Records |
Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Diamanti, R.; Ando, S.; Gariazzo, S.; Mena, O.; Weniger, C. |
Title |
Cold dark matter plus not-so-clumpy dark relics |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
06 |
Issue |
6 |
Pages |
008 - 17pp |
Keywords |
cosmological parameters from CMBR; dark matter theory; dwarfs galaxies; particle physics – cosmology connection |
Abstract |
Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark relics might exist. These could be warm, hot, or even contribute as dark radiation. We present here a comprehensive study of two-component dark matter scenarios, where the first component is assumed to be cold, and the second is a non-cold thermal relic. Considering the cases where the non-cold dark matter species could be either a fermion or a boson, we derive consistent upper limits on the non-cold dark relic energy density for a very large range of velocity dispersions, covering the entire range from dark radiation to cold dark matter. To this end, we employ the latest Planck Cosmic Microwave Background data, the recent BOSS DR11 and other Baryon Acoustic Oscillation measurements, and also constraints on the number of Milky Way satellites, the latter of which provides a measure of the suppression of the matter power spectrum at the smallest scales due to the free-streaming of the non-cold dark matter component. We present the results on the fraction f(ncdm) of non-cold dark matter with respect to the total dark matter for different ranges of the non-cold dark matter masses. We find that the 2 sigma limits for non-cold dark matter particles with masses in the range 1-10 keV are f(ncdm) <= 0.29 (0.23) for fermions (bosons), and for masses in the 10-100 keV range they are f(ncdm) <= 0.43 (0.45), respectively. |
Address |
[Diamanti, Roberta; Ando, Shin'ichiro; Weniger, Christoph] Univ Amsterdam, Inst Phys, GRAPPA, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands, Email: r.diamanti@uva.nl; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000403482400010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3174 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Di Bari, P.; King, S.F.; Hossain Rahat, M. |
Title |
Gravitational waves from phase transitions and cosmic strings in neutrino mass models with multiple majorons |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
068 - 31pp |
Keywords |
Cosmology of Theories BSM; Early Universe Particle Physics; Phase Transitions in the Early Universe |
Abstract |
We explore the origin of Majorana masses within the majoron model and how this can lead to the generation of a distinguishable primordial stochastic background of gravitational waves. We first show how in the simplest majoron model only a contribution from cosmic string can be within the reach of planned experiments. We then consider extensions containing multiple complex scalars, demonstrating how in this case a spectrum comprising contributions from both a strong first order phase transition and cosmic strings can naturally emerge. We show that the interplay between multiple scalar fields can amplify the phase transition signal, potentially leading to double peaks over the wideband sloped spectrum from cosmic strings. We also underscore the possibility of observing such a gravitational wave background to provide insights into the reheating temperature of the universe. We conclude highlighting how the model can be naturally combined with scenarios addressing the origin of matter of the universe, where baryogenesis occurs via leptogenesis and a right-handed neutrino plays the role of dark matter. |
Address |
[Di Bari, Pasquale; King, Stephen F.; Rahat, Moinul Hossain] Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, England, Email: P.Di-Bari@soton.ac.uk; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001256020200004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6182 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
de Salas, P.F.; Pastor, S. |
Title |
Relic neutrino decoupling with flavour oscillations revisited |
Type |
Journal Article |
Year |
2016 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
07 |
Issue |
7 |
Pages |
051 - 18pp |
Keywords |
cosmological neutrinos; particle physics – cosmology connection; physics of the; early universe; neutrino properties |
Abstract |
We study the decoupling process of neutrinos in the early universe in the presence of three-flavour oscillations. The evolution of the neutrino spectra is found by solving the corresponding momentum-dependent kinetic equations for the neutrino density matrix, including for the first time the proper collision integrals for both diagonal and off-diagonal elements. This improved calculation modifies the evolution of the off-diagonal elements of the neutrino density matrix and changes the deviation from equilibrium of the frozen neutrino spectra. However, it does not vary the contribution of neutrinos to the cosmological energy density in the form of radiation, usually expressed in terms of the effective number of neutrinos, N-eff. We find a value of N-eff = 3.045, in agreement with previous theoretical calculations and consistent with the latest analysis of Planck data. This result does not depend on the ordering of neutrino masses. We also consider the effect of non-standard neutrino-electron interactions (NSI), predicted in many theoretical models where neutrinos acquire mass. For two sets of NSI parameters allowed by present data, we find that Neff can be reduced down to 3.040 or enhanced up to 3.059. |
Address |
[de Salas, Pablo F.; Pastor, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pabrerde@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000381830000052 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2784 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Davidek, T.; Fiorini, L. |
Title |
Search for Lepton-Flavor-Violating Decays of Bosons With the ATLAS Detector |
Type |
Journal Article |
Year |
2020 |
Publication |
Frontiers in Physics |
Abbreviated Journal |
Front. Physics |
Volume |
8 |
Issue |
|
Pages |
149 - 13pp |
Keywords |
lepton-flavor-violating decays; Z boson; Higgs boson; ATLAS; LHC; particle physics |
Abstract |
The quest for lepton-flavor-violating processes at the LHC represents one of the key searches for new physics beyond the Standard Model. This review summarizes the direct searches for lepton-flavor-violating decays of heavy bosons with the ATLAS detector, using proton-proton collisions at the center-of-mass energy of 13 TeV. |
Address |
[Davidek, Tomas] Charles Univ Prague, Inst Particle & Nucl Phys IPNP, Fac Math & Phys, Prague, Czech Republic, Email: tomas.davidek@cern.ch; |
Corporate Author |
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Thesis |
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Publisher |
Frontiers Media Sa |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2296-424x |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000536708200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4416 |
Permanent link to this record |
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Author ![sorted by Author field, descending order (down)](img/sort_desc.gif) |
Cosme, C.; Figueroa, D.G.; Loayza, N. |
Title |
Gravitational wave production from preheating with trilinear interactions |
Type |
Journal Article |
Year |
2023 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
05 |
Issue |
5 |
Pages |
023 - 30pp |
Keywords |
physics of the early universe; primordial gravitational waves (theory); gravita-tional waves; sources; particle physics-cosmology connection |
Abstract |
We investigate the production of gravitational waves (GWs) during preheating with monomial/polynomial inflationary potentials, considering a trilinear coupling & phi;x2 between a singlet inflaton & phi; and a daughter scalar field x. For sufficiently large couplings, the trilinear interaction leads to an exponential production of x particles and, as a result, a large stochastic GW background (SGWB) is generated throughout the process. We study the linear and non-linear dynamics of preheating with lattice simulations, following the production of GWs through all relevant stages. We find that large couplings lead to SGWBs with amplitudes today that can reach up to h2 �(0) GW <^> 5 & BULL; 10-9. These backgrounds are however peaked at high frequencies fp > 5 & BULL; 106 Hz, which makes them undetectable by current/planned GW observatories. As the amount of GWs produced is in any case remarkable, we discuss the prospects for probing the SGWB indirectly by using constraints on the effective number of relativistic species in the universe Neff. |
Address |
[Cosme, Catarina; Figueroa, Daniel G.; Loayza, Nicolas] Univ Valencia CSIC, Inst Fis Corpuscular IFIC, Parc Cientif UV,C-Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: catarina.cosme@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:001038638500007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5660 |
Permanent link to this record |