| Records |
| Author |
Bernabeu, J.; Martinez-Vidal, F. |
| Title |
Colloquium: Time-reversal violation with quantum-entangled B mesons |
Type |
Journal Article |
| Year |
2015 |
Publication |
Reviews of Modern Physics |
Abbreviated Journal |
Rev. Mod. Phys. |
| Volume |
87 |
Issue |
1 |
Pages |
165-182 |
Keywords  |
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| Abstract |
Symmetry transformations have been proven a bedrock tool for understanding the nature of particle interactions, formulating, and testing fundamental theories. Based on the up to now unbroken CPT symmetry, the violation of the CP symmetry between matter and antimatter by weak interactions, discovered in the decay of kaons in 1964 and observed more recently in 2001 in B mesons, strongly suggests that the behavior of these particles under weak interactions must also be asymmetric under time reversal T. However, until recent years there has not been a direct detection of the expected time-reversal violation in the time evolution of any system. This Colloquium examines the field of time-reversal symmetry breaking in the fundamental laws of physics. For transitions, its observation requires an asymmetry with exchange of initial and final states. A discussion is given of the conceptual basis for such an exchange with unstable particles, using the quantum properties of Einstein-Podolsky-Rosen entanglement available at B meson factories combined with the decay as a filtering measurement. The method allows a clear-cut separation of different transitions between flavor and CP eigenstates in the decay of neutral B mesons. These ideas have been implemented for the experiment by the BABAR Collaboration at SLAC's B factory. The results, presented in 2012, prove beyond any doubt the violation of time-reversal invariance in the time evolution between these two states of the neutral B meson. |
| Address |
[Bernabeu, J.; Martinez-Vidal, F.] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: Jose.Bernabeu@uv.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0034-6861 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000352076500001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
2179 |
| Permanent link to this record |
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| Author |
Cauchi, M.; Assmann, R.W.; Bertarelli, A.; Carra, F.; Cerutti, F.; Lari, L.; Redaelli, S.; Mollicone, P.; Sammut, N. |
| Title |
Thermomechanical response of Large Hadron Collider collimators to proton and ion beam impacts |
Type |
Journal Article |
| Year |
2015 |
Publication |
Physical Review Special Topics-Accelerators and Beams |
Abbreviated Journal |
Phys. Rev. Spec. Top.-Accel. Beams |
| Volume |
18 |
Issue |
4 |
Pages |
041002 - 14pp |
| Keywords |
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| Abstract |
The CERN Large Hadron Collider (LHC) is designed to accelerate and bring into collision high-energy protons as well as heavy ions. Accidents involving direct beam impacts on collimators can happen in both cases. The LHC collimation system is designed to handle the demanding requirements of high-intensity proton beams. Although proton beams have 100 times higher beam power than the nominal LHC lead ion beams, specific problems might arise in case of ion losses due to different particle-collimator interaction mechanisms when compared to protons. This paper investigates and compares direct ion and proton beam impacts on collimators, in particular tertiary collimators (TCTs), made of the tungsten heavy alloy INERMET (R) 180. Recent measurements of the mechanical behavior of this alloy under static and dynamic loading conditions at different temperatures have been done and used for realistic estimates of the collimator response to beam impact. Using these new measurements, a numerical finite element method (FEM) approach is presented in this paper. Sequential fast-transient thermostructural analyses are performed in the elastic-plastic domain in order to evaluate and compare the thermomechanical response of TCTs in case of critical beam load cases involving proton and heavy ion beam impacts. |
| Address |
[Cauchi, Marija; Assmann, R. W.; Bertarelli, A.; Carra, F.; Cerutti, F.; Lari, L.; Redaelli, S.] CERN, CH-1211 Geneva 23, Switzerland, Email: marija.cauchi@cern.ch |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1098-4402 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000352473800001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2180 |
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| Author |
Dias, J.M.; Aceti, F.; Oset, E. |
| Title |
Study of B<(B)over bar>* and B*<(B)over bar>* interactions in I=1 and relationship to the Z(b)(10610), Z(b)(10650) states |
Type |
Journal Article |
| Year |
2015 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
91 |
Issue |
7 |
Pages |
076001 - 14pp |
| Keywords |
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| Abstract |
We use the local hidden gauge approach in order to study the B (B) over bar* and B*(B) over bar* interactions for isospin I = 1. We show that both interactions via one light meson exchange are not allowed by the Okubo-ZweigIizuka rule and, for that reason, we calculate the contributions due to the exchange of two pions, interacting and noninteracting among themselves, and also due to the heavy vector mesons. Then, to compare all these contributions, we use the potential related to the heavy vector exchange as an effective potential corrected by a factor which takes into account the contribution of the other light meson exchanges. In order to look for poles, this effective potential is used as the kernel of the Bethe-Salpeter equation. As a result, for the B (B) over bar* interaction we find a loosely bound state with mass in the range 10587-10601 MeV, very close to the experimental value of the Z(b)(10610) reported by the Belle Collaboration. For the B*(B) over bar* case, we find a cusp at 10650 MeV for all spin J = 0, 1, 2 cases. |
| Address |
[Dias, J. M.; Aceti, F.; Oset, E.] Univ Valencia, Dept Fis Teor, Valencia 46071, Spain |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000352191000013 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2181 |
| Permanent link to this record |
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| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Measurement of B-c(+) Production in Proton-Proton Collisions at root s=8 TeV |
Type |
Journal Article |
| Year |
2015 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
114 |
Issue |
13 |
Pages |
132001 - 9pp |
| Keywords |
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| Abstract |
Production of B-c(+) mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of 2.0 fb(-1) recorded by the LHCb experiment. The ratio of production cross sections times branching fractions between the B_c. J/psi pi(+) and B+ -> J/psi K+ decays is measured as a function of transverse momentum and rapidity in the regions 0 < p(T) < 20 GeV/c and 2.0 < y < 4.5. The ratio in this kinematic range is measured to be (0.683 +/- 0.018 +/- 0.009)%, where the first uncertainty is statistical and the second systematic. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000352192600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2182 |
| Permanent link to this record |
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| Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
| Title |
Search for a light Higgs resonance in radiative decays of the Upsilon(1S) with a charm tag |
Type |
Journal Article |
| Year |
2015 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
91 |
Issue |
7 |
Pages |
071102 - 9pp |
| Keywords |
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| Abstract |
A search is presented for the decay Upsilon(1S) -> gamma A(0), A(0) -> c (c) over barc, where A(0) is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the Upsilon(2S) resonance. A sample of Upsilon(1S) mesons is selected via the decay Upsilon(2S) -> pi(+)pi(-)Upsilon(1S) . The A(0) -> c (c) over bar decay is identified through the reconstruction of hadronic D-0, D+,and D-0 (2010)(+) meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction beta(Upsilon(1S) -> gamma A(0)) x beta(A(0) -> (c) over barc range from 7.4 x 10(-5) to 2.4 x 10(-3) for A(0) masses from 4.00 to 8.95 GeV/c(2) and 9.10 to 9.25 GeV/c(2), where the region between 8.95 and 9.10 GeV/c(2) is excluded because of background from Upsilon(2S) -> gamma chi(bJ)(1P), chi(bJ)(1P) -> gamma Upsilon(1S) decays. |
| Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000352593400001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2188 |
| Permanent link to this record |
