Records |
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 |
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Area |
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Expedition |
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Conference |
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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) |
de Salas, P.F.; Gariazzo, S.; Mena, O.; Ternes, C.A.; Tortola, M. |
Title |
Neutrino Mass Ordering From Oscillations and Beyond: 2018 Status and Future Prospects |
Type |
Journal Article |
Year |
2018 |
Publication |
Frontiers in Astronomy and Space Sciences |
Abbreviated Journal |
Front. Astron. Space Sci. |
Volume |
5 |
Issue |
|
Pages |
36 - 50pp |
Keywords |
neutrino mass ordering; neutrino oscillations; neutrinoless double beta (0v beta beta) decay; large scale structure formation; cosmic microwave Background (CMB); neutrino masses and flavor mixing |
Abstract |
The ordering of the neutrino masses is a crucial input for a deep understanding of flavor physics, and its determination may provide the key to establish the relationship among the lepton masses and mixings and their analogous properties in the quark sector. The extraction of the neutrino mass ordering is a data-driven field expected to evolve very rapidly in the next decade. In this review, we both analyse the present status and describe the physics of subsequent prospects. Firstly, the different current available tools to measure the neutrino mass ordering are described. Namely, reactor, long-baseline (accelerator and atmospheric) neutrino beams, laboratory searches for beta and neutrinoless double beta decays and observations of the cosmic background radiation and the large scale structure of the universe are carefully reviewed. Secondly, the results from an up-to-date comprehensive global fit are reported: the Bayesian analysis to the 2018 publicly available oscillation and cosmological data sets provides strong evidence for the normal neutrino mass ordering vs. the inverted scenario, with a significance of 3.5 standard deviations. This preference for the normal neutrino mass ordering is mostly due to neutrino oscillation measurements. Finally, we shall also emphasize the future perspectives for unveiling the neutrinomass ordering. In this regard, apart from describing the expectations from the aforementioned probes, we also focus on those arising from alternative and novel methods, as 21 cm cosmology, core-collapse supernova neutrinos and the direct detection of relic neutrinos. |
Address |
[de Salas, Pablo F.; Gariazzo, Stefano; Mena, Olga; Ternes, Christoph A.; Tortola, Mariam] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: omena@ific.uv.es |
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 |
2296-987x |
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:000446788500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3755 |
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.; Gariazzo, S.; Martinez-Mirave, P.; Pastor, S.; Tortola, M. |
Title |
Cosmological radiation density with non-standard neutrino-electron interactions |
Type |
Journal Article |
Year |
2021 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
820 |
Issue |
|
Pages |
136508 - 9pp |
Keywords |
Neutrino interactions; Non-standard neutrino interactions; Cosmology; Neutrino oscillations |
Abstract |
Neutrino non-standard interactions (NSI) with electrons are known to alter the picture of neutrino de coupling from the cosmic plasma. NSI modify both flavour oscillations through matter effects, and the annihilation and scattering between neutrinos and electrons and positrons in the thermal plasma. In view of the forthcoming cosmological observations, we perform a precision study of the impact of non universal and flavour-changing NSI on the effective number of neutrinos, Neff. We present the variation of Neff arising from the different NSI parameters and discuss the existing degeneracies among them, from cosmology alone and in relation to the current bounds from terrestrial experiments. Even though cosmology is generally less sensitive to NSI than these experiments, we find that future cosmological data would provide competitive and complementary constraints for some of the couplings and their combinations. |
Address |
[de Salas, Pablo F.] Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden, Email: pablo.fernandez@fysik.su.se; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-2693 |
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:000713101800031 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5023 |
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.; Gariazzo, S.; Lesgourgues, J.; Pastor, S. |
Title |
Calculation of the local density of relic neutrinos |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
09 |
Issue |
9 |
Pages |
034 - 24pp |
Keywords |
cosmological neutrinos; dark matter simulations; galaxy clustering; neutrino experiments |
Abstract |
Nonzero neutrino masses are required by the existence of flavour oscillations, with values of the order of at least 50 meV. We consider the gravitational clustering of relic neutrinos within the Milky Way, and used the N – one-body simulation technique to compute their density enhancement factor in the neighbourhood of the Earth with respect to the average cosmic density. Compared to previous similar studies, we pushed the simulation down to smaller neutrino masses, and included an improved treatment of the baryonic and dark matter distributions in the Milky Way. Our results are important for future experiments aiming at detecting the cosmic neutrino background, such as the Princeton Tritium Observatory for Light, Early-universe, Massive-neutrino Yield (PTOLEMY) proposal. We calculate the impact of neutrino clustering in the Milky Way on the expected event rate for a PTOLEMY-like experiment. We find that the effect of clustering remains negligible for the minimal normal hierarchy scenario, while it enhances the event rate by 10 to 20% (resp. a factor 1.7 to 2.5) for the minimal inverted hierarchy scenario (resp. a degenerate scenario with 150 meV masses). Finally we compute the impact on the event rate of a possible fourth sterile neutrino with a mass of 1.3 eV. |
Address |
[de Salas, P. F.; Gariazzo, S.; Pastor, S.] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pabferde@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:000411617000002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3308 |
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.; Gariazzo, S.; Laveder, M.; Pastor, S.; Pisanti, O.; Truong, N. |
Title |
Cosmological bounds on neutrino statistics |
Type |
Journal Article |
Year |
2018 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
03 |
Issue |
3 |
Pages |
050 - 18pp |
Keywords |
cosmological neutrinos; neutrino properties; big bang nucleosynthesis; cosmological parameters from CMBR |
Abstract |
We consider the phenomenological implications of the violation of the Pauli exclusion principle for neutrinos, focusing on cosmological observables such as the spectrum of Cosmic Microwave Background anisotropies, Baryon Acoustic Oscillations and the primordial abundances of light elements. Neutrinos that behave (at least partly) as bosonic particles have a modified equilibrium distribution function that implies a different influence on the evolution of the Universe that, in the case of massive neutrinos, can not be simply parametrized by a change in the effective number of neutrinos. Our results show that, despite the precision of the available cosmological data, only very weak bounds can be obtained on neutrino statistics, disfavouring a more bosonic behaviour at less than 2 sigma. |
Address |
[de Salas, P. F.; Gariazzo, S.; Pastor, S.] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pabferde@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 |
|
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 |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000428984100005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3551 |
Permanent link to this record |