Records |
Author |
Johannesson, G.; Ruiz de Austri, R.; Vincent, A.C.; Moskalenko, I.V.; Orlando, E.; Porter, T.A.; Strong, A.W.; Trotta, R.; Feroz, F.; Graff, P.; Hobson, M.P. |
Title |
Bayesian analysis of cosmic-ray propagation: evidence against homogeneous diffusion |
Type |
Journal Article |
Year |
2016 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
Volume |
824 |
Issue |
1 |
Pages |
16 - 19pp |
Keywords |
astroparticle physics; cosmic rays; diffusion; Galaxy: general; ISM: general; methods: statistical |
Abstract |
We present the results of the most complete scan of the parameter space for cosmic ray (CR) injection and propagation. We perform a Bayesian search of the main GALPROP parameters, using the MultiNest nested sampling algorithm, augmented by the BAMBI neural network machine-learning package. This is the first study to separate out low-mass isotopes (p, (p) over bar and He) from the usual light elements (Be, B, C, N, and O). We find that the propagation parameters that best-fit p, (p) over bar, and He data are significantly different from those that fit light elements, including the B/C and Be-10/Be-9 secondary-to-primary ratios normally used to calibrate propagation parameters. This suggests that each set of species is probing a very different interstellar medium, and that the standard approach of calibrating propagation parameters using B/C can lead to incorrect results. We present posterior distributions and best-fit parameters for propagation of both sets of nuclei, as well as for the injection abundances of elements from H to Si. The input GALDEF files with these new parameters will be included in an upcoming public GALPROP update. |
Address |
[Johannesson, G.] Univ Iceland, Inst Sci, Dunhaga 3, IS-107 Reykjavik, Iceland |
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 |
0004-637x |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000377937300016 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2727 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
Title |
A search for point sources of EeV photons |
Type |
Journal Article |
Year |
2014 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
Volume |
789 |
Issue |
2 |
Pages |
160 - 12pp |
Keywords |
astroparticle physics; cosmic rays; methods: data analysis |
Abstract |
Measurements of air showers made using the hybrid technique developed with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for point sources of EeV photons anywhere in the exposed sky. A multivariate analysis reduces the background of hadronic cosmic rays. The search is sensitive to a declination band from -85 degrees to +20 degrees, in an energy range from 10(17.3) eV to 10(18.5) eV. No photon point source has been detected. An upper limit on the photon flux has been derived for every direction. The mean value of the energy flux limit that results from this, assuming a photon spectral index of -2, is 0.06 eV cm(-2) s(-1), and no celestial direction exceeds 0.25 eV cm(-2) s(-1). These upper limits constrain scenarios in which EeV cosmic ray protons are emitted by non-transient sources in the Galaxy. |
Address |
[Aab, A.; Buchholz, P.; Erfani, M.; Froehlich, U.; Heimann, P.; Homola, P.; Kuempel, D.; Niechciol, M.; Ochilo, L.; Risse, M.; Yushkov, A.; Ziolkowski, M.] Univ Siegen, D-57068 Siegen, Germany |
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 |
0004-637x |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000338674900069 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1842 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
Title |
Origin of atmospheric aerosols at the Pierre Auger Observatory using studies of air mass trajectories in South America |
Type |
Journal Article |
Year |
2014 |
Publication |
Atmospheric Research |
Abbreviated Journal |
Atmos. Res. |
Volume |
149 |
Issue |
|
Pages |
120-135 |
Keywords |
Cosmic ray; Aerosol; Air masses; Atmospheric effect; HYSPLIT; GDAS |
Abstract |
The Pierre Auger Observatory is making significant contributions towards understanding the nature and origin of ultra-high energy cosmic rays. One of its main challenges is the monitoring of the atmosphere, both in terms of its state variables and its optical properties. The aim of this work is to analyse aerosol optical depth tau(a)(z) values measured from 2004 to 2012 at the observatory, which is located in a remote and relatively unstudied area of Pampa Amarilla, Argentina. The aerosol optical depth is in average quite low – annual mean tau(a)(3.5 km) similar to 0.04 – and shows a seasonal trend with a winter minimum – tau(a)(3.5 km) – 0.03 -, and a summer maximum – tau(a)(3.5 km) similar to 0.06 -, and an unexpected increase from August to September tau(a)(35 km) similar to 0.055. We computed backward trajectories for the years 2005 to 2012 to interpret the air mass origin. Winter nights with low aerosol concentrations show air masses originating from the Pacific Ocean. Average concentrations are affected by continental sources (wind-blown dust and urban pollution), whilst the peak observed in September and October could be linked to biomass burning in the northern part of Argentina or air pollution coming from surrounding urban areas. |
