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Author Bhattacharya, A.; Esmaili, A.; Palomares-Ruiz, S.; Sarcevic, I.
Title Probing decaying heavy dark matter with the 4-year IceCube HESE data Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 027 - 36pp
Keywords dark matter theory; neutrino astronomy; neutrino detectors; ultra high energy photons and neutrinos
Abstract After the first four years of data taking, the IceCube neutrino telescope has observed 54 high-energy starting events (HESE) with deposited energies between 20TeV and 2PeV. The background from atmospheric muons and neutrinos is expected to be of about 20 events, all below 100TeV, thus pointing towards the astrophysical origin of about 8 events per year in that data set. However, their precise origin remains unknown. Here, we perform a detailed analysis of this event sample (considering simultaneously the energy, hemisphere and topology of the events) by assuming two contributions for the signal events: an isotropic power-law flux and a flux from decaying heavy dark matter. We fit the mass and lifetime of the dark matter and the normalization and spectral index of an isotropic power-law flux, for various decay channels of dark matter. We find that a significant contribution from dark matter decay is always slightly favored, either to explain the excess below 100TeV, as in the case of decays to quarks or, as in the case of neutrino channels, to explain the three multi-PeV events. Also, we consider the possibility to interpret all the data by dark matter decays only, considering various combinations of two decay channels. We show that the decaying dark matter scenario provides a better fit to HESE data than the isotropic power-law flux.
Address (up) [Bhattacharya, Atri] Univ Liege, Space Sci Technol & Astrophys Res STAR Inst, Bat B5a, B-4000 Liege, Belgium, Email: a.bhattacharya@ulg.ac.be;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000406420500009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3243
Permanent link to this record
 
 
Author Bhattacharya, A.; Esmaili, A.; Palomares-Ruiz, S.; Sarcevic, I.
Title Update on decaying and annihilating heavy dark matter with the 6-year IceCube HESE data Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 03 Issue 5 Pages 051 - 30pp
Keywords dark matter theory; ultra high energy photons and neutrinos
Abstract In view of the IceCube's 6-year high-energy starting events (HESE) sample, we revisit the possibility that the updated data may be better explained by a combination of neutrino fluxes from dark matter decay and an isotropic astrophysical power-law than purely by the latter. We find that the combined two-component flux qualitatively improves the fit to the observed data over a purely astrophysical one, and discuss how these updated fits compare against a similar analysis done with the 4-year HESE data. We also update fits involving dark matter decay via multiple channels, without any contribution from the astrophysical flux. We find that a DM-only explanation is not excluded by neutrino data alone. Finally, we also consider the possibility of a signal from dark matter annihilations and perform analogous analyses to the case of decays, commenting on its implications.
Address (up) [Bhattacharya, Atri] Univ Liege, Space Sci Technol & Astrophys Res STAR Inst, Bat B5a, B-4000 Liege, Belgium, Email: a.bhattacharya@ulg.ac.be;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000469808500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4038
Permanent link to this record
 
 
Author Blennow, M.; Fernandez-Martinez, E.; Hernandez-Garcia, J.; Lopez-Pavon, J.; Marcano, X.; Naredo-Tuero, D.
Title Bounds on lepton non-unitarity and heavy neutrino mixing Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 030 - 41pp
Keywords Electroweak Precision Physics; Neutrino Mixing; Sterile or Heavy Neutrinos
Abstract We present an updated and improved global fit analysis of current flavour and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active flavours. This new analysis is motivated by new and updated experimental results on key observables such as V-ud, the invisible decay width of the Z boson and the W boson mass. It also improves upon previous studies by considering the full correlations among the different observables and explicitly calibrating the test statistic, which may present significant deviations from a & chi;(2) distribution. The results are provided for three different Type-I seesaw scenarios: the minimal scenario with only two additional right-handed neutrinos, the next to minimal one with three extra neutrinos, and the most general one with an arbitrary number of heavy neutrinos that we parametrise via a generic deviation from a unitary leptonic mixing matrix. Additionally, we also analyze the case of generic deviations from unitarity of the leptonic mixing matrix, not necessarily induced by the presence of additional neutrinos. This last case relaxes some correlations among the parameters and is able to provide a better fit to the data. Nevertheless, inducing only leptonic unitarity deviations avoiding both the correlations implied by the right-handed neutrino extension as well as more strongly constrained operators is challenging and would imply significantly more complex UV completions.
Address (up) [Blennow, Mattias] KTH Royal Inst Technol, AlbaNova Univ Ctr, Sch Engn Sci, Dept Phys, Roslagstullsbacken 21, S-10691 Stockholm, Sweden, Email: emb@kth.se;
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:001044930400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5607
Permanent link to this record
 
