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Author Witte, S.; Villanueva-Domingo, P.; Gariazzo, S.; Mena, O.; Palomares-Ruiz, S. url  doi
openurl 
  Title EDGES result versus CMB and low-redshift constraints on ionization histories Type Journal Article
  Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 97 Issue 10 Pages 103533 - 8pp  
  Keywords  
  Abstract We examine the results from the Experiment to Detect the Global Epoch of Reionization Signature (EDGES), which has recently claimed the detection of a strong absorption in the 21 cm hyperfine transition line of neutral hydrogen, at redshifts demarcating the early stages of star formation. More concretely, we study the compatibility of the shape of the EDGES absorption profile, centered at a redshift of z similar to 17.2, with measurements of the reionization optical depth, the Gunn-Peterson optical depth, and Lyman-alpha emission from star-forming galaxies, for a variety of possible reionization models within the standard ACDM framework (that is, a Universe with a cosmological constant. and cold dark matter CDM). When, conservatively, we only try to accommodate the location of the absorption dip, we identify a region in the parameter space of the astrophysical parameters that successfully explains all of the aforementioned observations. However, one of the most abnormal features of the EDGES measurement is the absorption amplitude, which is roughly a factor of 2 larger than the maximum allowed value in the ACDM framework. We point out that the simple considered astrophysical models that produce the largest absorption amplitudes are unable to explain the depth of the dip and of reproducing the observed shape of the absorption profile.  
  Address [Witte, Samuel; Villanueva-Domingo, Pablo; Gariazzo, Stefano; Mena, Olga; Palomares-Ruiz, Sergio] 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:000433291600010 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3606  
Permanent link to this record
 

 
Author Arguelles, C.A.; Palomares-Ruiz, S.; Schneider, A.; Wille, L.; Yuan, T.L. url  doi
openurl 
  Title Unified atmospheric neutrino passing fractions for large-scale neutrino telescopes Type Journal Article
  Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 07 Issue 7 Pages 047 - 41pp  
  Keywords neutrino detectors; neutrino experiments; ultra high energy photons and neutrinos  
  Abstract The atmospheric neutrino passing fraction, or self-veto, is defined as the probability for an atmospheric neutrino not to be accompanied by a detectable muon from the same cosmic-ray air shower. Building upon previous work, we propose a redefinition of the passing fractions by unifying the treatment for muon and electron neutrinos. Several approximations have also been removed. This enables performing detailed estimations of the uncertainties in the passing fractions from several inputs: muon losses, cosmic-ray spectrum, hadronic-interaction models and atmosphere-density profiles. We also study the passing fractions under variations of the detector configuration: depth, surrounding medium and muon veto trigger probability. The calculation exhibits excellent agreement with passing fractions obtained from Monte Carlo simulations. Finally, we provide a general software framework to implement this veto technique for all large-scale neutrino observatories.  
  Address [Arguelle, Carlos A.] MIT, Dept Phys, Cambridge, MA 02139 USA, Email: caad@mit.edu;  
  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:000439590200003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3677  
Permanent link to this record
 

 
Author Diamanti, R.; Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. url  doi
openurl 
  Title Constraining dark matter late-time energy injection: decays and p-wave annihilations Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 02 Issue 2 Pages 017 - 24pp  
  Keywords dark matter theory; CMBR theory  
  Abstract We use the latest cosmic microwave background (CMB) observations to provide updated constraints on the dark matter lifetime as well as on p-wave suppressed annihilation cross sections in the 1 MeV to 1 TeV mass range. In contrast to scenarios with an s-wave dominated annihilation cross section, which mainly affect the CMB close to the last scattering surface, signatures associated with these scenarios essentially appear at low redshifts (z less than or similar to 50) when structure began to form, and thus manifest at lower multipoles in the CMB power spectrum. We use data from Planck, WMAP9, SPT and ACT, as well as Lyman-alpha measurements of the matter temperature at z similar to 4 to set a 95% confidence level lower bound on the dark matter lifetime of similar to 4 x 10(25) s for m(chi) = 100 MeV. This bound becomes lower by an order of magnitude at m(chi) = 1 TeV due to inefficient energy deposition into the inter-galactic medium. We also show that structure formation can enhance the effect of p-wave suppressed annihilation cross sections by many orders of magnitude with respect to the background cosmological rate, although even with this enhancement, CMB constraints are not yet strong enough to reach the thermal relic value of the cross section.  
  Address [Diamanti, Roberta; Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: R.Diamanti@uva.nl;  
  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:000332711400017 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1732  
Permanent link to this record
 

