tissues need to be protected against radiation injury to obtain better tumor control by using a higher dose. For this reason, radiation-protective agents play an important role in clinical radiotherapy. Radiation-protective agents can be classified into three groups: radioprotectors, adaptogens, and absorbents. The first group generally consists of sulfhydryl compounds and other antioxidants. They include several myelo-, entero-, and cerebro-protectors. Adaptogens act as promotors of radioresistance. They are natural protectors that offer chemical protection against low levels of ionizing radiation. Absorbents protect organs from internal radiation and chemicals. They include drugs that prevent incorporation of radioiodine by the thyroid gland and absorption of radionuclides. This article thoroughly describes the properties, mechanisms of action, and perspectives on clinical application of the following categories of radioprotectors: sulfhydryl compounds (e.g., cysteine, cysteamine, glutathione, AET, WR 2127, and other WR-compounds), antioxidants (e.g., tempace, Hoechst 33342, vitamin A, E, and C, TMG, melatonin), angiotensin-converting enzyme (ACE) inhibitors (e.g., captopril, elanopril, penicillamine, pentoxifylline, L-158, 809), cytoprotective agents (mesna, dexrazoxane, and amifostin), metalloelements (e.g., manganese chloride, cadmium salts, bismuth subnitrate), immunomodulators (gamma-interferon, polysaccharides AM5, AM218, heat-killed lactobacillus cells, broncho-vaxom, trehalose dicorynomycolate, and AS101), lipopolysaccharides and prostaglandins, plant extracts and compounds isolated from plants (curcmin

  5. "Discrepant hardenings" in cosmic ray spectra: a first estimate of the effects on secondary antiproton and diffuse gamma-ray yields

    CERN Document Server

    Donato, Fiorenza

    2010-01-01

    Recent data from CREAM seem to confirm early suggestions that primary cosmic ray spectra at few TeV/nucleon are harder than in the 10-100 GeV range. Also, helium and heavier nuclei spectra appear systematically harder than the proton fluxes at corresponding energies. We note here that if the measurements reflect intrinsic features in the interstellar fluxes, appreciable modifications are expected in the sub-TeV range for the secondary yields, such as antiprotons and diffuse gamma-rays. Presently, this effect represents a systematic error in the extraction of astrophysical parameters as well as for background estimates for indirect dark matter searches. We find that the spectral modifications are appreciable above 100 GeV, and can be responsible for ~30% effects for antiprotons at energies close to 1 TeV or for gamma's at energies close to 300 GeV, compared to currently considered predictions based on simple extrapolation of input fluxes from low energy data.

  6. Detector to detector corrections: a comprehensive experimental study of detector specific correction factors for beam output measurements for small radiotherapy beams

    DEFF Research Database (Denmark)

    Azangwe, Godfrey; Grochowska, Paulina; Georg, Dietmar

    2014-01-01

    -doped aluminium oxide (Al2O3:C), organic plastic scintillators, diamond detectors, liquid filled ion chamber, and a range of small volume air filled ionization chambers (volumes ranging from 0.002 cm3 to 0.3 cm3). All detector measurements were corrected for volume averaging effect and compared with dose ratios.......148 for the 0.14 cm3 air filled ionization chamber and were as high as 1.924 for the 0.3 cm3 ionization chamber. After applying volume averaging corrections, the detector readings were consistent among themselves and with alanine measurements for several small detectors but they differed for larger detectors......, in particular for some small ionization chambers with volumes larger than 0.1 cm3. Conclusions: The results demonstrate how important it is for the appropriate corrections to be applied to give consistent and accurate measurements for a range of detectors in small beam geometry. The results further demonstrate...

  7. Antihyperon potentials in nuclei via exclusive antiproton-nucleus reactions at FAIR

    CERN Document Server

    Lorente, Alicia Sanchez; Steinen, Marcell; Pochodzalla, Josef

    2015-01-01

    The exclusive production of hyperon-antihyperon pairs close to their production threshold in antiproton - nucleus collisions offers a unique and hitherto unexplored opportunity to elucidate the behaviour of antihyperons in nuclei. For the first time we analyse these reactions in a microscopic transport model using the the Gie\\ss en Boltzmann-Uehling-Uhlenbeck transport model. The calculation take the delicate interplay between the strong absorption of antihyperons, their rescattering and refraction at the nuclear surface as well as the Fermi motion of the struck nucleon into account. We find a substant