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Author Bernabeu, J.; Segarra, A.
Title Do T asymmetries for neutrino oscillations in uniform matter have a CP-even component? Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages (up) 103 - 12pp
Keywords CP violation; Discrete Symmetries; Neutrino Physics
Abstract Observables of neutrino oscillations in matter have, in general, contributions from the effective matter potential. It contaminates the CP violation asymmetry adding a fake effect that has been recently disentangled from the genuine one by their different behavior under T and CPT. Is the genuine T-odd CPT-invariant component of the CP asymmetry coincident with the T asymmetry? Contrary to CP, matter effects in uniform matter cannot induce by themselves a non-vanishing T asymmetry; however, the question of the title remained open. We demonstrate that, in the presence of genuine CP violation, there is a new non-vanishing CP-even, and so CPT-odd, component in the T asymmetry in matter, which is of odd-parity in both the phase delta of the flavor mixing and the matter parameter a. The two disentangled components, genuine A(alpha beta)(T;CP) and fake A(alpha beta)(T;CPT), could be experimentally separated by the measurement of the two T asymmetries in matter (nu(alpha) <-> nu(beta)) and ((nu) over bar <-> (nu) over bar (beta)). For the (nu(mu) <-> nu(e)) transitions, the energy dependence of the new A(mu e)(T;CPT) component is like the matter-induced term A(mu e)(CP;CPT) of the CP asymmetry which is odd under a change of the neutrino mass hierarchy. We have thus completed the physics involved in all observable asymmetries in matter by means of their disentanglement into the three independent components, genuine A(alpha beta)(CP;T) and fake A(alpha beta)(CP;CPT) and A(alpha beta)(T;CPT).
Address [Bernabeu, Jose] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Valencia, Spain, Email: Jose.Bernabeu@uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000462327100001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3961
Permanent link to this record
 
 
Author Bernabeu, J.; Di Domenico, A.; Villanueva-Perez, P.
Title Probing CPT in transitions with entangled neutral kaons Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages (up) 139 - 19pp
Keywords Discrete and Finite Symmetries; Kaon Physics; CP violation
Abstract In this paper we present a novel CPT symmetry test in the neutral kaon system based, for the first time, on the direct comparison of the probabilities of a transition and its CPT reverse. The required interchange of in <-> out states for a given process is obtained exploiting the Einstein-Podolsky-Rosen correlations of neutral kaon pairs produced at a phi-factory. The observable quantities have been constructed by selecting the two semileptonic decays for flavour tag, the pi and 3 pi(0) decays for CP tag and the time orderings of the decay pairs. The interpretation in terms of the standard Weisskopf-Wigner approach to this system, directly connects CPT violation in these observables to the violating R delta parameter in the mass matrix of K-0 – (K) over bar (0), a genuine CPT violating effect independent of Delta Gamma and not requiring the decay as an essential ingredient. Possible spurious effects induced by CP violation in the decay and/or a violation of the Delta S = Delta Q rule have been shown to be well under control. The proposed test is thus fully robust, and might shed light on possible new CPT violating mechanisms, or further improve the precision of the present experimental limits. It could be implemented at the DA Phi NE facility in Frascati, where the KLOE-2 experiment might reach a statistical sensitivity of O (10(-3)) on the newly proposed observable quantities.
Address [Bernabeu, J.; Villanueva-Perez, P.] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: jose.bernabeu@uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000363478100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2420
Permanent link to this record
 
 
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 (up) 165-182
Keywords
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 Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-6861 ISBN Medium
Area Expedition Conference
Notes WOS:000352076500001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2179
Permanent link to this record
 
 
Author Benitez, V. et al; Bernabeu, J.; Garcia, C.; Lacasta, C.; Marco, R.; Rodriguez, D.; Santoyo, D.; Solaz, C.; Soldevila, U.
Title Sensors for the End-cap prototype of the Inner Tracker in the ATLAS Detector Upgrade Type Journal Article
Year 2016 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 833 Issue Pages (up) 226-232
Keywords Silicon radiation detectors; Strip sensors; HL-LHC; ATLAS Upgrade; Inner Tracker (ITk); End-cap
Abstract The new silicon microstrip sensors of the End-cap part of the HL-LHC ATLAS Inner Tracker (ITk) present a number of challenges due to their complex design features such as the multiple different sensor shapes, the varying strip pitch, or the built-In stereo angle. In order to investigate these specific problems, the “petalet” prototype was defined as a small End-cap prototype. The sensors for the petalet prototype include several new layout and technological solutions to investigate the issues, they have been tested in detail by the collaboration. The sensor description and detailed test results are presented in this paper. New software tools have been developed for the automatic layout generation of the complex designs. The sensors have been fabricated, characterized and delivered to the institutes in the collaboration for their assembly on petalet prototypes. This paper describes the lessons learnt from the design and tests of the new solutions implemented on these sensors, which are being used for the full petal sensor development. This has resulted in the ITIc strip, community acquiring the necessary expertise to develop the full End-cap structure, the petal.
Address [Benitez, V.; Ullan, M.; Quirion, D.; Pellegrini, G.; Fleta, C.; Lozano, M.] CSIC, CNM, IMB, Campus Univ Bellaterra, Barcelona 08193, Spain, Email: miguel.ullan@imb-cnm.csic.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000383818200032 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2816
Permanent link to this record
 
 
Author Aguilar-Saavedra, J.A.; Bernabeu, J.; Mitsou, V.A.; Segarra, A.
Title The Z boson spin observables as messengers of new physics Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 4 Pages (up) 234 - 6pp
Keywords
Abstract We demonstrate that the eight multipole parameters describing the spin state of the Z boson are able to disentangle known Z production mechanisms and signals from new physics at the LHC. They can be extracted from appropriate asymmetries in the angular distribution of lepton pairs from the Z boson decay. The power of this analysis is illustrated by (1) the production of Z boson plus jets; (2) Z boson plus missing transverse energy; (3) W and Z bosons originating from the two-body decay of a heavy resonance.
Address [Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: jaas@ugr.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000399448700004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3121
Permanent link to this record
 
