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Author Pastor, S. doi  openurl
  Title Light Neutrinos in Cosmology Type Journal Article
  Year 2011 Publication Physics of Particles and Nuclei Abbreviated Journal Phys. Part. Nuclei  
  Volume 42 Issue 4 Pages 628-640  
  Keywords  
  Abstract Neutrinos can play an important role in the evolution of the Universe, modifying some of the cosmological observables. We describe how the precision of present cosmological data can be used to learn about neutrino properties, in particular their mass. We show how the analysis of current cosmological observations provides an upper bound on the sum of neutrino masses, with improved sensitivity from future cosmological measurements.  
  Address Univ Valencia, CSIC, Inst Fis Corpuscular, Ed Inst Invest, Valencia 40071, Spain  
  Corporate Author Thesis  
  Publisher Maik Nauka/Interperiodica/Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1063-7796 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000300084900011 Approved no  
  Is ISI yes International Collaboration (up) no  
  Call Number IFIC @ pastor @ Serial 906  
Permanent link to this record
 

 
Author Franca, U.; Lineros, R.A.; Palacio, J.; Pastor, S. url  doi
openurl 
  Title Probing interactions within the dark matter sector via extra radiation contributions Type Journal Article
  Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 87 Issue 12 Pages 123521 - 6pp  
  Keywords  
  Abstract The nature of dark matter is one of the most thrilling riddles for both cosmology and particle physics nowadays. While in the typical models the dark sector is composed only by weakly interacting massive particles, an arguably more natural scenario would include a whole set of gauge interactions which are invisible for the standard model but that are in contact with the dark matter. We present a method to constrain the number of massless gauge bosons and other relativistic particles that might be present in the dark sector using current and future cosmic microwave background data, and provide upper bounds on the size of the dark sector. We use the fact that the dark matter abundance depends on the strength of the interactions with both sectors, which allows one to relate the freeze-out temperature of the dark matter with the temperature of this cosmic background of dark gauge bosons. This relation can then be used to calculate how sizable is the impact of the relativistic dark sector in the number of degrees of freedom of the early Universe, providing an interesting and testable connection between cosmological data and direct/indirect detection experiments. The recent Planck data, in combination with other cosmic microwave background experiments and baryonic acoustic oscillations data, constrains the number of relativistic dark gauge bosons, when the freeze-out temperature of the dark matter is larger than the top mass, to be N less than or similar to 14 for the simplest scenarios, while those limits are slightly relaxed for the combination with the Hubble constant measurements to N less than or similar to 20. Future releases of Planck data are expected to reduce the uncertainty by approximately a factor of 3, which will reduce significantly the parameter space of allowed models.  
  Address [Franca, Urbano; Lineros, Roberto A.; Palacio, Joaquim; Pastor, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia 46071, 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 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000320765300005 Approved no  
  Is ISI yes International Collaboration (up) no  
  Call Number IFIC @ pastor @ Serial 1487  
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Author de Salas, P.F.; Pastor, S. url  doi
openurl 
  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 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:000381830000052 Approved no  
  Is ISI yes International Collaboration (up) no  
  Call Number IFIC @ pastor @ Serial 2784  
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Author Mangano, G.; Miele, G.; Pastor, S.; Pisanti, O.; Sarikas, S. url  doi
openurl 
  Title Constraining the cosmic radiation density due to lepton number with Big Bang Nucleosynthesis Type Journal Article
  Year 2011 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 03 Issue 3 Pages 035 - 18pp  
  Keywords big bang nucleosynthesis; neutrino properties; cosmological neutrinos; physics of the early universe  
  Abstract The cosmic energy density in the form of radiation before and during Big Bang Nucleosynthesis (BBN) is typically parameterized in terms of the effective number of neutrinos N-eff. This quantity, in case of no extra degrees of freedom, depends upon the chemical potential and the temperature characterizing the three active neutrino distributions, as well as by their possible non-thermal features. In the present analysis we determine the upper bounds that BBN places on N-eff from primordial neutrino-antineutrino asymmetries, with a careful treatment of the dynamics of neutrino oscillations. We consider quite a wide range for the total lepton number in the neutrino sector, eta(nu) = eta(nu e) + eta(nu mu) + eta(nu tau) and the initial electron neutrino asymmetry eta(in)(nu e), solving the corresponding kinetic equations which rule the dynamics of neutrino (antineutrino) distributions in phase space due to collisions, pair processes and flavor oscillations. New bounds on both the total lepton number in the neutrino sector and the nu(e)-(nu) over bar (e) asymmetry at the onset of BBN are obtained fully exploiting the time evolution of neutrino distributions, as well as the most recent determinations of primordial H-2/H density ratio and He-4 mass fraction. Note that taking the baryon fraction as measured by WMAP, the H-2/H abundance plays a relevant role in constraining the allowed regions in the eta(nu)-eta(in)(nu e) plane. These bounds fix the maximum contribution of neutrinos with primordial asymmetries to N-eff as a function of the mixing parameter theta(13), and point out the upper bound N-eff less than or similar to 3.4. Comparing these results with the forthcoming measurement of N-eff by the Planck satellite will likely provide insight on the nature of the radiation content of the universe.  
  Address [Mangano, Gianpiero; Miele, Gennaro; Pisanti, Ofelia; Sarikas, Srdjan] Ist Nazl Fis Nucl, Sez Napoli, I-80126 Naples, Italy, Email: mangano@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 ISI:000291258300035 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ elepoucu @ Serial 642  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. url  doi
openurl 
  Title Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter Type Journal Article
  Year 2010 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 5 Pages 314-326  
  Keywords Cosmic rays; UHECR; Anisotropy; Pierre Auger Observatory; Extra-galactic; GZK  
  Abstract Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, 6 x 10(19) eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1 degrees from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38(-6)(+7))%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69-(+11)(13))%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.  
