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Author Lattanzi, M.; Gerbino, M.; Freese, K.; Kane, G.; Valle, J.W.F.
Title Cornering (quasi) degenerate neutrinos with cosmology Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages (up) 213 - 24pp
Keywords Cosmology of Theories beyond the SM; Neutrino Physics
Abstract In light of the improved sensitivities of cosmological observations, we examine the status of quasi-degenerate neutrino mass scenarios. Within the simplest extension of the standard cosmological model with massive neutrinos, we find that quasi-degenerate neutrinos are severely constrained by present cosmological data and neutrino oscillation experiments. We find that Planck 2018 observations of cosmic microwave background (CMB) anisotropies disfavour quasi-degenerate neutrino masses at 2.4 Gaussian sigma 's, while adding baryon acoustic oscillations (BAO) data brings the rejection to 5.9 sigma 's. The highest statistical significance with which one would be able to rule out quasi-degeneracy would arise if the sum of neutrino masses is Sigma m(v) = 60 meV (the minimum allowed by neutrino oscillation experiments); indeed a sensitivity of 15 meV, as expected from a combination of future cosmological probes, would further improve the rejection level up to 17 sigma. We discuss the robustness of these projections with respect to assumptions on the underlying cosmological model, and also compare them with bounds from beta decay endpoint and neutrinoless double beta decay studies.
Address [Lattanzi, Massimiliano; Gerbino, Martina] Ist Nazl Fis Nucl, Sez Ferrara, Polo Sci & Tecnol,Edificio C,Via Saragat 1, I-44122 Ferrara, Italy, Email: lattanzi@fe.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:000588150500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4603
Permanent link to this record
 

 
Author Bonilla, C.; Ma, E.; Peinado, E.; Valle, J.W.F.
Title Two-loop Dirac neutrino mass and WIMP dark matter Type Journal Article
Year 2016 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 762 Issue Pages (up) 214-218
Keywords Neutrino masses and mixing; Dark matter stability
Abstract We propose a “scotogenic” mechanism relating small neutrino mass and cosmological dark matter. Neutrinos are Dirac fermions with masses arising only in two-loop order through the sector responsible for dark matter. Two triality symmetries ensure both dark matter stability and strict lepton number conservation at higher orders. A global spontaneously broken U(1) symmetry leads to a physical Diraconthat induces invisible Higgs decays which add up to the Higgs to dark matter mode. This enhances sensitivities to spin-independent WIMP dark matter search below m(h)/2.
Address [Bonillaa, Cesar; Valle, Jose W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Edificio Inst Paterna,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: cesar.bonilla@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000388473700029 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2979
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Author Batra, A.; Bharadwaj, P.; Mandal, S.; Srivastava, R.; Valle, J.W.F.
Title Phenomenology of the simplest linear seesaw mechanism Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages (up) 221 - 48pp
Keywords Specific BSM Phenomenology; Sterile or Heavy Neutrinos; Baryon; Lepton Number Violation; Other Weak Scale BSM Models
Abstract The linear seesaw mechanism provides a simple way to generate neutrino masses. In addition to Standard Model particles, it includes quasi-Dirac leptons as neutrino mass mediators, and a leptophilic scalar doublet seeding small neutrino masses. Here we review its associated physics, including restrictions from theory and phenomenology. The model yields potentially detectable μ-> e gamma rates as well as distinctive signatures in the production and decay of heavy neutrinos ( N-i) and the charged Higgs boson (H-+/-) arising from the second scalar doublet. We have found that production processes such as e(+) e(-) -> NN, e- gamma -> NH- and e(+) e(-) -> H (+) H- followed by the decay chain H-+/--> l(+/-) (i) N, N -> l`(+/-) (j) W (-/+) leads to striking lepton number violation signatures at high energies which may probe the Majorana nature of neutrinos.
Address [Batra, Aditya; Bharadwaj, Praveen; Srivastava, Rahul] Indian Inst Sci Educ & Res Bhopal, Dept Phys, Bhopal Bypass Rd, Bhopal 462066, India, Email: aditya.batra@tecnico.ulisboa.pt;
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:001039968700005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5605
Permanent link to this record
 

 
Author Fontes, D.; Romao, J.C.; Valle, J.W.F.
Title Electroweak breaking and Higgs boson profile in the simplest linear seesaw model Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages (up) 245 - 28pp
Keywords Beyond Standard Model; Higgs Physics; Neutrino Physics
Abstract We examine the simplest realization of the linear seesaw mechanism within the Standard Model gauge structure. Besides the standard scalar doublet, there are two lepton-number-carrying scalars, a nearly inert SU(2)(L) doublet and a singlet. Neutrino masses result from the spontaneous violation of lepton number, implying the existence of a Nambu-Goldstone boson. Such “majoron” would be copiously produced in stars, leading to stringent astrophysical constraints. We study the profile of the Higgs bosons in this model, including their effective couplings to the vector bosons and their invisible decay branching ratios. A consistent electroweak symmetry breaking pattern emerges with a compressed spectrum of scalars in which the “Standard Model” Higgs boson can have a sizeable invisible decay into the invisible majorons.
Address [Fontes, Duarte; Romao, Jorge C.] Univ Lisbon, Inst Super Tecn, Dept Fis, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: duartefontes@tecnico.ulisboa.pt;
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:000495737300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4199
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Author Barreiros, D.M.; Joaquim, F.R.; Srivastava, R.; Valle, J.W.F.
Title Minimal scoto-seesaw mechanism with spontaneous CP violation Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages (up) 249 - 21pp
Keywords Neutrino Physics; CP violation
Abstract We propose simple scoto-seesaw models to account for dark matter and neutrino masses with spontaneous CP violation. This is achieved with a single horizontal Z8 discrete symmetry, broken to a residual Z2 subgroup responsible for stabilizing dark matter. CP is broken spontaneously via the complex vacuum expectation value of a scalar singlet, inducing leptonic CP-violating effects. We find that the imposed Z8 symmetry pushes the values of the Dirac CP phase and the lightest neutrino mass to ranges already probed by ongoing experiments, so that normal-ordered neutrino masses can be cornered by cosmological observations and neutrinoless double beta decay experiments.
Address [Barreiros, D. M.; Joaquim, F. R.] Univ Lisbon, Dept Fis, Inst Super Tecn, Av Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: debora.barreiros@tecnico.ulisboa.pt;
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:000646917200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4814
Permanent link to this record