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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 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 (down) 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
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Author Bernabeu, J.; Botella, F.J.; Nebot, M.
Title Novel T-Violation observable open to any pair of decay channels at meson factories Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 728 Issue Pages 95-98
Keywords
Abstract Quantum entanglement between the two neutral mesons produced in meson factories has allowed the first indisputable direct observation of Time Reversal Violation in the time evolution of the neutral meson between the two decays. The exceptional meson transitions are directly connected to semileptonic and CP eigenstate decay channels. The possibility of extending the observable asymmetries to more decay channels confronts the problem of the “orthogonality condition”, which can be stated with this tonguetwister: Given a decay channel f, which is the decay channel f' such that the meson state not decaying to f is orthogonal to the meson state not decaying to f? In this Letter we propose an alternative T-Violation asymmetry at meson factories which allows its opening to any pair of decay channels. Instead of searching which is the pair of decay channels associated to the T-reverse meson transition, we build an asymmetry which tags the initial states of both the Reference and the T-reverse meson transitions. This observable filters the appropriate final states by means of two measurable survival probabilities. We discuss the methodology to be followed in the analysis of the new observable and the results expected in specific examples.
Address [Nebot, Miguel] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@uv.es;
Corporate Author Thesis
Publisher (down) 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:000330556000017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1705
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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 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 (down) 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
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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 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 (down) 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
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Author Helling, C. et al; Bernabeu, J.; Lacasta, C.; Solaz, C.
Title Strip sensor performance in prototype modules built for ATLAS ITk Type Journal Article
Year 2020 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 978 Issue Pages 164402 - 6pp
Keywords Silicon strip sensors; Strip module; Inter-strip isolation; Readout noise
Abstract ATLAS experiment is preparing an upgrade of its detector for High-Luminosity LHC (HL-LHC) operation. The upgrade involves installation of the new all-silicon Inner Tracker (ITk). In the context of the ITk preparations, more than 80 strip modules were built with prototype barrel sensors. They were tested with electrical readout on a per-channel basis. In general, an excellent performance was observed, consistent with previous ASIC-level and sensor-level tests. However, the lessons learned included two phenomena important for the future phases of the project. First was the need to store and test the modules in a dry environment due to humidity sensitivity of the sensors. The second was an observation of high noise regions for 2 modules. The high noise regions were tested further in several ways, including monitoring the performance as a function of time and bias voltage. Additionally, direct sensor-level tests were performed on the affected channels. The inter-strip resistance and bias resistance tests showed low values, indicating a temporary loss of the inter-strip isolation. A subsequent recovery of the noise performance was observed. We present the test details, an analysis of how the inter-strip isolation affects the module noise, and the relationship with sensor-level quality control tests.
Address [Helling, C.; Affolder, A. A.; Fadeyev, V.; Galloway, Z.; Gignac, M.; Gunnell, J.; Martinez-Mckinney, F.; Kang, N.; Yarwick, J.] Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA, Email: fadeyev@ucsc.edu
Corporate Author Thesis
Publisher (down) Elsevier 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:000560076700015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4505
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Author Latonova, V. et al; Bernabeu, J.; Lacasta, C.; Solaz, C.; Soldevila, U.
Title Characterization of the polysilicon resistor in silicon strip sensors for ATLAS inner tracker as a function of temperature, pre- and post-irradiation Type Journal Article
Year 2023 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1050 Issue Pages 168119 - 5pp
Keywords HL-LHC; ATLAS ITk; Silicon micro-strip sensor; Polysilicon bias resistor; Testchip
Abstract The high luminosity upgrade of the Large Hadron Collider, foreseen for 2029, requires the replacement of the ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk). The expected ultimate total integrated luminosity of 4000 fb(-1) means that the strip part of the ITk detector will be exposed to the total particle fluences and ionizing doses reaching the values of 1.6 center dot 10(15) MeVn(eq)/cm(2) and 0.66MGy, respectively, including a safety factor of 1.5. Radiation hard n(+)-in-p micro-strip sensors were developed by the ATLAS ITk strip collaboration and are produced by Hamamatsu Photonics K.K. The active area of each ITk strip sensor is delimited by the n-implant bias ring, which is connected to each individual n(+) implant strip by a polysilicon bias resistor. The total resistance of the polysilicon bias resistor should be within a specified range to keep all the strips at the same potential, prevent the signal discharge through the grounded bias ring and avoid the readout noise increase. While the polysilicon is a ubiquitous semiconductor material, the fluence and temperature dependence of its resistance is not easily predictable, especially for the tracking detector with the operational temperature significantly below the values typical for commercial microelectronics. Dependence of the resistance of polysilicon bias resistor on the temperature, as well as on the total delivered fluence and ionizing dose, was studied on the specially-designed test structures called ATLAS Testchips, both before and after their irradiation by protons, neutrons, and gammas to the maximal expected fluence and ionizing dose. The resistance has an atypical negative temperature dependence. It is different from silicon, which shows that the grain boundary has a significant contribution to the resistance. We discuss the contributions by parameterizing the activation energy of the polysilicon resistance as a function of the temperature for unirradiated and irradiated ATLAS Testchips.
