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Author Barducci, D.; Bertuzzo, E.; Caputo, A.; Hernandez, P.
Title Minimal flavor violation in the see-saw portal Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 185 - 28pp
Keywords Neutrino Physics; Beyond Standard Model; CP violation
Abstract We consider an extension of the Standard Model with two singlet leptons, with masses in the electroweak range, that induce neutrino masses via the see-saw mechanism, plus a generic new physics sector at a higher scale, A. We apply the minimal flavor violation (MFV) principle to the corresponding Effective Field Theory (nu SMEFT) valid at energy scales E << A. We identify the irreducible sources of lepton flavor and lepton number violation at the renormalizable level, and apply the MFV ansatz to derive the scaling of the Wilson coefficients of the nu SMEFT operators up to dimension six. We highlight the most important phenomenological consequences of this hypothesis in the rates for exotic Higgs decays, the decay length of the heavy neutrinos, and their production modes at present and future colliders. We also comment on possible astrophysical implications.
Address [Barducci, Daniele] Univ Roma La Sapienza, Dipartimento Fis, Piazzale Aldo Moro 5, I-00185 Rome, Italy, Email: daniele.barducci@roma1.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:000546965800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4462
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Author Calibbi, L.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O.
Title Muon and electron g – 2 and lepton masses in flavor models Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 087 - 23pp
Keywords Precision QED; Beyond Standard Model; Effective Field Theories; Quark Masses and SM Parameters
Abstract The stringent experimental bound on μ-> e gamma is compatible with a simultaneous and sizable new physics contribution to the electron and muon anomalous magnetic moments (g – 2)(l) (l = e, mu), only if we assume a non-trivial flavor structure of the dipole operator coefficients. We propose a mechanism in which the realization of the (g – 2)(l) correction is manifestly related to the mass generation through a flavor symmetry. A radiative flavon correction to the fermion mass gives a contribution to the anomalous magnetic moment. In this framework, we introduce a chiral enhancement from a non-trivial O(1) quartic coupling of the scalar potential. We show that the muon and electron anomalies can be simultaneously explained in a vast region of the parameter space with predicted vector-like mediators of masses as large as M chi is an element of [0.6, 2.5] TeV.
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000542705000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4443
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Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C.
Title Search for the lepton flavour violating decay B+ -> K+mu(-)tau(+) using Bs20 decays Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 129 - 19pp
Keywords B physics; Beyond Standard Model; Flavor physics; Hadron-Hadron scattering (experiments); Rare decay
Abstract A search is presented for the lepton flavour violating decay B+ -> K+mu (-)tau (+) using a sample of proton-proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9 fb(-1). The tau leptons are selected inclusively, primarily via decays with a single charged particle. The four-momentum of the tau lepton is determined by using B+ mesons from Bs20 -> B+K- decays. No significant excess is observed, and an upper limit is set on the branching fractionB(B+-> K+mu (-)tau (+))<3.9x10(-5)at90%confidence level.The obtained limit is comparable to the world-best limit.
Address [Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: maria.vieites.diaz@cern.ch
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:000545615700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4454
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Author Bernard, V.; Descotes-Genon, S.; Vale Silva, L.
Title Constraining the gauge and scalar sectors of the doublet left-right symmetric model Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 088 - 64pp
Keywords Beyond Standard Model; GUT
Abstract We consider a left-right symmetric extension of the Standard Model where the spontaneous breakdown of the left-right symmetry is triggered by doublets. The electroweak rho parameter is protected from large corrections in this Doublet Left-Right Model (DLRM), contrary to the triplet case. This allows in principle for more diverse patterns of symmetry breaking. We consider several constraints on the gauge and scalar sectors of DLRM: the unitarity of scattering processes involving gauge bosons with longitudinal polarisations, the radiative corrections to the muon Delta r parameter and the electroweak precision observables measured at the Z pole and at low energies. Combining these constraints within the frequentist CKMfitter approach, we see that the fit pushes the scale of left-right symmetry breaking up to a few TeV, while favouring an electroweak symmetry breaking triggered not only by the SU (2)(L) x SU (2)(R) bi-doublet, which is the case most commonly considered in the literature, but also by the SU (2)(L) doublet.
Address [Bernard, Veronique] Univ Paris Saclay, Univ Paris Sud, Grp Phys Theor, Inst Phys Nucl,UMR 8606,CNRS, F-91405 Orsay, France, Email: veronique.bernard@ijclab.in2p3.fr;
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:000569357600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4533
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Author Hooper, D.; Leane, R.K.; Tsai, Y.D.; Wegsman, S.; Witte, S.J.
Title A systematic study of hidden sector dark matter: application to the gamma-ray and antiproton excesses Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 163 - 38pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract In hidden sector models, dark matter does not directly couple to the particle content of the Standard Model, strongly suppressing rates at direct detection experiments, while still allowing for large signals from annihilation. In this paper, we conduct an extensive study of hidden sector dark matter, covering a wide range of dark matter spins, mediator spins, interaction diagrams, and annihilation final states, in each case determining whether the annihilations are s-wave (thus enabling efficient annihilation in the universe today). We then go on to consider a variety of portal interactions that allow the hidden sector annihilation products to decay into the Standard Model. We broadly classify constraints from relic density requirements and dwarf spheroidal galaxy observations. In the scenario that the hidden sector was in equilibrium with the Standard Model in the early universe, we place a lower bound on the portal coupling, as well as on the dark matter's elastic scattering cross section with nuclei. We apply our hidden sector results to the observed Galactic Center gamma-ray excess and the cosmic-ray antiproton excess. We find that both of these excesses can be simultaneously explained by a variety of hidden sector models, without any tension with constraints from observations of dwarf spheroidal galaxies.
Address [Hooper, Dan; Tsai, Yu-Dai] Fermilab Natl Accelerator Lab, Fermilab, Batavia, IL 60510 USA, Email: dhooper@fnal.gov;
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:000555828300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4491
Permanent link to this record