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Author Gariazzo, S.; Mena, O.; Miralles, V.; Ramirez, H.; Boubekeur, L. url  doi
openurl 
  Title Running of featureful primordial power spectra Type Journal Article
  Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 95 Issue 12 Pages 123534 - 7pp  
  Keywords  
  Abstract Current measurements of the temperature and polarization anisotropy power spectra of the cosmic microwave background (CMB) seem to indicate that the naive expectation for the slow-roll hierarchy within the most simple inflationary paradigm may not be respected in nature. We show that a primordial power spectrum with localized features could in principle give rise to the observed slow-roll anarchy when fitted to a featureless power spectrum. From a model comparison perspective, and assuming that nature has chosen a featureless primordial power spectrum, we find that, while with mock Planck data there is only weak evidence against a model with localized features, upcoming CMB missions may provide compelling evidence against such a nonstandard primordial power spectrum. This evidence could be reinforced if a featureless primordial power spectrum is independently confirmed from bispectrum and/or galaxy clustering measurements.  
  Address [Gariazzo, Stefano; Mena, Olga; Miralles, Victor; Ramirez, Hector] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain  
  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:000404475200004 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3186  
Permanent link to this record
 

 
Author Gariazzo, S.; Giunti, C.; Laveder, M.; Li, Y.F. url  doi
openurl 
  Title Updated global 3+1 analysis of short-baseline neutrino oscillations Type Journal Article
  Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 06 Issue 6 Pages 135 - 38pp  
  Keywords Neutrino Physics; Beyond Standard Model  
  Abstract We present the results of an updated fit of short-baseline neutrino oscillation data in the framework of 3+1 active-sterile neutrino mixing. We first consider v(e) and (v) over bar (e) disappearance in the light of the Gallium and reactor anomalies. We discuss the implications of the recent measurement of the reactor (v) over bar (e) spectrum in the NEOS experiment, which shifts the allowed regions of the parameter space towards smaller values of |U-e1|(2). The beta-decay constraints of the Mainz and Troitsk experiments allow us to limit the oscillation length between about 2 cm and 7 m at 3 sigma for neutrinos with an energy of 1 MeV. The corresponding oscillations can be discovered in a model-independent way in ongoing reactor and source experiments by measuring v(e) and (v) over bar (e), disappearance as a function of distance. We then consider the global fit of the data on short-baseline v(mu)((-)) -> v(e)((-)) transitions in the light of the LSND anomaly, taking into account the constraints from v(e)(( )) and v(mu)((-)) disappearance experiments, including the recent data of the MINOS and IceCube experiments. The combination of the NEOS constraints on |U-e4|(2) and the MINOS and IceCube constraints on |U-mu 4|(2) lead to an unacceptable appearance-disappearance tension which becomes tolerable only in a pragmatic fit which neglects the MiniBooNE low-energy anomaly. The minimization of the global chi(2) in the space of the four mixing parameters Delta m(41)(2), |U-e4|(2), |U-mu 4|(2) and |U-4 tau|(2) leads to three allowed regions with narrow Delta m(41)(2) widths at Delta m(41)(2) approximate to 1.7 (best-fit), 1.3 (at 2 sigma), 2.4 (at 3 sigma) eV(2). The effective amplitude of short-baseline v(mu)((-)) -> v(e)((-)) oscillations is limited by 0.00048 less than or similar to sin(2) 2 nu(e mu) less than or similar to 0.0020 at 3 sigma The restrictions of the allowed regions of the mixing parameters with respect to our previous global fits are mainly due to the NEOS constraints. We present a comparison of the allowed regions of the mixing parameters with the sensitivities of ongoing experiments, which show that it is likely that these experiments will determine in a definitive way if the reactor, Gallium and LSND anomalies are due to active-sterile neutrino oscillations or not.  
  Address [Gariazzo, S.] Univ Valencia, CSIC, Inst Fis Corpusc, Valencia, Spain, Email: gariazzo@ific.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:000404627200001 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3190  
Permanent link to this record
 

 
Author Gariazzo, S.; Escudero, M.; Diamanti, R.; Mena, O. url  doi
openurl 
  Title Cosmological searches for a noncold dark matter component Type Journal Article
  Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 96 Issue 4 Pages 043501 - 11pp  
  Keywords  
  Abstract We explore an extended cosmological scenario where the dark matter is an admixture of cold and additional noncold species. The mass and temperature of the noncold dark matter particles are extracted from a number of cosmological measurements. Among others, we consider tomographic weak lensing data and Milky Way dwarf satellite galaxy counts. We also study the potential of these scenarios in alleviating the existing tensions between local measurements and cosmic microwave background ( CMB) estimates of the S-8 parameter, with S-8 = sigma(8)root Omega(m), and of the Hubble constant H-0. In principle, a subdominant, noncold dark matter particle with a mass m(X) similar to keV, could achieve the goals above. However, the preferred ranges for its temperature and its mass are different when extracted from weak lensing observations and from Milky Way dwarf satellite galaxy counts, since these two measurements require suppressions of the matter power spectrum at different scales. Therefore, solving simultaneously the CMB-weak lensing tensions and the small scale crisis in the standard cold dark matter picture via only one noncold dark matter component seems to be challenging.  
  Address [Gariazzo, Stefano; Escudero, Miguel; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain  
  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:000406911700001 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3236  
Permanent link to this record
 