 
Author Capozzi, F.; Saviano, N.
Title Neutrino Flavor Conversions in High-Density Astrophysical and Cosmological Environments Type Journal Article
Year 2022 Publication Universe Abbreviated Journal Universe
Volume 8 Issue 2 Pages 94 - 23pp
Keywords astrophysical neutrinos; neutrino oscillations; supernovae; neutron star mergers; early Universe; sterile neutrinos
Abstract Despite being a well understood phenomenon in the context of current terrestrial experiments, neutrino flavor conversions in dense astrophysical environments probably represent one of the most challenging open problems in neutrino physics. Apart from being theoretically interesting, such a problem has several phenomenological implications in cosmology and in astrophysics, including the primordial nucleosynthesis of light elements abundance and other cosmological observables, nucleosynthesis of heavy nuclei, and the explosion of massive stars. In this review, we briefly summarize the state of the art on this topic, focusing on three environments: early Universe, core-collapse supernovae, and compact binary mergers.
Address (up) [Capozzi, Francesco] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest, Paterna 46980, Spain, Email: fcapozzi@ific.uv.es;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000762069300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5146
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Author Borexino Collaboration (Bellini, G. et al); Pena-Garay, C.
Title Absence of a day-night asymmetry in the Be-7 solar neutrino rate in Borexino Type Journal Article
Year 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 707 Issue 1 Pages 22-26
Keywords Solar neutrinos; Day-night effect; CPT violation; Neutrino oscillations
Abstract We report the result of a search for a day-night asymmetry in the Be-7 solar neutrino interaction rate in the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The measured asymmetry is A(dn) = 0.001 +/- 0.012 (stat) +/- 0.007 (syst), in agreement with the prediction of MSW-LMA solution for neutrino oscillations. This result disfavors MSW oscillations with mixing parameters in the LOW region at more than 8.5 sigma. This region is, for the first time, strongly disfavored without the use of reactor anti-neutrino data and therefore the assumption of CPT symmetry. The result can also be used to constrain some neutrino oscillation scenarios involving new physics.
Address (up) [Carraro, C.; Davini, S.; Guardincerri, E.; Manuzio, G.; Pallavicini, M.; Perasso, S.; Salvo, C.; Testera, G.; Zavatarelli, S.] Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy, Email: marco.pallavicini@ge.infn.it
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:000299757000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 901
Permanent link to this record
 
 
Author Cermeño, M.; Perez-Garcia, M.A.; Lineros, R.A.
Title Enhanced neutrino emissivities in pseudoscalar-mediated dark matter annihilation in neutron stars Type Journal Article
Year 2018 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 863 Issue 2 Pages 157 - 9pp
Keywords dark matter; neutrinos; stars: neutron
Abstract We calculate neutrino emissivities from self-annihilating dark matter (DM) (chi) in the dense and hot stellar interior of a (proto)neutron star. Using a model where DM interacts with nucleons in the stellar core through a pseudoscalar boson (a) we find that the neutrino production rates from the dominant reaction channels chi -> nu(nu) over bar or chi chi -> aa, with subsequent decay of the mediator a -> nu(nu) over bar, could locally match and even surpass those of the standard neutrinos from the modified nuclear URCA processes at early ages. We find that the emitting region can be localized in a tiny fraction of the star (less than a few percent of the core volume) and the process can last its entire lifetime for some cases under study. We discuss the possible consequences of our results for stellar cooling in light of existing DM constraints.
Address (up) [Cermeno, M.; Perez-Garcia, M. A.] Univ Salamanca, Dept Fundamental Phys, Plaza Merced S-N, E-37008 Salamanca, Spain, Email: marinacgavilan@usal.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-637x ISBN Medium
Area Expedition Conference
Notes WOS:000442222700019 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3696
Permanent link to this record
 
 
Author Chianese, M.; Fiorillo, D.F.G.; Hajjar, R.; Miele, G.; Saviano, N.
Title Constraints on heavy decaying dark matter with current gamma-ray measurements Type Journal Article
Year 2021 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 11 Issue 11 Pages 035 - 13pp
Keywords dark matter theory; ultra high energy photons and neutrinos
Abstract Among the several strategies for indirect searches of dark matter, a very promising one is to look for the gamma-rays from decaying dark matter. Here we use the most up-to-date upper bounds on the gamma-ray flux from 10(5) to 10(11) GeV, obtained from CASA-MIA, KASCADE, KASCADE-Grande, Pierre Auger Observatory, Telescope Array and EAS-MSU. We obtain global limits on dark matter lifetime in the range of masses in m(DM) = [10(7)-10(15)] GeV. We provide the bounds for a set of decay channels chosen as representatives. The constraints derived here are new and cover a region of the parameter space not yet explored. We compare our results with the projected constraints from future neutrino telescopes, in order to quantify the improvement that will be obtained by the complementary high-energy neutrino searches.
Address (up) [Chianese, Marco; Fiorillo, Damiano F. G.; Miele, Gennaro] Univ Napoli Federico II, Dipartimento Fis Ettore Pancini, Complesso Univ Monte S Angelo, I-80126 Naples, Italy, Email: chianese@na.infn.it;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000727716400012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5051
Permanent link to this record
 
