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Author Lopez-Ibañez, M.L.; Melis, A.; Jay Perez, M.; Rahat, M.H.; Vives, O.
Title Constraining low-scale flavor models with (g-2)(mu) and lepton flavor violation Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 105 Issue 3 Pages 035021 - 21pp
Keywords
Abstract We present here two concrete examples of models where a sub-TeV scale breaking of their respective T-13 and A(5) flavor symmetries is able to account for the recently observed discrepancy in the muon anomalous magnetic moment, (g – 2)(mu). Similarities in the flavor structures of the charged-lepton Yukawa matrix and dipole matrix yielding (g – 2)(mu) give rise to strong constraints on low-scale flavor models when bounds from lepton flavor violation (LFV) are imposed. These constraints place stringent limits on the off- diagonal Yukawa structure, suggesting a mostly (quasi)diagonal texture for models with a low flavor breaking scale A(f). We argue that many of the popular flavor models in the literature designed to explain the fermion masses and mixings are not suitable for reproducing the observed discrepancy in (g – 2)(mu), which requires a delicate balance of maintaining a low flavor scale while simultaneously satisfying strong LFV constraints.
Address [Lopez-Ibanez, M. L.] Chinese Acad Sci, Inst Theoret Phys, CAS Key Lab Theoret Phys, Beijing 100190, Peoples R China, Email: maloi2@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:000767363800008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5167
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Author Han, C.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.; Yang, J.M.
Title Anomaly-free leptophilic axionlike particle and its flavor violating tests Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 103 Issue 3 Pages 035028 - 7pp
Keywords
Abstract Motivated by the recent Xenon1T result, we study a leptophilic flavor-dependent anomaly-free axionlike particle (ALP) and its effects on charged-lepton flavor violation. We present two representative models. The first one considers that the ALP origins from the flavon that generates the charged-lepton masses. The second model assumes a larger flavor symmetry such that more general mixings in the charged-lepton are possible, while maintaining flavor-dependent ALP couplings. We find that a keV ALP explaining the Xenon1T result is still viable for lepton flavor violation and stellar cooling astrophysical limits. On the other hand, if the Xenon1T result is confirmed, future charged-lepton flavor violation measurements can be complementary to probe such a possibility.
Address [Han, C.] Sun Yat Sen Univ, Sch Phys, Guangzhou 510275, Guangdong, Peoples R China, Email: hanchch@mail.sysu.edu.cn;
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:000621593200009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4739
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Author Gambino, P.; Melis, A.; Simula, S.
Title Extraction of heavy-quark-expansion parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 96 Issue 1 Pages 014511 - 17pp
Keywords
Abstract We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to similar or equal to 4 times the physical b-quark mass. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with N-f = 2 + 1 + 1 dynamical quarks at three values of the lattice spacing (a similar or equal to 0.062; 0.082; 0.089 fm) with pion masses in the range M-pi similar or equal to 210-450 MeV. The heavy-quark mass is simulated directly on the lattice up to similar or equal to 3 times the physical charm mass. The interpolation to the physical b-quark mass is performed using the ETMC ratio method, based on ratios of the meson masses computed at nearby heavy-quark masses, and adopting the kinetic mass scheme. The extrapolation to the physical pion mass and to the continuum limit yields m(b)(kin) (1 GeV) = 4.61(20) GeV, which corresponds to (m) over bar (b) ((m) over bar (b)) 4.26(18) GeV in the (MS) over bar scheme. The lattice data are analyzed in terms of the heavy-quark expansion (HQE) and the matrix elements of dimension-four and dimension-five operators are extracted with a good precision, namely,(Lambda) over bar = 0.552(26) GeV, mu(2)(pi) = 0.321(32) GeV2, and mu(2)(G)(m(b)) = 0.253(25) GeV2. The data also allow for a rough estimate of the dimension-six operator matrix elements. As the HQE parameters play a crucial role in the inclusive determination of the Cabibbo-Kobayashi-Maskawa matrix elements V-ub and V-cb, their precise determination on the lattice may eventually validate and improve the analyses based on fits to the semileptonic moments.
Address [Gambino, P.] Univ Turin, Dipartimento Fis, Via P Giuria 1, I-10125 Turin, Italy
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:000406298500005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3224
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Author Lubicz, V.; Melis, A.; Simula, S.