 
Author Bernabeu, J.; Mavromatos, N.E.; Villanueva-Perez, P.
Title Consistent probabilistic description of the neutral Kaon system Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 724 Issue 4-5 Pages (up) 269-273
Keywords
Abstract The neutral Kaon system has both CF violation in the mass matrix and a non-vanishing lifetime difference in the width matrix. This leads to an effective Hamiltonian which is not a normal operator, with incompatible (non-commuting) masses and widths. In the Weisskopf-Wigner Approach (WWA), by diagonalizing the entire Hamiltonian, the unphysical non-orthogonal “stationary” states K-L,K-S are obtained. These states have complex eigenvalues whose real (imaginary) part does not coincide with the eigenvalues of the mass (width). matrix. In this work we describe the system as an open Lindblad-type quantum mechanical system due to Kaon decays. This approach, in terms of density matrices for initial and final states, provides a consistent probabilistic description, avoiding the standard problems because the width matrix becomes a composite operator not included in the Hamiltonian. We consider the dominant decay channel to two pions, so that one of the Kaon states with definite lifetime becomes stable. This new approach provides results for the time dependent decay rates in agreement with those of the WWA.
Address [Bernabeu, J.; Villanueva-Perez, P.] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: pablo.villanueva@uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000322358500011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1526
Permanent link to this record
 
 
Author Aguilar-Saavedra, J.A.; Bernabeu, J.
Title W polarisation beyond helicity fractions in top quark decays Type Journal Article
Year 2010 Publication Nuclear Physics B Abbreviated Journal Nucl. Phys. B
Volume 840 Issue 1-2 Pages (up) 349-378
Keywords
Abstract We calculate the density matrix for the decay of a polarised top quark into a polarised W boson and a massive 17 quark, for the most general Wth vertex arising from dimension-six gauge-invariant effective operators. We show that, in addition to the well-known W helicity fractions, for polarised top decays it is worth defining and studying the transverse and normal W polarisation fractions, that is, the W polarisation alone two directions orthogonal to its momentum. In particular, a rather simple forward-backward asymmetry in the normal direction is found to be very sensitive to complex phases in one of the Wth anomalous couplings. This asymmetry, which indicates a normal W polarisation, can be generated for example by a P-odd. T-odd transition electric dipole moment. We also investigate the angular distribution of decay products in the top quark rest frame, calculating the spin analysing powers for a general Wth vertex. Finally we show that, using a combined fit to top decay observables and the t W cross section, at LHC it will be possible to obtain model-independent measurements of all the (complex) Wth couplings as well as the single top polarisation. Implications for spin correlations in top pair production are also discussed.
Address [Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: jaas@ugr.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0550-3213 ISBN Medium
Area Expedition Conference
Notes ISI:000281832900013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 370
Permanent link to this record
 
 
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 (up) 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 Thesis
Publisher Annual Reviews Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-8998 ISBN Medium
Area Expedition Conference
Notes WOS:000363473100017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2430
Permanent link to this record
 
 
Author Bernabeu, J.
Title Discrete Symmetries CP,T,CPT Type Journal Article
Year 2016 Publication Acta Physica Polonica B Abbreviated Journal Acta Phys. Pol. B
Volume 47 Issue 2 Pages (up) 417-424
Keywords
Abstract The role of symmetry breaking mechanisms to search for new physics is of highest importance. We discuss the status and prospects of the discrete symmetries CP, T, CPT looking for their separate violation in LHC experiments and meson factories.
Address [Bernabeu, Jose] Univ Valencia, Dept Theoret Phys, E-46003 Valencia, Spain, Email: jose.bernabeu@uv.es
Corporate Author Thesis
Publisher Wydawnictwo Uniwersytetu Jagiellonskiego Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0587-4254 ISBN Medium
Area Expedition Conference
Notes WOS:000373493700022 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2628
Permanent link to this record
 
 
Author MoEDAL Collaboration (Acharya, B. et al); Bernabeu, J.; Garcia, C.; Mamuzic, J.; Mitsou, V.A.; Ruiz de Austri, R.; Santra, A.; Vento, V.; Vives, O.
Title Search for magnetic monopoles with the MoEDAL forward trapping detector in 2.11 fb(-1) of 13 TeV proton-proton collisions at the LHC Type Journal Article
Year 2018 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 782 Issue Pages (up) 510-516
Keywords
Abstract We update our previous search for trapped magnetic monopoles in LHC Run 2 using nearly six times more integrated luminosity and including additional models for the interpretation of the data. The MoEDAL forward trapping detector, comprising 222 kg of aluminium samples, was exposed to 2.11 fb(-1) of 13 TeV proton-proton collisions near the LHCb interaction point and analysed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges equal to the Dirac charge or above are excluded in all samples. The results are interpreted in Drell-Yan production models for monopoles with spins 0, 1/2 and 1: in addition to standard point-like couplings, we also consider couplings with momentum-dependent form factors. The search provides the best current laboratory constraints for monopoles with magnetic charges ranging from two to five times the Dirac charge.
Address [Acharya, B.; Alexandre, J.; Baines, S.; Ellis, J. R.; Fairbairn, M.; Mavromatos, N. E.; Sakellariadou, M.; Sarkar, S.] Kings Coll London, Dept Phys, Theoret Particle & Phys Cosmol Grp, London, England, Email: philippe.mermod@cern.ch
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000438486900076 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3664
Permanent link to this record