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Author Arbelaez, C.; Helo, J.C.; Hirsch, M.
Title Long-lived heavy particles in neutrino mass models Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 5 Pages 055001 - 15pp
Keywords
Abstract (up) All extensions of the standard model that generate Majorana neutrino masses at the electroweak scale introduce some heavy mediators, either fermions and/or scalars, weakly coupled to leptons. Here, by “heavy,” we mean implicitly the mass range between a few 100 GeV up to, say, roughly 2 TeV, such that these particles can be searched for at the LHC. We study decay widths of these mediators for several different tree-level neutrino mass models. The models we consider range from the simplest d = 5 seesaw up to d = 11 neutrino mass models. For each of the models, we identify the most interesting parts of the parameter space, where the heavy mediator fields are particularly long lived and can decay with experimentally measurable decay lengths. One has to distinguish two different scenarios, depending on whether fermions or scalars are the lighter of the heavy particles. For fermions, we find that the decay lengths correlate with the inverse of the overall neutrino mass scale. Thus, since no lower limit on the lightest neutrino mass exists, nearly arbitrarily long decay lengths can be obtained for the case in which fermions are the lighter of the heavy particles. For charged scalars, on the other hand, there exists a maximum value for the decay length in these models. This maximum value depends on the model and on the electric charge of the scalar under consideration but can at most be of the order of a few millimeters. Interestingly, independent of the model, this maximum occurs always in a region of parameter space, where leptonic and gauge boson final states have similar branching ratios, i.e., where the observation of lepton number-violating final states from scalar decays is possible.
Address [Arbelaez, Carolina] Univ Tecn Federico Santa Maria, Casilla 110-V, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl;
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:000483583000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4127
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Author Arbelaez, C.; Cepedello, R.; Helo, J.C.; Hirsch, M.; Kovalenko, S.
Title How many 1-loop neutrino mass models are there? Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 023 - 29pp
Keywords Other Weak Scale BSM Models; Models for Dark Matter; Neutrino Interactions
Abstract (up) It is well-known that at tree-level the d = 5 Weinberg operator can be generated in exactly three different ways, the famous seesaw models. In this paper we study the related question of how many phenomenologically consistent 1-loop models one can construct at d=5. First, we discuss that there are two possible classes of 1-loop neutrino mass models, that allow avoiding stable charged relics: (i) models with dark matter candidates and (ii) models with “exits”. Here, we define “exits” as particles that can decay into standard model fields. Considering 1-loop models with new scalars and fermions, we find in the dark matter class a total of (115+203) models, while in the exit class we find (38+368) models. Here, 115 is the number of DM models, which require a stabilizing symmetry, while 203 is the number of models which contain a dark matter candidate, which maybe accidentally stable. In the exit class the 38 refers to models, for which one (or two) of the internal particles in the loop is a SM field, while the 368 models contain only fields beyond the SM (BSM) in the neutrino mass diagram. We then study the RGE evolution of the gauge couplings in all our 1-loop models. Many of the models in our list lead to Landau poles in some gauge coupling at rather low energies and there is exactly one model which unifies the gauge couplings at energies above 10(15) GeV in a numerically acceptable way.
Address [Arbelaez, Carolina] Univ Tecn Federico Santa Maria, Dept Phys, Ave Espana 1680, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl;
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:000835685500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5320
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Author Arbelaez, C.; Cottin, G.; Helo, J.C.; Hirsch, M.
Title Long-lived charged particles and multilepton signatures from neutrino mass models Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 9 Pages 095033 - 13pp
Keywords
Abstract (up) Lepton number violation (LNV) is usually searched for by the LHC collaborations using the same-sign dilepton plus jet signature. In this paper, we discuss multilepton signals of LNV that can arise with experimentally interesting rates in certain loop models of neutrino mass generation. Interestingly, in such models, the observed smallness of the active neutrino masses, together with the high multiplicity of the final states, leads in large parts of the viable parameter space of such models to the prediction of long-lived charged particles, which leave highly ionizing tracks in the detectors. We focus on one particular one-loop neutrino mass model in this class and discuss its LHC phenomenology in some detail.
Address [Arbelaez, Carolina] Univ Tecn Federico Santa Maria, Av Espana 1680,Casilla 110-5, Valparaiso 2340000, Chile, Email: carolina.arbelaez@usm.cl;
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:000535451000011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4403
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Author Arbelaez, C.; Cepedello, R.; Fonseca, R.M.; Hirsch, M.
Title (g-2) anomalies and neutrino mass Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 7 Pages 075005 - 14pp
Keywords
Abstract (up) Motivated by the experimentally observed deviations from standard model predictions, we calculate the anomalous magnetic moments a(alpha) = (g – 2)(alpha) for a = e, μin a neutrino mass model originally proposed by Babu, Nandi, and Tavartkiladze (BNT). We discuss two variants of the model: the original model, and a minimally extended version with an additional hypercharge-zero triplet scalar. While the original BNT model can explain a(mu), only the variant with the triplet scalar can explain both experimental anomalies. The heavy fermions of the model can be produced at the high-luminosity LHC, and in the part of parameter space where the model explains the experimental anomalies it predicts certain specific decay patterns for the exotic fermions.
Address [Arbelaez, Carolina] Univ Tecn Federico Santa Maria, Casilla 110-5, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl;
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:000576053400004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4557
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Author Arbelaez, C.; Gonzalez, M.; Hirsch, M.; Kovalenko, S.G.
Title QCD corrections and long-range mechanisms of neutrinoless double beta decay Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 94 Issue 9 Pages 096014 - 5pp
Keywords
Abstract (up) Recently it has been demonstrated that QCD corrections are numerically important for short-range mechanisms (SRM) of neutrinoless double beta decay (0 nu beta beta) mediated by heavy particle exchange. This is due to the effect of color mismatch for certain effective operators, which leads to mixing between different operators with vastly different nuclear matrix elements (NMEs). In this note we analyze the QCD corrections for long-range mechanisms (LRM), due to diagrams with light-neutrino exchange between a Standard Model (V-A)chi(V-A) and a beyond the SM lepton number violating vertex. We argue that in contrast to the SRM in the LRM case, there is no operator mixing from color-mismatched operators. This is due to a combined effect of the nuclear short-range correlations and color invariance. As a result, the QCD corrections to the LRM amount to an effect no more than 60%, depending on the operator in question. Although less crucial, taken into account QCD running makes theoretical predictions for 0 nu beta beta-decay more robust also for LRM diagrams. We derive the current experimental constraints on the Wilson coefficients for all LRM effective operators.
Address [Arbelaez, C.; Gonzalez, M.; Kovalenko, S. G.] Univ Tecn Federico Santa Maria, Ctr Cient Tecnol Valparaiso, Casilla 110-V, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl;
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:000388823800017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2888
Permanent link to this record