Records |
Author |
Kittel, O.; Pilaftsis, A. |
Title |
CP violation in correlated production and decay of unstable particles |
Type |
Journal Article |
Year |
2012 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
Volume |
856 |
Issue |
3 |
Pages |
682-697 |
Keywords |
EPR correlation; Resonant CP violation; Collider phenomenology |
Abstract |
We study resonant CP-violating Einstein-Podolsky-Rosen correlations that may take place in the production and decay of unstable scalar particles at high-energy colliders. We show that as a consequence of unitarity and CPT invariance of the S-matrix, in 2 -> 2 scatterings mediated by mixed scalar particles, at least three linearly independent decay matrices associated with the unstable scalar states are needed to obtain non-zero CP-odd observables that are also odd under C-conjugation. Instead, for the correlated production and decay of two unstable particle systems in 2 -> 4 processes, we find that only two independent decay matrices are sufficient to induce a net non-vanishing CP-violating phenomenon. As an application of this theorem, we present numerical estimates of CP asymmetries for the correlated production and decay of supersymmetric scalar top anti-top pairs at the LHC, and demonstrate that these could reach values of order one. As a byproduct of our analysis, we develop a novel spinorial trace technique, which enables us to efficiently evaluate lengthy expressions of squared amplitudes describing the resonant scalar transitions. |
Address |
[Kittel, Olaf] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: kittel@th.physik.uni-bonn.de |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0550-3213 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000300028200004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
892 |
Permanent link to this record |
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Author |
KLOE-2 Collaboration (Babusci, D. et al); Bernabeu, J. |
Title |
Direct tests of T, CP, CPT symmetries in transitions of neutral K mesons with the KLOE experiment |
Type |
Journal Article |
Year |
2023 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
845 |
Issue |
|
Pages |
138164 - 11pp |
Keywords |
Discrete and finite symmetries; Kaon physics; CP violation |
Abstract |
Tests of the T, CP and CPT symmetries in the neutral kaon system are performed by the direct comparison of the probabilities of a kaon transition process to its symmetry-conjugate. The exchange of in and out states required for a genuine test involving an antiunitary transformation implied by time-reversal is implemented exploiting the entanglement of K0K0 pairs produced at a 0 -factory.A data sample collected by the KLOE experiment at DAONE corresponding to an integrated luminosity of about 1.7 fb-1 is analysed to study the At distributions of the 0 -> KSKL -> pi+pi- pi +/- e -/+ v and 0 -> KSKL -> pi +/- e -/+ v3 pi 0 processes, with At the difference of the kaon decay times. A comparison of the measured At distributions in the asymptotic region At ⠅ iS allows to test for the first time T and CPT symmetries in kaon transitions with a precision of few percent, and to observe CP violation with this novel method. |
Address |
[Mandaglio, G.] INFN, Sez Catania, Catania, Italy, Email: eryk.czerwinski@uj.edu.pl |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:001080223500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5704 |
Permanent link to this record |
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Author |
Gisbert, H.; Pich, A. |
Title |
Direct CP violation in K-0 -> pi pi : Standard Model Status |
Type |
Journal Article |
Year |
2018 |
Publication |
Reports on Progress in Physics |
Abbreviated Journal |
Rep. Prog. Phys. |
Volume |
81 |
Issue |
7 |
Pages |
076201 - 22pp |
Keywords |
Kaon decays; CP violation; Standard Model |
Abstract |
In 1988 the NA31 experiment presented the first evidence of direct CP violation in the K-0 -> pi pi decay amplitudes. A clear signal with a 7.2 sigma statistical significance was later established with the full data samples from the NA31, E731, NA48 and KTeV experiments, confirming that CP violation is associated with a Delta S = 1 quark transition, as predicted by the Standard Model. However, the theoretical prediction for the measured ratio epsilon'/epsilon has been a subject of strong controversy along the years. Although the underlying physics was already clarified in 2001, the recent release of improved lattice data has revived again the theoretical debate. We review the current status, discussing in detail the different ingredients that enter into the calculation of this observable and the reasons why seemingly contradictory predictions were obtained in the past by several groups. An update of the Standard Model prediction is presented and the prospects for future improvements are analysed. Taking into account all known short-distance and long-distance contributions, one obtains Re (epsilon' / epsilon) = (15 +/- 7) . 10(-4), in good agreement with the experimental measurement. |
Address |
[Gisbert, Hector; Pich, Antonio] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apt Correus 22085, E-46071 Valencia, Spain, Email: Antonio.Pich@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
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 |
0034-4885 |
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:000436545600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3641 |
Permanent link to this record |
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Author |
Bernabeu, J.; Martinez-Vidal, F. |
Title |
Time-Reversal Violation |
Type |
|
Year |
2015 |
Publication |
Annual Review of Nuclear and Particle Science |
Abbreviated Journal |
Annu. Rev. Nucl. Part. Sci. |
Volume |
65 |
Issue |
|
Pages |
403-427 |
Keywords |
time reversal; CP violation; T-odd products; electric dipole moments; B mesons; K mesons; EPR entanglement |
Abstract |
The violation of CP symmetry between matter and antimatter in the neutral K and B meson systems is well established, with a high degree of consistency between all available experimental measurements and with the Standard Model of particle physics. On the basis of the up-to-now-unbroken CPT symmetry, the violation of CP symmetry strongly suggests that the behavior of these particles under weak interactions must also be asymmetric under time reversal T. Many searches for T violation have been performed and proposed using different observables and experimental approaches. These include T-odd observables, such as triple products in weak decays, and genuine observables, such as permanent electric dipole moments of nondegenerate stationary states and the breaking of the reciprocity relation. We discuss the conceptual basis of the required exchange of initial and final states with unstable particles, using quantum entanglement and the decay as a filtering measurement, for the case of neutral B and K mesons. Using this method, the BaBar experiment at SLAC has clearly observed T violation in B mesons. |
Address |
[Bernabeu, Jose; Martinez-Vidal, Fernando] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain |
Corporate Author |
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Thesis |
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Publisher |
Annual Reviews |
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 |
0163-8998 |
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:000363473100017 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2430 |
Permanent link to this record |
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Author |
T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Fernandez, P.; Izmaylov, A.; Novella, P. |
Title |
Search for neutral-current induced single photon production at the ND280 near detector in T2K |
Type |
Journal Article |
Year |
2019 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
Volume |
46 |
Issue |
8 |
Pages |
08LT01 - 16pp |
Keywords |
T2K; neutrino; neutrino oscillation; neutrino interaction; Mini-BooNE; CP violation |
Abstract |
Neutrino neutral-current (NC) induced single photon production is a sub-leading order process for accelerator-based neutrino beam experiments including T2K. It is, however, an important process to understand because it is a background for electron (anti)neutrino appearance oscillation experiments. Here, we performed the first search of this process below 1 GeV using the fine-grained detector at the T2K ND280 off-axis near detector. By reconstructing single photon kinematics from electron-positron pairs, we achieved 95% pure gamma ray sample from 5.738 x 10(20) protons-on-targets neutrino mode data. We do not find positive evidence of NC induced single photon production in this sample. We set the model-dependent upper limit on the cross-section for this process, at 0.114 x 10(-38) cm(2) (90% C.L.) per nucleon, using the J-PARC off-axis neutrino beam with an average energy of < E-v > similar to 0.6 GeV. This is the first limit on this process below 1 GeV which is important for current and future oscillation experiments looking for electron neutrino appearance oscillation signals. |
Address |
[Berguno, D. Bravo; Ishii, T.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid, Spain |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
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 |
0954-3899 |
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:000518888100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4318 |
Permanent link to this record |