 
Author de Salas, P.F.; Gariazzo, S.; Lesgourgues, J.; Pastor, S. url  doi
openurl 
  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 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:000411617000002 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3308  
Permanent link to this record
 

 
Author Gariazzo, S.; Mena, O.; Ramirez, H.; Boubekeur, L. url  doi
openurl 
  Title Primordial power spectrum features in phenomenological descriptions of inflation Type Journal Article
  Year 2017 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe  
  Volume 17 Issue Pages 38-45  
  Keywords Inflation; Primordial power spectrum; Sound speed  
  Abstract We extend an alternative, phenomenological approach to inflation by means of an equation of state and a sound speed, both of them functions of the number of e-folds and four phenomenological parameters. This approach captures a number of possible inflationary models, including those with non-canonical kinetic terms or scale-dependent non-gaussianities. We perform Markov Chain Monte Carlo analyses using the latest cosmological publicly available measurements, which include Cosmic Microwave Background (CMB) data from the Planck satellite. Within this parameterization, we discard scale invariance with a significance of about 10 sigma, and the running of the spectral index is constrained as alpha(s) = -0.60(-0.10)(+0.08) x 10(-3) (68% CL errors). The limit on the tensor-to-scalar ratio is r < 0.005 at 95% CL from CMB data alone. We find no significant evidence for this alternative parameterization with present cosmological observations. The maximum amplitude of the equilateral non-gaussianity that we obtain, vertical bar f(NL)(equil)vertical bar < 1, is much smaller than the current Planck mission errors, strengthening the case for future high-redshift, all-sky surveys, which could reach the required accuracy on equilateral non-gaussianities.  
  Address [Gariazzo, Stefano] Univ Turin, Dept Phys, Via P Giuria 1, I-10125 Turin, Italy, Email: omena@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 2212-6864 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000411869100006 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3319  
Permanent link to this record
 

 
Author de Salas, P.F.; Gariazzo, S.; Laveder, M.; Pastor, S.; Pisanti, O.; Truong, N. url  doi
openurl 
  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 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:000428984100005 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3551  
Permanent link to this record
 

 
Author Villanueva-Domingo, P.; Gariazzo, S.; Gnedin, N.Y.; Mena, O. url  doi
openurl 
  Title Was there an early reionization component in our universe? Type Journal Article
  Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 04 Issue 4 Pages 024 - 17pp  
  Keywords cosmological parameters from CMBR; reionization  
  Abstract A deep understanding of the epoch of reionization is still missing in our knowledge of the universe. While future probes will allow us to test the precise evolution of the free electron fraction from redshifts between z similar or equal to 6 and z similar or equal to 20, at present one could ask what kind of reionization processes are allowed by present cosmic microwave background temperature and polarization measurements. An early contribution to reionization could imply a departure from the standard picture where star formation determines the reionization onset. By considering a broad class of possible reionization parameterizations, we find that current data do not require an early reionization component in our universe and that only one marginal class of models, based on a particular realization of reionization, may point to that. In addition, the frequentist Akaike information criterion (AIC) provides strong evidence against alternative reionization histories, favoring the most simple reionization scenario, which describes reionization by means of only one (constant) reionization optical depth tau.  
  Address [Villanueva-Domingo, Pablo; Gariazzo, Stefano; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: pablo.villanueva@ific.uv.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 1475-7516 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000429339200001 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3555  
Permanent link to this record
 

 
Author Gariazzo, S.; Giunti, C.; Laveder, M.; Li, Y.F. url  doi
openurl 
  Title Model-independent (nu)over-bar(e) short-baseline oscillations from reactor spectral ratios Type Journal Article
  Year 2018 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 782 Issue Pages 13-21  
  Keywords  
  Abstract We consider the ratio of the spectra measured in the DANSS neutrino experiment at 12.7 and 10.7 m from a nuclear reactor. These data give a new model-independent indication in favor of short-baseline (nu) over bar (e) oscillations which reinforce the model-independent indication found in the late 2016 in the NEOS experiment. The combined analysis of the NEOS and DANSS spectral ratios in the framework of 3+1 active-sterile neutrino mixing favor short-baseline (nu) over bar (e) oscillations with a statistical significance of 3.7 sigma. The two mixing parameters sin(2)2 nu ee and Delta m(41)(2) are constrained at 2 sigma a narrow-Delta m(41)(2) island at Delta m(41)(2) similar or equal to 1.3 eV(2), with sin(2)2 nu(ee)= 0.049 +/- 0.023(2 sigma). We discuss the implications of the model-independent NEOS+DANSS analysis for the reactor and Gallium anomalies. The NEOS+DANSS model-independent determination of short-baseline (nu) over bar (e) oscillations allows us to analyze the reactor rates without assumptions on the values of the main reactor antineutrino fluxes and the data of the Gallium source experiments with free detector efficiencies. The corrections to the reactor neutrino fluxes and the Gallium detector efficiencies are obtained from the fit of the data. In particular, we confirm the indication in favor of the need for a recalculation of the (235)Ureactor antineutrino flux found in previous studies assuming the absence of neutrino oscillations.  
  Address [Gariazzo, S.] Univ Valencia, CSIC, Inst Fis Corpuscular, Paterna, Valencia, Spain, Email: gariazzo@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:000438486900003 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3662  
Permanent link to this record
 