Title Masses and decay constants of D-(s)* and B-(s)* mesons with N-f=2+1+1 twisted mass fermions Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 96 Issue 3 Pages 034524 - 10pp
Keywords
Abstract We present a lattice calculation of the masses and decay constants of D-(s)* and B-(s)* mesons using the gauge configurations produced by the European Twisted Mass Collaboration (ETMC) with N-f=2+1+1 dynamical quarks at three values of the lattice spacing a similar to(0.06-0.09) fm. Pion masses are simulated in the range M-pi similar or equal to(210-450) MeV, while the strange and charm sea-quark masses are close to their physical values. We compute the ratios of vector to pseudoscalar masses and decay constants for various values of the heavy-quark mass mh in the range 0.7m(c)(phys) less than or similar to m(h) less than or similar to 3m(c)(phys). In order to reach the physical b-quark mass, we exploit the Heavy Quark Effective Theory prediction that, in the static limit of infinite heavy-quark mass, the considered ratios are equal to one. At the physical point our results are: M-D*/M-D=1.0769(79), M-D*(s)/M-Ds=1.0751(56), f(D)*/f(D)=1.078(36), f(D)*s/f(Ds)=1.087(20), M-B*/M-B=1.0078(15), M-B*(s)/M-Bs=1.0083(10), f(B)*/f(B)=0.958(22) and f(B)*s/f(Bs)=0.974(10). Combining them with the experimental values of the pseudoscalar meson masses (used as input to fix the quark masses) and the values of the pseudoscalar decay constants calculated by ETMC, we get: M-D*=2013(14) MeV, M-D*(s)=2116(11) MeV, f(D)*=223.5(8.4) MeV, f(D)*(s)=268.8(6.6) MeV, M-B*=5320.5(7.6) MeV, M-B*(s)=5411.36(5.3) MeV, f(B)*=185.9(7.2) MeV and f(B)*(s)=223.1(5.4) MeV.
Address [Lubicz, V.] Univ Roma Tre, Dip Matemat & Fis, I-00146 Rome, Italy
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:000408626300006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3282
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Author Calibbi, L.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.
Title Implications of the Muon g-2 result on the flavour structure of the lepton mass matrix Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume (down) 81 Issue 10 Pages 929 - 11pp
Keywords
Abstract The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by theMuon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for this discrepancy but these models are much more restricted, as they would also generate offdiagonal entries in the dipole moment matrix. Therefore, if we assume that the observed discrepancy in the muon g – 2 is explained by the contributions of a low-energy flavor symmetry, lepton flavour violating processes can constrain the structure of the lepton mass matrices and therefore the flavour symmetries themselves predicting these structures. We apply these ideas to several discrete flavour symmetries popular in the leptonic sector, such as Delta(27), A(4), and A(5) proportional to CP.
Address [Calibbi, Lorenzo] Nankai Univ, Sch Phys, Tianjin 300071, Peoples R China, Email: calibbi@nankai.edu.cn;
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:000709829900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5017
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Author Lopez-Ibañez, M.L.; Melis, A.; Jay Perez, M.; Vives, O.
Title Slepton non-universality in the flavor-effective MSSM Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 11 Issue 11 Pages 162 - 27pp
Keywords Quark Masses and SM Parameters; Supersymmetric Standard Model; Super-symmetry Breaking; Supersymmetric Effective Theories
Abstract Supersymmetric theories supplemented by an underlying flavor-symmetry G(f) provide a rich playground for model building aimed at explaining the flavor structure of the Standard Model. In the case where supersymmetry breaking is mediated by gravity, the soft-breaking Lagrangian typically exhibits large tree-level flavor violating e ff ects, even if it stems from an ultraviolet flavor-conserving origin. Building on previous work, we continue our phenomenological analysis of these models with a particular emphasis on leptonicflavor observables. We consider three representative models which aim to explain the flavor structure of the lepton sector, with symmetry groups G(f) = Delta (27), A(4); and S-3.
Address [Luisa Lopez-Ibanez, M.; Melis, Aurora; Jay Perez, M.; Vives, Oscar] Univ Valencia, Dept Fis Teor, Dr Moliner 50, Burjassot, Valencia, Spain, Email: m.luisa.lopez-ibanez@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:000416356500006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3382
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Author de Medeiros Varzielas, I.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.
Title Controlled flavor violation in the MSSM from a unified Delta(27) flavor symmetry Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 09 Issue 9 Pages 047 - 22pp
Keywords Beyond Standard Model; Supersymmetric Standard Model; Quark Masses and SM Parameters
Abstract We study the phenomenology of a unified supersymmetric theory with a flavor symmetry Delta(27). The model accommodates quark and lepton masses, mixing angles and CP phases. In this model, the Dirac and Majorana mass matrices have a unified texture zero structure in the (1, 1) entry that leads to the Gatto-Sartori-Tonin relation between the Cabibbo angle and ratios of the masses in the quark sectors, and to a natural departure from zero of the theta 13(l) angle in the lepton sector. We derive the flavor structures of the trilinears and soft mass matrices, and show their general non-universality. This causes large flavor violating effects. As a consequence, the parameter space for this model is constrained, allowing it to be (dis)proven by flavor violation searches in the next decade. Although the results are model specific, we compare them to previous studies to show similar flavor effects (and associated constraints) are expected in general in supersymmetric flavor models, and may be used to distinguish them.