 
Author Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. url  doi
openurl 
  Title Flavor Composition of the High-Energy Neutrino Events in IceCube Type Journal Article
  Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.  
  Volume 113 Issue 9 Pages 091103 - 5pp  
  Keywords  
  Abstract The IceCube experiment has recently reported the observation of 28 high-energy (> 30 TeV) neutrino events, separated into 21 showers and 7 muon tracks, consistent with an extraterrestrial origin. In this Letter, we compute the compatibility of such an observation with possible combinations of neutrino flavors with relative proportion (alpha(e:)alpha(mu):alpha tau)(circle plus). Although the 7: 21 track-to-shower ratio is naively favored for the canonical (1:1:1)(circle plus) at Earth, this is not true once the atmospheric muon and neutrino backgrounds are properly accounted for. We find that, for an astrophysical neutrino E-2 energy spectrum, (1:1:1)(circle plus). at Earth is disfavored at 81% C. L. If this proportion does not change, 6 more years of data would be needed to exclude (1:1:1)(circle plus) at Earth at 3 sigma C.L. Indeed, with the recently released 3-yr data, that flavor composition is excluded at 92% C. L. The best fit is obtained for (1:0:0)(circle plus). at Earth, which cannot be achieved from any flavor ratio at sources with averaged oscillations during propagation. If confirmed, this result would suggest either a misunderstanding of the expected background events or a misidentification of tracks as showers, or even more compellingly, some exotic physics which deviates from the standard scenario.  
  Address [Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: omena@ific.uv.es;  
  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 0031-9007 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000341292800005 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1920  
Permanent link to this record
 

 
Author Bernal, N.; Forero-Romero, J.E.; Garani, R.; Palomares-Ruiz, S. url  doi
openurl 
  Title Systematic uncertainties from halo asphericity in dark matter searches Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue 9 Pages 004 - 30pp  
  Keywords dark matter theory; dark matter simulations  
  Abstract Although commonly assumed to be spherical, dark matter halos are predicted to be non-spherical by N-body simulations and their asphericity has a potential impact on the systematic uncertainties in dark matter searches. The evaluation of these uncertainties is the main aim of this work, where we study the impact of aspherical dark matter density distributions in Milky-Way-like halos on direct and indirect searches. Using data from the large N-body cosmological simulation Bolshoi, we perform a statistical analysis and quantify the systematic uncertainties on the determination of local dark matter density and the so-called J factors for dark matter annihilations and decays from the galactic center. We find that, due to our ignorance about the extent of the non-sphericity of the Milky Way dark matter halo, systematic uncertainties can be as large as 35%, within the 95% most probable region, for a spherically averaged value for the local density of 0.3-0.4 GeV/cm(3). Similarly, systematic uncertainties on the J factors evaluated around the galactic center can be as large as 10% and 15%, within the 95% most probable region, for dark matter annihilations and decays, respectively.  
  Address [Bernal, Nicolas] Univ Estadual Paulista, Inst Fis Teor, ICTP South Amer Inst Fundamental Res, BR-01405 Sao Paulo, Brazil, Email: nicolas@ift.unesp.br;  
  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:000342642500005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1958  
Permanent link to this record
 

 
Author Farzan, Y.; Palomares-Ruiz, S. url  doi
openurl 
  Title Flavor of cosmic neutrinos preserved by ultralight dark matter Type Journal Article
  Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 99 Issue 5 Pages 051702 - 8pp  
  Keywords  
  Abstract Within the standard propagation scenario, the flavor ratios of high-energy cosmic neutrinos at neutrino telescopes are expected to be around the democratic benchmark resulting from hadronic sources, (1/3:1/3:1/3)(circle plus). We show how the coupling of neutrinos to an ultralight dark matter complex scalar field would induce an effective neutrino mass that could lead to adiabatic neutrino propagation. This would result in the preservation at the detector of the production flavor composition of neutrinos at sources. This effect could lead to flavor ratios at detectors well outside the range predicted by the standard scenario of averaged oscillations. We also present an electroweak-invariant model that would lead to the required effective interaction between neutrinos and dark matter.  
  Address [Farzan, Yasaman] Inst Res Fundamental Sci IPM, Sch Phys, POB 19395-5531, Tehran, Iran, Email: yasaman@theory.ipm.ac.ir;  
  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:000461908100001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3952  
Permanent link to this record
 

