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Author Beltran, R.; Cottin, G.; Helo, J.C.; Hirsch, M.; Titov, A.; Wang, Z.S.
Title Long-lived heavy neutral leptons at the LHC: four-fermion single-N-R operators Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue (up) 1 Pages 044 - 18pp
Keywords Beyond Standard Model; Effective Field Theories; Neutrino Physics
Abstract Interest in searches for heavy neutral leptons (HNLs) at the LHC has increased considerably in the past few years. In the minimal scenario, HNLs are produced and decay via their mixing with active neutrinos in the Standard Model (SM) spectrum. However, many SM extensions with HNLs have been discussed in the literature, which sometimes change expectations for LHC sensitivities drastically. In the N-R SMEFT, one extends the SM effective field theory with operators including SM singlet fermions, which allows to study HNL phenomenology in a “model independent” way. In this paper, we study the sensitivity of ATLAS to HNLs in the N-R SMEFT for four-fermion operators with a single HNL. These operators might dominate both production and decay of HNLs, and we find that new physics scales in excess of 20 TeV could be probed at the high-luminosity LHC.
Address [Beltran, Rebeca; Hirsch, Martin] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Apartado 22085, E-46071 Valencia, Spain, Email: rebeca.beltran@ifis.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:000742012500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5079
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Author Beltran, R.; Cottin, G.; Helo, J.C.; Hirsch, M.; Titov, A.; Wang, Z.S.
Title Long-lived heavy neutral leptons from mesons in effective field theory Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue (up) 1 Pages 015 - 38pp
Keywords New Light Particles; SMEFT; Sterile or Heavy Neutrinos
Abstract In the framework of the low-energy effective field theory of the Standard Model extended with heavy neutral leptons (HNLs), we calculate the production rates of HNLs from meson decays triggered by dimension-six operators. We consider both lepton number-conserving and lepton-number-violating four-fermion operators involving either a pair of HNLs or a single HNL. Assuming that HNLs are long-lived, we perform simulations and investigate the reach of the proposed far detectors at the high-luminosity LHC to (i) active-heavy neutrino mixing and (ii) the Wilson coefficients associated with the effective operators, for HNL masses below the mass of the B-meson. We further convert the latter to the associated new-physics scales. Our results show that scales in excess of hundreds of TeV and the active-heavy mixing squared as small as 10(-15 )can be probed by these experiments.
Address [Beltran, Rebeca; Hirsch, Martin] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Apartado 22085, E-46071 Valencia, Spain, Email: rebeca.beltran@ific.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:000909520000005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5455
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Author Beltran, R.; Günther, J.; Hirsch, M.; Titov, A.; Wang, Z.S.
Title Heavy neutral leptons from kaons in effective field theory Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue (up) 11 Pages 115014 - 19pp
Keywords
Abstract In the framework of the low -energy effective theory containing, in addition to the Standard -Model fields, heavy neutral leptons (HNLs), we compute the decay rates of neutral and charged kaons into HNLs. We consider both lepton -number -conserving and lepton -number -violating four-fermion operators, taking into account also the contribution of active -heavy neutrino mixing. Assuming that the produced HNLs are longlived, we perform simulations and calculate the sensitivities of future long -lived -particle (LLP) detectors at the high -luminosity LHC as well as the near detector of the Deep Underground Neutrino Experiment (DUNE -ND) to the considered scenario. When applicable, we also recast the existing bounds on the minimal mixing case obtained by NA62, T2K, and PS191. Our findings show that, while the future LHC LLP detectors can probe currently allowed parameter space only in certain benchmark scenarios, DUNE -ND should be sensitive to parameter space beyond the current bounds in almost all the benchmark scenarios, and, for some of the effective operators considered, it can even probe new -physics scales in excess of 3000 TeV.
Address [Beltran, Rebeca; Hirsch, Martin] Univ Valencia, CSIC, AHEP Grp, Inst Fis Corpuscular, Apartado 22085, E-46071 Valencia, Spain, Email: rebeca.beltran@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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001250419300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6165
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Author Chala, M.; Titov, A.
Title Neutrino masses in the Standard Model effective field theory Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 104 Issue (up) 3 Pages 035002 - 8pp
Keywords
Abstract We compute the leading-logarithmic correction to the neutrino mass matrix in the Standard Model effective field theory (SMEFT) to dimension seven. In the limit of negligible lepton and down-type quark Yukawa couplings, it receives contributions from the Weinberg dimension-five operator as well as from 11 dimension-six and five dimension-seven independent interactions. Two of the main implications we derive from this result are the following. First, we find dimension-seven operators which, despite violating lepton number, do not renormalize neutrino masses at one loop. And second, we demonstrate that the presence of dimension-six operators around the TeV scale can modify the Standard Model prediction by up to O(50%). Our result comprises also one step forward towards the renormalization of the SMEFT to order v(3)/Lambda(3).
Address [Chala, Mikael] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: mikael.chala@ugr.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:000681157900003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4924
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Author Feruglio, F.; Gherardi, V.; Romanino, A.; Titov, A.
Title Modular invariant dynamics and fermion mass hierarchies around tau = i Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue (up) 5 Pages 242 - 26pp
Keywords Beyond Standard Model; Neutrino Physics; Supersymmetric Standard Model; Compactification and String Models
Abstract We discuss fermion mass hierarchies within modular invariant flavour models. We analyse the neighbourhood of the self-dual point tau = i, where modular invariant theories possess a residual Z(4) invariance. In this region the breaking of Z(4) can be fully described by the spurion epsilon approximate to tau – i, that flips its sign under Z(4). Degeneracies or vanishing eigenvalues of fermion mass matrices, forced by the Z(4) symmetry at tau = i, are removed by slightly deviating from the self-dual point. Relevant mass ratios are controlled by powers of vertical bar epsilon vertical bar. We present examples where this mechanism is a key ingredient to successfully implement an hierarchical spectrum in the lepton sector, even in the presence of a non-minimal Kahler potential.
Address [Feruglio, Ferruccio; Titov, Arsenii] Univ Padua, Dipartimento Fis & Astron G Galilei, Via Marzolo 8, I-35131 Padua, Italy, Email: feruglio@pd.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:000738737200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5070
Permanent link to this record