  Address [Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina  
  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 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284669100007 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ elepoucu @ Serial 320  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. doi  openurl
  Title The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays Type Journal Article
  Year 2011 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 6 Issue Pages P01003 - 16pp  
  Keywords Cherenkov detectors; Large detector systems for particle and astroparticle physics; Particle detectors  
  Abstract Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.  
  Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] LIP, P-1000 Lisbon, Portugal  
  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 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000291345600003 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 646  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. url  doi
openurl 
  Title The fluorescence detector of the Pierre Auger Observatory Type Journal Article
  Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 620 Issue 2-3 Pages 227-251  
  Keywords Cosmic rays; Fluorescence detector  
  Abstract The Pierre Auger Observatory is a hybrid detector for ultra-high energy cosmic rays. It combines a surface array to measure secondary particles at ground level together with a fluorescence detector to measure the development of air showers in the atmosphere above the array. The fluorescence detector comprises 24 large telescopes specialized for measuring the nitrogen fluorescence caused by charged particles of cosmic ray air showers. In this paper we describe the components of the fluorescence detector including its optical system, the design of the camera, the electronics, and the systems for relative and absolute calibration. We also discuss the operation and the monitoring of the detector. Finally, we evaluate the detector performance and precision of shower reconstructions.  
  Address [Bohacova, M.; Chudoba, J.; Grygar, J.; Hrabovsky, M.; Karova, T.; Mandat, D.; Necesal, P.; Nozka, L.; Nyklicek, M.; Palatka, M.; Pech, M.; Prouza, M.; Ridky, J.; Schovancova, J.; Schovanek, P.; Travnicek, P.] Acad Sci Czech Republic, Inst Phys, Prague, Czech Republic, Email: prouza@fzu.cz  
  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 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000280601700018 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ elepoucu @ Serial 400  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. url  doi
openurl 
  Title The exposure of the hybrid detector of the Pierre Auger Observatory Type Journal Article
  Year 2011 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 6 Pages 368-381  
  Keywords Ultra high energy cosmic rays; Pierre Auger Observatory; Extensive air showers; Trigger; Exposure; Fluorescence detector; Hybrid  
  Abstract The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The “hybrid” detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.  
  Address [Ave, M.; Bluemer, H.; Daumiller, K.; Dembinski, H.; Engel, R.; Garrido, X.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Mueller, S.; Oehlschlaeger, J.; Pierog, T.; Roth, M.; Salamida, F.; Schieler, H.; Schroeder, F.; Schuessler, F.; Smida, R.; Ulrich, R.; Unger, M.; Valino, I.; Weinidl, A.; Will, M.; Wommer, M.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany, Email: francesco.salamida@kit.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 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000287068800007 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ pastor @ Serial 580  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. url  doi
openurl 
  Title Measurement of the energy spectrum of cosmic rays above 10(18) eV using the Pierre Auger Observatory Type Journal Article
  Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 685 Issue 4-5 Pages 239-246  
  Keywords Pierre Auger Observatory; Cosmic rays; Energy spectrum  
  Abstract We report a measurement of the flux of cosmic rays with unprecedented precision and Statistics using the Pierre Auger Observatory Based on fluorescence observations in coincidence with at least one Surface detector we derive a spectrum for energies above 10(18) eV We also update the previously published energy spectrum obtained with the surface detector array The two spectra are combined addressing the systematic uncertainties and, in particular. the influence of the energy resolution on the spectral shape The spectrum can be described by a broken power law E-gamma with index gamma = 3 3 below the ankle which is measured at log(10)(E-ankle/eV) = 18 6 Above the ankle the spectrum is described by a power law with index 2 6 followed by a flux suppression, above about log(10)(E/eV) = 19 5, detected with high statistical significance.  
  Address [Ave, M.; Bluemer, H.; Daumiller, K.; Engel, R.; Garrido, X.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Mueller, S.; Oehlschlaeger, J.; Pierog, T.; Roth, M.; Salamida, F.; Schieler, H.; Schroeder, F.; Schuessler, F.; Smida, R.; Ulrich, R.; Unger, M.; Valino, I.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany  
  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 ISI:000275640600003 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ elepoucu @ Serial 480  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. url  doi
openurl 
  Title A study of the effect of molecular and aerosol conditions in the atmosphere on air fluorescence measurements at the Pierre Auger Observatory Type Journal Article
  Year 2010 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 33 Issue 2 Pages 108-129  
  Keywords Cosmic rays; Extensive air showers; Air fluorescence method; Atmosphere; Aerosols; Lidar; Bi-static lidar  
  Abstract The air fluorescence detector of the Pierre Auger Observatory is designed to perforin calorimetric measurements of extensive air showers created by Cosmic rays of above 10(18) eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group Of monitoring instruments to record atmospheric conditions across the detector site, ail area exceeding 3000 km(2). The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierre Auger Observatory since the start of regular operations in 2004, and includes a discussion of the impact of these measurements oil air shower reconstructions. Between 10(18) and 10(20) eV, the systematic Uncertainties due to all atmospheric effects increase from 4% to 8% in measurements of shower energy, and 4 g cm(-2) to 8 g cm(-2) in measurements of the shower maximum.  
  Address [BenZvi, S.; Pfendner, C.; Westerhoff, S.] Univ Wisconsin, Madison, WI 53706 USA, Email: sybenzvi@icecube.wisc.cdu  
  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 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000275514800007 Approved no  
  Is ISI yes International Collaboration (up) yes  
  Call Number IFIC @ elepoucu @ Serial 486  
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