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Author Bonilla, C.; Modak, T.; Srivastava, R.; Valle, J.W.F.
Title U(1)(B3-3L2) gauge symmetry as a simple description of b -> s anomalies Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 9 Pages 095002 - 11pp
Keywords
Abstract (down) We present a simple U(1)(B3-3L2) gauge standard model extension that can easily account for the anomalies in R(K) and R(K*) reported by LHCb. The model is economical in its setup and particle content. Among the standard model fermions, only the third generation quark family and the second generation leptons transform nontrivially under the new U(1)(B3-3L2) symmetry. This leads to lepton nonuniversality and flavor changing neutral currents involving the second and third quark families. We discuss the relevant experimental constraints and some implications.
Address [Bonilla, Cesar] Tech Univ Munich, Phys Dept T30d, James Franck Str, D-85748 Garching, Germany, Email: cesar.bonilla@tum.de;
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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000448926500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3785
Permanent link to this record
 
 
Author Belle II Collaboration (Abudinen, F. et al); Gomis, P.; Marinas, C.
Title Search for Axionlike Particles Produced in e(+)e(-) Collisions at Belle II Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 125 Issue 16 Pages 161806 - 9pp
Keywords
Abstract (down) We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e(+)e(-) -> gamma a, a -> gamma gamma in the mass range 0.2 < m(a) < 9.7 GeV/c(2) using data corresponding to an integrated luminosity of (445 +/- 3) pb(-1). Light pseudoscalars interacting predominantly with standard model gauge bosons (so-called axionlike particles or ALPs) are frequently postulated in extensions of the standard model. We find no evidence for ALPs and set 95% confidence level upper limits on the coupling strength g(a gamma gamma) of ALPs to photons at the level of 10(-3) GeV-1. The limits are the most restrictive to date for 0.2 < m(a) < 1 GeV/c(2).
Address [Polat, G.; Serrano, J.; Zani, L.] Aix Marseille Univ, CPPM, IN2P3, CNRS, F-13288 Marseille, France
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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000577074900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4567
Permanent link to this record
 
 
Author Double Chooz collaboration (Abrahao, T. et al); Novella, P.
Title Search for signatures of sterile neutrinos with Double Chooz Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 81 Issue 8 Pages 775 - 14pp
Keywords
Abstract (down) We present a search for signatures of neutrino mixing of electron anti-neutrinos with additional hypothetical sterile neutrino flavors using the Double Chooz experiment. The search is based on data from 5 years of operation of Double Chooz, including 2 years in the two-detector configuration. The analysis is based on a profile likelihood, i.e. comparing the data to the model prediction of disappearance in a data-to-data comparison of the two respective detectors. The analysis is optimized for a model of three active and one sterile neutrino. It is sensitive in the typical mass range 5 x 10(-3) eV(2) less than or similar to Delta m(41)(2) less than or similar to 3 x 10(-1) eV(2) for mixing angles downto sin(2) 2 theta(14) greater than or similar to 0.02. No significant disappearance additionally to the conventional disappearance related to theta(13) is observed and correspondingly exclusion bounds on the sterile mixing parameter theta(14) as a function of Delta m(41)(2) are obtained.
Address [Bekman, I; Hellwig, D.; Heuermann, L.; Soldin, P.; Stahl, A.; Wiebusch, C.] Rhein Westfal TH Aachen, Phys Inst 3, D-52056 Aachen, Germany, Email: wiebusch@physik.rwth-aachen.de
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:000691009900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4950
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Search for lepton-flavor-violating decays D-0 -> X(0)e(+/-)mu(-/+) Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 11 Pages 112003 - 11pp
Keywords
Abstract (down) We present a search for seven lepton-flavor-violating neutral charm meson decays of the type D-0 -> X(0)e(+/-)mu(-/+), where X-0 represents a pi(0), K-S(0), (K) over bar*(0), rho(0), phi, omega, or eta meson. The analysis is based on 468 fb(-1) of e(+)e(-) annihilation data collected at or close to the Upsilon(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signals are observed, and we establish 90% confidence level upper limits on the branching fractions in the range (5.0-22.5) x 10(-7). The limits are between 1 and 2 orders of magnitude more stringent than previous measurements.
Address [Lees, J. P.; Poireau, V; Tisserand, V] Univ Savoie, Lab Annecy le Vieux Phys Particules LAPP, IN2P3, CNRS, F-74941 Annecy Le Vieux, France
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000540165400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4429
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Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Search for Rare or Forbidden Decays of the D-0 Meson Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 7 Pages 071802 - 8pp
Keywords
Abstract (down) We present a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type D-0 -> h'(-) h(-) l'(+) l(+) and D-0 -> h'(-) h(+) l'(+/-) l(-/+), where h and h' represent a K or pi meson and l and l' an electron or muon. The analysis is based on 468 fb(-1) of e(+) e(-) annihilation data collected at or close to the Upsilon(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the twelve modes, and we establish 90% confidence level upper limits on the branching fractions in the range (1.0-30.6) x 10(-7). The limits are between 1 and 3 orders of magnitude more stringent than previous measurements.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000515063000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4301
Permanent link to this record
 
