WorldWideScience

Sample records for antimesons

  1. How to test entanglement for meson-antimeson systems

    International Nuclear Information System (INIS)

    Bertlmann, R.A.; Durstberger, K.; Hiesmayr, B.C.

    2004-01-01

    Also in particle physics basic questions of quantum mechanics can be raised and the peculiar behavior of entanglement can be investigated, which is the basic ingredient for the future technologies such as quantum information and quantum communication. A Bell inequality - analogous to the entangled photon system - can be derived, however, the inequality is not violated because of the 'unfortunate' constants in these systems. However, these entangled meson-antimeson systems offer other properties - not analogous to other known spin-1/2 systems - which open new insights, e.g. that the violation of the CP symmetry is related to entanglement. Another approach to study entanglement is via decoherence models. New data from the B-meson factory of the KEKB collider in Japan (BELLE detector) or the new data from the K-meson factory of the DAPHNE machine in Italy can be used to get upper bounds on decoherence and to test/exclude different decoherence models. Surprisingly, it turns out that the parameter extracted from the experiments is in simple connections to mathematical and theoretical concepts which in this way are directly confronted with experimental data. (author)

  2. On unitarity relations and their application to meson–antimeson mixing

    Indian Academy of Sciences (India)

    Abstract. In view of the recent observation of nonexponential decay features for a certain quantum- mechanical system, we revisit our earlier study of the small-time behaviour of the meson–antimeson complex wherein the commonly employed Weisskopf–Wigner approximation could be tested, in principle. We find that the ...

  3. Equality of e+e- production amplitudes for scalar-vector and pseudoscalar-axial heavy meson-antimeson pairs

    Science.gov (United States)

    Voloshin, M. B.

    2018-02-01

    The production of heavy meson-antimeson pairs of the type S V and P A in e+e- annihilation is considered, with P and V being the ground-state JP=0- and JP=1- (anti)mesons from the (1 /2 )-doublet and S and A standing for the excited JP=0+ and JP=1+ (anti)mesons from the (1 /2 )+doublet. It is argued that the production amplitudes in these two channels should be equal up to a higher (than one) order in the heavy quark mass (ΛQCD/MQ ) expansion, A (e +e-→S V ¯ )=A (e+e-→A P ¯ ) , including both the S -wave and the D -wave amplitudes. Given that the S V and P A thresholds are extremely close, the production cross section in both channels should be the same to a high degree of accuracy. In practice, this behavior can be studied for the processes e+e-→Ds 0(2317 )D¯s *+c .c . and e+e-→Ds 1(2460 )D¯ s+c .c . in the charm sector and e+e-→Bs 0B¯s *+c .c . and e+e-→Bs 1B¯ s+c .c . in the B sector.

  4. On unitarity relations and their application to meson–antimeson mixing

    Indian Academy of Sciences (India)

    and N ¯f f. : it is important to consider at least one more (say, B5) two-time asymmetry, and not crucial to consider the remaining three (B. 6 7 8) for which all the relevant features are qualitatively the same as for the B5 case. Our study of the new asymmetries B j confirms the need to investigate nonleading terms.

  5. Heavy Quark Symmetries: Molecular partners of the X(3872 and Zb(10610/Zb′(10650

    Directory of Open Access Journals (Sweden)

    Guo Feng-Kun

    2014-06-01

    Full Text Available In this work, we have made use of the identification of the X(3872 and Zb(10610/Zb′(10650 as heavy meson-heavy antimeson molecules to establish some consequences derived from the symmetries that these heavy meson-heavy antimeson systems must have. We show the most general effective lagrangian that respects these symmetries only depends on four undetermined low energy constants (LECs, which will be fitted to reproduce the experimental data about the resonances we are identifying as molecular states. Then, we obtain a whole new set of states in the spectrum that could also be thought as heavy meson-heavy antimeson molecules. Finally, using another different symmetry: Heavy Antiquark-Diquark Symmetry, we can also establish a set of pentaquark-like states taking advantage of the previous LEC calculation.

  6. The fact of the matter the first results of an experiment designed to find out why the universe is composed of matter have just been announced

    CERN Multimedia

    2001-01-01

    The PEP accelerator at SLAC was relaunched as a B-Factory in May 1999. It has just published its first results which do show the predicted asymmetry in the behaviour of B-mesons and anti-mesons. This is not enough however to account for all the matter in the universe (1 page).