 
Author Bhattacharya, A.; Esmaili, A.; Palomares-Ruiz, S.; Sarcevic, I. url  doi
openurl 
  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 [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 Mena, O.; Palomares-Ruiz, S.; Villanueva-Domingo, P.; Witte, S.J. url  doi
openurl 
  Title Constraining the primordial black hole abundance with 21-cm cosmology Type Journal Article
  Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 100 Issue 4 Pages 043540 - 23pp  
  Keywords  
  Abstract The discoveries of a number of binary black hole mergers by LIGO and VIRGO have reinvigorated the interest that primordial black holes (PBHs) of tens of solar masses could contribute non-negligibly to the dark matter energy density. Should even a small population of PBHs with masses greater than or similar to O(M-circle dot) exist, they could profoundly impact the properties of the intergalactic medium and provide insight into novel processes at work in the early Universe. We demonstrate here that observations of the 21-cm transition in neutral hydrogen during the epochs of reionization and cosmic dawn will likely provide one of the most stringent tests of solar mass PBHs. In the context of 21-cm cosmology, PBHs give rise to three distinct observable effects: (i) the modification to the primordial power spectrum (and thus also the halo mass function) induced by Poisson noise, (ii) a uniform heating and ionization of the intergalactic medium via x-rays produced during accretion, and (iii) a local modification to the temperature and density of the ambient medium surrounding isolated PBHs. Using a four-parameter astrophysical model, we show that experiments like SKA and HERA could potentially improve upon existing constraints derived using observations of the cosmic microwave background by more than 1 order of magnitude.  
  Address [Mena, Olga; Palomares-Ruiz, Sergio; Villanueva-Domingo, Pablo; Witte, Samuel J.] 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:000483047300003 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4122  
Permanent link to this record
 

 
Author Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Villanueva-Domingo, P.; Witte, S.J. url  doi
openurl 
  Title Variations in fundamental constants at the cosmic dawn Type Journal Article
  Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 06 Issue 6 Pages 026 - 25pp  
  Keywords cosmology of theories beyond the SM; particle physics – cosmology connection; reionization  
  Abstract The observation of space-time variations in fundamental constants would provide strong evidence for the existence of new light degrees of freedom in the theory of Nature. Robustly constraining such scenarios requires exploiting observations that span different scales and probe the state of the Universe at different epochs. In the context of cosmology, both the cosmic microwave background and the Lyman-a forest have proven to be powerful tools capable of constraining variations in electromagnetism, however at the moment there do not exist cosmological probes capable of bridging the gap between recombination and reionization. In the near future, radio telescopes will attempt to measure the 21 cm transition of neutral hydrogen during the epochs of reionization and the cosmic dawn (and potentially the tail end of the dark ages); being inherently sensitive to electromagnetic phenomena, these experiments will offer a unique perspective on space-time variations of the fine-structure constant and the electron mass. We show here that large variations in these fundamental constants would produce features on the 21 cm power spectrum that may be distinguishable from astrophysical uncertainties. Furthermore, we forecast the sensitivity for the Square Kilometer Array, and show that the 21 cm power spectrum may be able to constrain variations at the level of O(10(-3)).  
  Address [Lopez-Honorez, Laura] Univ Libre Bruxelles, Serv Phys Theor, CP225, B-1050 Brussels, Belgium, Email: llopezho@ulb.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:000551875400049 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4473  
Permanent link to this record
 

 
Author Villanueva-Domingo, P.; Mena, O.; Palomares-Ruiz, S. url  doi
openurl 
  Title A Brief Review on Primordial Black Holes as Dark Matter Type Journal Article
  Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal Front. Astron. Space Sci.  
  Volume 8 Issue Pages 681084 - 10pp  
  Keywords primordial black holes; dark matter; cosmology; accretion; 21 cm cosmology; gravitational waves; cosmic microwave background; microlensing  
  Abstract Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.  
  Address [Villanueva-Domingo, Pablo; Mena, Olga; Palomares-Ruiz, Sergio] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.villanueva.domingo@gmail.com  
  Corporate Author Thesis  
  Publisher Frontiers Media Sa Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-987x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000660081700001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4852  
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