 
Author Coito, L.; Faubel, C.; Santamaria, A.
Title Composite Higgs bosons from neutrino condensates in an inverted seesaw scenario Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 7 Pages 075009 - 10pp
Keywords
Abstract (down) We present a realization of the idea that the Higgs boson is mainly a bound state of neutrinos induced by strong four-fermion interactions. The conflicts of this idea with the measured values of the top quark and Higgs boson masses are overcome by introducing, in addition to the right-handed neutrino, a new fermion singlet, which, at low energies, implements the inverse seesaw mechanism. The singlet fermions also develop a scalar bound state that mixes with the Higgs boson. This allows us to obtain a small Higgs boson mass even if the couplings are large, as required in composite scalar scenarios. The model gives the correct masses for the top quark and Higgs boson for compositeness scales below the Planck scale and masses of the new particles above the electroweak scale, so that we obtain naturally a low-scale seesaw scenario for neutrino masses. The theory contains additional scalar particles coupled to the neutral fermions, which could be tested in present and near future experiments.
Address [Coito, Leonardo; Faubel, Carlos; Santamaria, Arcadi] Univ Valencia, Dept Fis Teor, Doctor Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: leonardo.coito@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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000524321800009 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4371
Permanent link to this record
 
 
Author Alcaide, J.; Salvado, J.; Santamaria, A.
Title Fitting flavour symmetries: the case of two-zero neutrino mass textures Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 164 - 18pp
Keywords Neutrino Physics; Quark Masses and SM Parameters
Abstract (down) We present a numeric method for the analysis of the fermion mass matrices predicted in flavour models. The method does not require any previous algebraic work, it offers a chi(2) comparison test and an easy estimate of confidence intervals. It can also be used to study the stability of the results when the predictions are disturbed by small perturbations. We have applied the method to the case of two-zero neutrino mass textures using the latest available fits on neutrino oscillations, derived the available parameter space for each texture and compared them. Textures A(1) and A(2) seem favoured because they give a small chi(2), allow for large regions in parameter space and give neutrino masses compatible with Cosmology limits. The other “allowed” textures remain allowed although with a very constrained parameter space, which, in some cases, could be in conflict with Cosmology. We have also revisited the “forbidden” textures and studied the stability of the results when the texture zeroes are not exact. Most of the forbidden textures remain forbidden, but textures F-1 and F-3 are particularly sensitive to small perturbations and could become allowed.
Address [Alcaide, Julien; Santamaria, Arcadi] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Valencia, Spain, Email: julien.alcaide@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:000440091700010 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3680
Permanent link to this record
 
 
Author Harko, T.; Koivisto, T.S.; Lobo, F.S.N.; Olmo, G.J.; Rubiera-Garcia, D.
Title Coupling matter in modified Q gravity Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 8 Pages 084043 - 13pp
Keywords
Abstract (down) We present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. This is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity Q is nonminimally coupled to the matter Lagrangian. More specifically, we consider a Lagrangian of the form L similar to f(1)(Q) + f(2)(Q)L-M, where f(1) and f(2) are generic functions of Q, and L-M is the matter Lagrangian. This nonminimal coupling entails the nonconservation of the energy-momentum tensor, and consequently the appearance of an extra force. The formulation of the gravity sector in terms of the Q instead of the curvature may result in subtle improvements of the theory. In the context of nonminimal matter couplings, we are therefore motivated to explore whether the new geometrical formulation in terms of the Q, when implemented also in the matter sector, would allow more universally consistent and viable realizations of the nonminimal coupling. Furthermore, we consider several cosmological applications by presenting the evolution equations and imposing specific functional forms of the functions f(1)(Q) and f(2)(Q), such as power-law and exponential dependencies of the nonminimal couplings. Cosmological solutions are considered in two general classes of models, and found to feature accelerating expansion at late times.
Address [Harko, Tiberiu] Babes Bolyai Univ, Dept Phys, Kogalniceanu St, Cluj Napoca 400084, Romania, Email: t.harko@ucl.ac.uk;
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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000448458600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3789
Permanent link to this record
 