  7. Non-locality versus entanglement in the neutral kaon system

    International Nuclear Information System (INIS)

    Ableitinger, A.; Bertlmann, R.A.; Durstberger, K.; Hiesmayr, B.C.; Krammer, P.

    2006-01-01

    Full text: Particle physics has become an interesting testing ground for fundamental questions of quantum mechanics (QM). The entangled massive meson-antimeson systems are specially suitable as they offer a unique laboratory to test various aspects of particle physics (CP violation, CPT violation, . . . ) as well to test foundations of QM (local realistic theories versus QM, Bell inequalities, decoherence effects, quantum marking and erasure concepts, . . . ). For the neutral kaon system we show that nonlocality detected by the violation of a Bell inequality and entanglement are indeed different concepts. (author)

  8. Revealing Bell's nonlocality for unstable systems in high energy physics

    International Nuclear Information System (INIS)

    Hiesmayr, Beatrix C.; Gabriel, Andreas; Huber, Marcus; Di Domenico, Antonio; Curceanu, Catalina; Larsson, Jan-Aake; Moskal, Pawel

    2012-01-01

    Entanglement and its consequences - in particular the violation of Bell inequalities, which defies our concepts of realism and locality - have been proven to play key roles in Nature by many experiments for various quantum systems. Entanglement can also be found in systems not consisting of ordinary matter and light, i.e. in massive meson-antimeson systems. Bell inequalities have been discussed for these systems, but up to date no direct experimental test to conclusively exclude local realism was found. This mainly stems from the fact that one only has access to a restricted class of observables and that these systems are also decaying. In this Letter we put forward a Bell inequality for unstable systems which can be tested at accelerator facilities with current technology. Herewith, the long awaited proof that such systems at different energy scales can reveal the sophisticated ''dynamical'' nonlocal feature of Nature in a direct experiment gets feasible. Moreover, the role of entanglement and CP violation, an asymmetry between matter and antimatter, is explored, a special feature offered only by these meson-antimeson systems. (orig.)

  9. B decay anomalies and dark matter from vectorlike confinement

    Science.gov (United States)

    Cline, James M.

    2018-01-01

    Lepton flavor universality violating B →K ℓℓ and K*ℓℓ decays tentatively observed by LHCb can be explained by leptoquark exchange. We explore a simple model for the B anomalies with a composite leptoquark from new strong dynamics at the TeV scale, a confining SU(NH C) hypercolor interaction. The new matter fields, fundamentals under SU (NH C) , are heavy vectorlike fermions Ψ , S , and an inert scalar doublet ϕ . Ψ is colored under QCD while S is neutral, and the hyperbaryon SN is an asymmetric dark matter candidate. The model is tightly constrained by meson-antimeson oscillations, lepton flavor violation, and LHC searches for resonant production of the exotic bound states. The dark matter may be detectable through its magnetic dipole moment. If mS is sufficiently small, composite leptoquarks and heavy lepton partners can be pair-produced at an observable level at LHC.

  10. A lattice QCD determination of potentials between pairs of static-light mesons

    Energy Technology Data Exchange (ETDEWEB)

    Hetzenegger, Martin

    2011-07-04

    Potentials between pairs of static-light mesons are interesting in a sense that they give insights in the nature of strong interactions from first principles for multiquark systems. For large heavy quark masses, e.g., the spectra of heavy-light mesons are determined by excitations of the light quark and gluonic degrees of freedom. In particular, the vector-pseudoscalar splitting vanishes and a static-light meson can be interpreted as either a B, a B{sup *}, a D or a D{sup *} heavy-light meson. Calculating potentials between two static-light mesons also enables investigations of possible bound tetraquark states or for particles that are close to the meson-antimeson threshold, such as the X(3872) or the Z{sup +}(4430).