Address [Varzielas, Ivo de Medeiros] Univ Lisbon, Inst Super Tecn, Dept Fis, CFTP, Ave Rovisco Pais 1, P-1049 Lisbon, Portugal, Email: ivo.de@udo.edu;
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:000444676300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3735
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Author Bjorkeroth, F.; de Medeiros Varzielas, I.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.
Title Leptogenesis in Delta(27) with a universal texture zero Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 09 Issue 9 Pages 050 - 24pp
Keywords Beyond Standard Model; GUT; Neutrino Physics
Abstract We investigate the possibility of viable leptogenesis in an appealing Delta(27) model with a universal texture zero in the (1,1) entry. The model accommodates the mass spectrum, mixing and CP phases for both quarks and leptons and allows for grand unification. Flavoured Boltzmann equations for the lepton asymmetries are solved numerically, taking into account both N-1 and N-2 right-handed neutrino decays. The N-1-dominated scenario is successful and the most natural option for the model, with M-1 is an element of [10(9), 10(12)] GeV, and M-1/M-2 is an element of [0.002, 0.1], which constrains the parameter space of the underlying model and yields lower bounds on the respective Yukawa couplings. Viable leptogenesis is also possible in the N-2-dominated scenario, with the asymmetry in the electron flavour protected from N-1 washout by the texture zero. However, this occurs in a region of parameter space which has a stronger mass hierarchy M-1/M-2< 0.002, and M-2 relatively close to M-3, which is not a natural expectation of the Delta(27) model.
Address [Bjorkeroth, Fredrik] INFN, Lab Nazl Frascati, CP 13, I-100044 Frascati, Italy, Email: fredrik.bjorkeroth@lnf.infn.it;
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:000485053000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4139
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Author Han, C.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.; Yang, J.M.
Title Anomaly-free ALP from non-Abelian flavor symmetry Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 08 Issue 8 Pages 306 - 21pp
Keywords Axions and ALPs; Flavour Symmetries; Lepton Flavour Violation (charged)
Abstract Motivated by the XENON1T excess in electron-recoil measurements, we investigate the prospects of probing axion-like particles (ALP) in lepton flavor violation experiments. In particular, we identify such ALP as a pseudo-Goldstone from the spontaneous breaking of the flavor symmetries that explain the mixing structure of the Standard Model leptons. We present the case of the flavor symmetries being a non-Abelian U(2) and the ALP originating from its U(1) subgroup, which is anomaly-free with the Standard Model group. We build two explicit realistic examples that reproduce leptonic masses and mixings and show that the ALP which is consistent with XENON1T anomaly could be probed by the proposed LFV experiments.
Address [Han, C.] Sun Yat Sen Univ, Sch Phys, Guangzhou 510275, Peoples R China, Email: hanchch@mail.sysu.edu.cn;
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:000848742400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5348
Permanent link to this record
 

 
Author Lopez-Ibañez, M.L.; Melis, A.; Meloni, D.; Vives, O.
Title Lepton flavor violation and neutrino masses from A(5) and CP in the non-universal MSSM Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 06 Issue 6 Pages 047 - 34pp
Keywords Beyond Standard Model; Neutrino Physics; Quark Masses and SM Parameters; Supersymmetric Standard Model
Abstract We analyze the phenomenological consequences of embedding a flavor symmetry based on the groups A(5) and CP in a supersymmetric framework. We concentrate on the leptonic sector, where two different residual symmetries are assumed to be conserved at leading order for charged and neutral leptons. All possible realizations to generate neutrino masses at tree level are investigated. Sizable flavor violating effects in the charged lepton sector are unavoidable due to the non-universality of soft-breaking terms determined by the symmetry. We derive testable predictions for the neutrino spectrum, lepton mixing and flavor changing processes with non-trivial relations among observables.
Address [Lopez-Ibanez, M. L.; Meloni, Davide] Univ Roma Tre, Dipartimento Matemat & Fis, Via Vasca Navale 84, I-00146 Rome, Italy, Email: maloi2@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:000471630100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4057
Permanent link to this record