Address [Latonova, V.; Federicova, P.; Kroll, J.; Kvasnicka, J.; Mikestikova, M.] Acad Sci Czech Republ, Inst Phys, Slovance 2, Prague 8, Czech Republic, Email: vera.latonova@cern.ch
Corporate Author Thesis
Publisher (down) Elsevier 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:001035405300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5601
Permanent link to this record
 

 
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 Thesis
Publisher (down) Elsevier 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:001080223500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5704
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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 Thesis
Publisher (down) 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
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Author Bernabeu, J.; Espinoza, C.; Mavromatos, N.E.
Title Cosmological constant and local gravity Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 8 Pages 084002 - 7pp
Keywords
Abstract We discuss the linearization of Einstein equations in the presence of a cosmological constant, by expanding the solution for the metric around a flat Minkowski space-time. We demonstrate that one can find consistent solutions to the linearized set of equations for the metric perturbations, in the Lorentz gauge, which are not spherically symmetric, but they rather exhibit a cylindrical symmetry. We find that the components of the gravitational field satisfying the appropriate Poisson equations have the property of ensuring that a scalar potential can be constructed, in which both contributions, from ordinary matter and Lambda > 0, are attractive. In addition, there is a novel tensor potential, induced by the pressure density, in which the effect of the cosmological constant is repulsive. We also linearize the Schwarzschild-de Sitter exact solution of Einstein's equations ( due to a generalization of Birkhoff's theorem) in the domain between the two horizons. We manage to transform it first to a gauge in which the 3-space metric is conformally flat and, then, make an additional coordinate transformation leading to the Lorentz gauge conditions. We compare our non-spherically symmetric solution with the linearized Schwarzschild-de Sitter metric, when the latter is transformed to the Lorentz gauge, and we find agreement. The resulting metric, however, does not acquire a proper Newtonian form in terms of the unique scalar potential that solves the corresponding Poisson equation. Nevertheless, our solution is stable, in the sense that the physical energy density is positive.
Address [Bernabeu, Jose; Espinoza, Catalina] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Valencia, Spain
Corporate Author Thesis
Publisher (down) 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000277205000057 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 460
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Author Estevez, E. et al; Algora, A.; Rubio, B.; Bernabeu, J.; Nacher, E.; Tain, J.L.; Gadea, A.; Agramunt, J.
Title beta-decay study of (150)Er, (152)Yb, and (156)Yb: Candidates for a monoenergetic neutrino beam facility Type Journal Article
Year 2011 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 84 Issue 3 Pages 034304 - 6pp
Keywords
Abstract The beta decays of (150)Er, (152)Yb, and (156)Yb nuclei are investigated using the total absorption spectroscopy technique. These nuclei can be considered possible candidates for forming the beam of a monoenergetic neutrino beam facility based on the electron capture (EC) decay of radioactive nuclei. Our measurements confirm that for the cases studied the EC decay proceeds mainly to a single state in the daughter nucleus.
Address [Aguado, MEE; Algora, A; Rubio, B; Bernabeu, J; Nacher, E; Tain, JL; Gadea, A; Agramunt, J] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: algora@ific.uv.es
Corporate Author Thesis
Publisher (down) 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 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000294566900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 752
Permanent link to this record