 
Author Gariazzo, S.; Archidiacono, M.; de Salas, P.F.; Mena, O.; Ternes, C.A.; Tortola, M. url  doi
openurl 
  Title Neutrino masses and their ordering: global data, priors and models Type Journal Article
  Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 03 Issue 3 Pages 011 - 22pp  
  Keywords neutrino masses from cosmology; neutrino properties; cosmological parameters from CMBR; double beta decay  
  Abstract We present a full Bayesian analysis of the combination of current neutrino oscillation, neutrinoless double beta decay and Cosmic Microwave Background observations. Our major goal is to carefully investigate the possibility to single out one neutrino mass ordering, namely Normal Ordering or Inverted Ordering, with current data. Two possible parametrizations (three neutrino masses versus the lightest neutrino mass plus the two oscillation mass splittings) and priors (linear versus logarithmic) are exhaustively examined. We find that the preference for NO is only driven by neutrino oscillation data. Moreover, the values of the Bayes factor indicate that the evidence for NO is strong only when the scan is performed over the three neutrino masses with logarithmic priors; for every other combination of parameterization and prior, the preference for NO is only weak. As a by-product of our Bayesian analyses, we are able to (a) compare the Bayesian bounds on the neutrino mixing parameters to those obtained by means of frequentist approaches, finding a very good agreement; (b) determine that the lightest neutrino mass plus the two mass splittings parametrization, motivated by the physical observables, is strongly preferred over the three neutrino mass eigenstates scan and (c) find that logarithmic priors guarantee a weakly-to-moderately more efficient sampling of the parameter space. These results establish the optimal strategy to successfully explore the neutrino parameter space, based on the use of the oscillation mass splittings and a logarithmic prior on the lightest neutrino mass, when combining neutrino oscillation data with cosmology and neutrinoless double beta decay. We also show that the limits on the total neutrino mass Sigma m(nu) can change dramatically when moving from one prior to the other. These results have profound implications for future studies on the neutrino mass ordering, as they crucially state the need for self-consistent analyses which explore the best parametrization and priors, without combining results that involve different assumptions.  
  Address [Gariazzo, S.; de Salas, P. F.; Mena, O.; Ternes, C. A.; Tortola, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: gariazzo@ific.uv.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 1475-7516 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000445497200001 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3736  
Permanent link to this record
 

 
Author PTOLEMY Collaboration (Betti, M.G. et al); de Salas, P.F.; Gariazzo, S.; Pastor, S. url  doi
openurl 
  Title A design for an electromagnetic filter for precision energy measurements at the tritium endpoint Type Journal Article
  Year 2019 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.  
  Volume 106 Issue Pages 120-131  
  Keywords PTOLEMY; Relic neutrino; Cosmic Neutrino Background; CNB; Neutrino mass; Transverse drift filter  
  Abstract We present a detailed description of the electromagnetic filter for the PTOLEMY project to directly detect the Cosmic Neutrino Background (CNB). Starting with an initial estimate for the orbital magnetic moment, the higher-order drift process of E x B is configured to balance the gradient-B drift motion of the electron in such a way as to guide the trajectory into the standing voltage potential along the mid-plane of the filter. As a function of drift distance along the length of the filter, the filter zooms in with exponentially increasing precision on the transverse velocity component of the electron kinetic energy. This yields a linear dimension for the total filter length that is exceptionally compact compared to previous techniques for electromagnetic filtering. The parallel velocity component of the electron kinetic energy oscillates in an electrostatic harmonic trap as the electron drifts along the length of the filter. An analysis of the phase-space volume conservation validates the expected behavior of the filter from the adiabatic invariance of the orbital magnetic moment and energy conservation following Liouville's theorem for Hamiltonian systems. (C) 2019 Elsevier B.V. All rights reserved.  
  Address [Hochberg, Y.] Hebrew Univ Jerusalem, Racah Inst Phys, Jerusalem, Israel, Email: cgtully@Princeton.EDU  
  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 0146-6410 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000464490900003 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 3978  
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