 
Author Chun, E.J.; Cvetic, G.; Dev, P.S.B.; Drewes, M.; Fong, C.S.; Garbrecht, B.; Hambye, T.; Harz, J.; Hernandez, P.; Kim, C.S.; Molinaro, E.; Nardi, E.; Racker, J.; Rius, N.; Zamora-Saa, J.
Title Probing leptogenesis Type Journal Article
Year 2018 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 33 Issue 5-6 Pages 1842005 - 99pp
Keywords Neutrino interactions; nonstandard-model neutrinos; right-handed neutrinos; extensions of electroweak gauge sector; supersymmetric models
Abstract The focus of this paper lies on the possible experimental tests of leptogenesis scenarios. We consider both leptogenesis generated from oscillations, as well as leptogenesis from out-of-equilibrium decays. As the Akhmedov-Rubakov-Smirnov (ARS) mechanism allows for heavy neutrinos in the GeV range, this opens up a plethora of possible experimental tests, e.g. at neutrino oscillation experiments, neutrinoless double beta decay, and direct searches for neutral heavy leptons at future facilities. In contrast, testing leptogenesis from out-of-equilibrium decays is a quite difficult task. We comment on the necessary conditions for having successful leptogenesis at the TeV-scale. We further discuss possible realizations and their model specific testability in extended seesaw models, models with extended gauge sectors, and supersymmetric leptogenesis. Not being able to test high-scale leptogenesis directly, we present a way to falsify such scenarios by focusing on their washout processes. This is discussed specifically for the left-right symmetric model and the observation of a heavy W-R, as well as model independently when measuring Delta L = 2 washout processes at the LHC or neutrinoless double beta decay.
Address (up) [Chun, E. J.] Korea Inst Adv Study, Seoul 02455, South Korea, Email: jharz@lpthe.jussieu.fr
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-751x ISBN Medium
Area Expedition Conference
Notes WOS:000426586100006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3507
Permanent link to this record
 
 
Author Coito, L.; Faubel, C.; Herrero-Garcia, J.; Santamaria, A.; Titov, A.
Title Sterile neutrino portals to Majorana dark matter: effective operators and UV completions Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 085 - 36pp
Keywords Models for Dark Matter; Particle Nature of Dark Matter; Sterile or Heavy Neutrinos; Baryon/Lepton Number Violation
Abstract Stringent constraints on the interactions of dark matter with the Standard Model suggest that dark matter does not take part in gauge interactions. In this regard, the possibility of communicating between the visible and dark sectors via gauge singlets seems rather natural. We consider a framework where the dark matter talks to the Standard Model through its coupling to sterile neutrinos, which generate active neutrino masses. We focus on the case of Majorana dark matter, with its relic abundance set by thermal freeze-out through annihilations into sterile neutrinos. We use an effective field theory approach to study the possible sterile neutrino portals to dark matter. We find that both lepton-number-conserving and lepton-number-violating operators are possible, yielding an interesting connection with the Dirac/Majorana character of active neutrinos. In a second step, we open the different operators and outline the possible renormalisable models. We analyse the phenomenology of the most promising ones, including a particular case in which the Majorana mass of the sterile neutrinos is generated radiatively.
Address (up) [Coito, Leonardo] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: leonardo.coito@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:000836782300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5340
Permanent link to this record
 
 
Author Coloma, P.; López-Pavón, J.; Molina-Bueno, L.; Urrea, S.
Title New physics searches using ProtoDUNE and the CERN SPS accelerator Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 134 - 18pp
Keywords New Light Particles; Sterile or Heavy Neutrinos
Abstract The exquisite capabilities of liquid Argon Time Projection Chambers make them ideal to search for weakly interacting particles in Beyond the Standard Model scenarios. Given their location at CERN the ProtoDUNE detectors may be exposed to a flux of such particles, produced in the collisions of 400 GeV protons (extracted from the Super Proton Synchrotron accelerator) on a target. Here we point out the interesting possibilities that such a setup offers to search for both long-lived unstable particles (Heavy Neutral Leptons, axion-like particles, etc) and stable particles (e.g. light dark matter, or millicharged particles). Our results show that, under conservative assumptions regarding the expected luminosity, this setup has the potential to improve over present bounds for some of the scenarios considered. This could be done within a short timescale, using facilities that are already in place at CERN, and without interfering with the experimental program in the North Area at CERN.
Address (up) [Coloma, Pilar] UAM, Inst Fis Teor, CSIC, Calle Nicolas Cabrera 13-15, E-28049 Madrid, Spain, Email: pilar.coloma@ift.csic.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:001155849200017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5948
Permanent link to this record