  11. A lattice QCD determination of potentials between pairs of static-light mesons

    International Nuclear Information System (INIS)

    Hetzenegger, Martin

    2011-01-01

    Potentials between pairs of static-light mesons are interesting in a sense that they give insights in the nature of strong interactions from first principles for multiquark systems. For large heavy quark masses, e.g., the spectra of heavy-light mesons are determined by excitations of the light quark and gluonic degrees of freedom. In particular, the vector-pseudoscalar splitting vanishes and a static-light meson can be interpreted as either a B, a B * , a D or a D * heavy-light meson. Calculating potentials between two static-light mesons also enables investigations of possible bound tetraquark states or for particles that are close to the meson-antimeson threshold, such as the X(3872) or the Z + (4430).

  12. Open-channel effects on heavy-quarkonium spectra: a phenomenological study within a one-open-channel approximation

    International Nuclear Information System (INIS)

    Matsuda, Y.; Kato, K.; Yabusaki, N.; Hirano, M.; Nakanishi, R.; Sakai, M.

    1997-01-01

    Open-channel effects on charmonium (S- and D-waves) and bottomonium (S-wave) J P = 1 - spectra are investigated within a one-open-channel approximation. Mass shifts and decay widths of these states just above the threshold are obtained by taking into account a coupling between confined quarkonium states and decaying states of the open channel. The final-state interaction (FSI) between the decaying meson and antimeson plays a very important role in producing a reasonable magnitude of coupling; the FSI provides the open-channel poles (R 1 , R 2 ) at the appropriate positions on the complex energy plane. The result is found to be independent of the detailed form of the transition potential and the final-state interaction. (author)

  13. Semialigned two Higgs doublet model

    Science.gov (United States)

    Haba, Naoyuki; Umeeda, Hiroyuki; Yamada, Toshifumi

    2018-02-01

    In the left-right symmetric model based on S U (2 )L×S U (2 )R×U (1 )B -L gauge symmetry, there appear heavy neutral scalar particles mediating quark flavor changing neutral currents (FCNCs) at tree level. We consider a situation where such FCNCs give the only sign of the left-right model while WR gauge boson is decoupled, and name it "semialigned two Higgs doublet model" because the model resembles a two Higgs doublet model with mildly aligned Yukawa couplings to quarks. We predict a correlation among processes induced by quark FCNCs in the model, and argue that future precise calculation of meson-antimeson mixings and C P violation therein may hint at the semialigned two Higgs doublet model and the left-right model behind it.

  14. Observation of charm mixing at LHCb

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Meson-antimeson mixing has been observed in the K0−K0bar, B0−B0bar and B0s−B0sbar systems. Evidence of mixing in the charm system has been reported by three experiments using different D0 decay channels, but only the combination of these results provides confirmation of D0−D0bar mixing with more than 5σ significance. We report a measurement of charm mixing using the time-dependent ratio of D0 → K+π− to D0 → K−π+ decay rates in D∗+-tagged events reconstructed in 1.0 fb−1 of integrated luminosity recorded by the LHCb experiment in 2011. We measure the mixing parameters x'2 = (−0.9 ± 1.3) × 10−4, y' = (7.2 ± 2.4) × 10−3 and the ratio of doubly-Cabibbo-suppressed to Cabibbo-favored decay rates RD = (3.52 ± 0.15) × 10−3. The result excludes the no-mixing hypothesis with a probability corresponding to 9.1σ and represents the first observation of D0−D0bar oscillations from a single measurement.

  15. 54. Annual symposium of the Austrian Physical Society

    International Nuclear Information System (INIS)

    Lippitsch, M.

    2004-01-01

    The papers presented were organized under the following sessions: main session (from attoseconds to RGB to telecom, density functional calculations, magnetic anisotropy of nanostructures, quantum cascade laser, bose-einstein condensates, DNA molecular force sensor); Fritz-Kohlrausch-price 2004 (nanoscale building blocks), Max-Auwaerter-price 2004 (electron emission and nano defects, magnetic rings), AT + S price 2004 (conducting atomic-force microscopy for nanoscale studies), Viktor-Hess-price 2004 (entanglement for meson-antimeson systems), Roman-Ulrich-Sexl-price 2004 (teaching physics ); acoustics; atomic-, molecular- and plasma physics (kinetic electron emission, accelerated-mass spectrometry of molecules, dissociative electron attachment, voc measurements); solid physics (spin relaxation, nano clean room reactor, proton transport through nanotubes); nuclear and particle physics (color reconnection, supersymmetry at Large Hadron Collider, pionic hydrogen, kaonic hydrogen, quantum chaos, quantum dwell time, trigger system simulation, ATLAS initial detector layout, QCD); medical-, bio-and environmental physics (PTR-MS, validation Monte Carlo FLUKA codes, Gamma camera- positron emission tomography); neutrons and synchrotron radiation physics (3D synchrotron micro on human bones); surface and thin film analysis; quantum electronics, electrodynamics and optics (teleportation, optic induced changes in interaction in BEC, electronic feed back cooling single ions) and poster sessions with topics dealing with the subjects above mentioned. This book of abstracts contains their summaries and those contributions which are in the INIS subject scope are indexed individually. (nevyjel)