 
Author Cepedello, R.; Deppisch, F.F.; Gonzalez, L.; Hati, C.; Hirsch, M.
Title Neutrinoless Double-Beta Decay with Nonstandard Majoron Emission Type Journal Article
Year 2019 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 122 Issue 18 Pages 181801 - 6pp
Keywords
Abstract (down) We present a novel mode of neutrinoless double-beta decay with emission of a light Majoron-like scalar particle phi. We assume it couples via an effective seven-dimensional operator with a (V + A) lepton current and (V +/- A) quark currents leading to a long-range contribution that is unsuppressed by the light neutrino mass. We calculate the total double-beta decay rate and determine the fully differential shape for this mode. We find that future double-beta decay searches are sensitive to scales of the order Lambda(NP) approximate to 1 TeV for the effective operator and a light scalar m(phi) < 0.2 MeV, based on ordinary double-beta decay Majoron searches. The angular and energy distributions can deviate considerably from that of two-neutrino double-beta decay, which is the main background. We point out possible ultraviolet completions where such an effective operator can emerge.
Address [Cepedello, Ricardo; Hirsch, Martin] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Edificio Inst Paterna,Apartado 22085, E-46071 Valencia, Spain, Email: ricepe@ific.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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000467042800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4002
Permanent link to this record
 
 
Author Ferrer-Sanchez, A.; Martin-Guerrero, J.; Ruiz de Austri, R.; Torres-Forne, A.; Font, J.A.
Title Gradient-annihilated PINNs for solving Riemann problems: Application to relativistic hydrodynamics Type Journal Article
Year 2024 Publication Computer Methods in Applied Mechanics and Engineering Abbreviated Journal Comput. Meth. Appl. Mech. Eng.
Volume 424 Issue Pages 116906 - 18pp
Keywords Riemann problem; Euler equations; Machine learning; Neural networks; Relativistic hydrodynamics
Abstract (down) We present a novel methodology based on Physics-Informed Neural Networks (PINNs) for solving systems of partial differential equations admitting discontinuous solutions. Our method, called Gradient-Annihilated PINNs (GA-PINNs), introduces a modified loss function that forces the model to partially ignore high-gradients in the physical variables, achieved by introducing a suitable weighting function. The method relies on a set of hyperparameters that control how gradients are treated in the physical loss. The performance of our methodology is demonstrated by solving Riemann problems in special relativistic hydrodynamics, extending earlier studies with PINNs in the context of the classical Euler equations. The solutions obtained with the GA-PINN model correctly describe the propagation speeds of discontinuities and sharply capture the associated jumps. We use the relative l(2) error to compare our results with the exact solution of special relativistic Riemann problems, used as the reference ''ground truth'', and with the corresponding error obtained with a second-order, central, shock-capturing scheme. In all problems investigated, the accuracy reached by the GA-PINN model is comparable to that obtained with a shock-capturing scheme, achieving a performance superior to that of the baseline PINN algorithm in general. An additional benefit worth stressing is that our PINN-based approach sidesteps the costly recovery of the primitive variables from the state vector of conserved variables, a well-known drawback of grid-based solutions of the relativistic hydrodynamics equations. Due to its inherent generality and its ability to handle steep gradients, the GA-PINN methodology discussed in this paper could be a valuable tool to model relativistic flows in astrophysics and particle physics, characterized by the prevalence of discontinuous solutions.
Address [Ferrer-Sanchez, Antonio; Martin-Guerrero, JoseD.] ETSE UV, Elect Engn Dept, IDAL, Avgda Univ S-N, Valencia 46100, Spain, Email: Antonio.Ferrer-Sanchez@uv.es
Corporate Author Thesis
Publisher Elsevier Science Sa Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0045-7825 ISBN Medium
Area Expedition Conference
Notes WOS:001221797400001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 6126
Permanent link to this record