  16. The custodially protected Randall-Sundrum model. Theoretical aspects and flavour phenomenology

    International Nuclear Information System (INIS)

    Blanke, Monika

    2009-01-01

    Models with a warped extra dimension, so-called Randall-Sundrum models, provide an appealing solution to the gauge and flavour hierarchy problems of the Standard Model. After introducing the theoretical basics of such models, we concentrate on a specific model whose symmetry structure is extended to protect the T parameter and the Zb L anti b L coupling from large corrections. We introduce the basic action and discuss in detail effects of electroweak symmetry breaking and the flavour structure of the model. Then we analyse meson-antimeson mixing and rare decays that are affected by new tree level contributions from the Kaluza-Klein modes of the gauge bosons and from the Z boson in an important manner. After deriving analytic expressions for the most important K and B physics observables, we perform a global numerical analysis of the new effects in the model in question. We confirm the recent findings that a stringent constraint on the model is placed by CP-violation in K 0 - anti K 0 mixing. However, even for Kaluza-Klein particles in the reach of the LHC an agreement with all available data can be obtained without significant fine-tuning. We find possible large effects in either CP-violating effects in the B s - anti B s system or in the rare K decays, but not simultaneously. In any case the deviations from the Standard Model predictions in the rare B decays are small and difficult to measure. The specific pattern of new flavour effects allows to distinguish this model from other New Physics frameworks, which we demonstrate explicitly for the case of models with Minimal Flavour Violation and for the Littlest Higgs model with T-parity. (orig.)

  17. The custodially protected Randall-Sundrum model. Theoretical aspects and flavour phenomenology

    Energy Technology Data Exchange (ETDEWEB)

    Blanke, Monika

    2009-07-24

    Models with a warped extra dimension, so-called Randall-Sundrum models, provide an appealing solution to the gauge and flavour hierarchy problems of the Standard Model. After introducing the theoretical basics of such models, we concentrate on a specific model whose symmetry structure is extended to protect the T parameter and the Zb{sub L} anti b{sub L} coupling from large corrections. We introduce the basic action and discuss in detail effects of electroweak symmetry breaking and the flavour structure of the model. Then we analyse meson-antimeson mixing and rare decays that are affected by new tree level contributions from the Kaluza-Klein modes of the gauge bosons and from the Z boson in an important manner. After deriving analytic expressions for the most important K and B physics observables, we perform a global numerical analysis of the new effects in the model in question. We confirm the recent findings that a stringent constraint on the model is placed by CP-violation in K{sup 0} - anti K{sup 0} mixing. However, even for Kaluza-Klein particles in the reach of the LHC an agreement with all available data can be obtained without significant fine-tuning. We find possible large effects in either CP-violating effects in the B{sub s} - anti B{sub s} system or in the rare K decays, but not simultaneously. In any case the deviations from the Standard Model predictions in the rare B decays are small and difficult to measure. The specific pattern of new flavour effects allows to distinguish this model from other New Physics frameworks, which we demonstrate explicitly for the case of models with Minimal Flavour Violation and for the Littlest Higgs model with T-parity. (orig.)

  18. Two approaches towards the flavour puzzle. Dynamical minimal flavour violation and warped extra dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, Michaela E.

    2010-08-16

    out the flavour and electroweak (EW) sector, including a derivation of Feynman rules. Moreover, we determine the contributions to the effective Hamiltonian for meson-antimeson mixing due to KK gluon and KK photon exchange. (orig.)