Address |
[Pierre Auger Collaborat] Observ Pierre Auger, RA-5613 Malargue, Argentina |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science Inc |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0169-8095 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000341468100011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1916 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
Identifying clouds over the Pierre Auger Observatory using infrared satellite data |
Type |
Journal Article |
Year |
2013 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
50-52 |
Issue |
|
Pages |
92-101 |
Keywords |
Ultra-high energy cosmic rays; Pierre Auger Observatory; Extensive air showers; Atmospheric monitoring; Clouds; Satellites |
Abstract |
We describe a new method of identifying night-time clouds over the Pierre Auger Observatory using infrared data from the Imager instruments on the GOES-12 and GOES-13 satellites. We compare cloud. identifications resulting from our method to those obtained by the Central Laser Facility of the Auger Observatory. Using our new method we can now develop cloud probability maps for the 3000 km(2) of the Pierre Auger Observatory twice per hour with a spatial resolution of similar to 2.4 km by similar to 5.5 km. Our method could also be applied to monitor cloud cover for other ground-based observatories and for space-based observatories. |
Address |
[Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.; Sidelnik, I.] 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 |
WOS:000329271000011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1690 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
A search for point sources of EeV neutrons |
Type |
Journal Article |
Year |
2012 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
Volume |
760 |
Issue |
2 |
Pages |
148 - 11pp |
Keywords |
cosmic rays; Galaxy: disk; methods: data analysis |
Abstract |
A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 degrees to +15 degrees in declination using four different energy ranges above 1 EeV (10(18) eV). The method used in this search is more sensitive to neutrons than to photons. The upper limit on a neutron flux is derived for a dense grid of directions for each of the four energy ranges. These results constrain scenarios for the production of ultrahigh energy cosmic rays in the Galaxy. |
Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, 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 |
0004-637x |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000311217000052 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1218 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
04 |
Issue |
4 |
Pages |
040 - 21pp |
Keywords |
ultra high energy cosmic rays; cosmic ray experiments |
Abstract |
Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays. |
Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadana, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, P-1100 Lisbon, Portugal, Email: auger_spokesperson@fnal.gov |
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:000303665000040 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1015 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS) |
Type |
Journal Article |
Year |
2012 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
35 |
Issue |
9 |
Pages |
591-607 |
Keywords |
Cosmic rays; Extensive air showers; Atmospheric monitoring; Atmospheric models |
Abstract |
Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargue and averaged monthly models, the utility of the GDAS data is shown. |
Address |
[Baeuml, J.; Bluemer, H.; Daumiller, K.; Engel, R.; Gonzalez, J. G.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Maurel, D.; Oehlschlaeger, J.; Pierog, T.; Porcelli, A.; Roth, M.; Schieler, H.; Schroeder, F.; Smida, R.; Szuba, M.; Ulrich, R.; Unger, M.; Weindl, A.; Werner, F.; Will, M.; Wommer, M.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany, Email: bianca.keilhauer@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 |
WOS:000302109200006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
965 |
Permanent link to this record |
|
|
|
Author |
Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. |
Title |
Trigger and aperture of the surface detector array 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 |
613 |
Issue |
1 |
Pages |
29-39 |
Keywords |
Ultra high energy cosmic rays; Auger Observatory; Extensive air showers; Trigger; Exposure |
Abstract |
The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive air showers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the identification of candidate showers at the level of a single detector, amongst a large background (mainly random single cosmic ray muons), up to the selection of real events and the rejection of random coincidences. Such trigger makes the surface detector array fully efficient for the detection of EAS with energy above 3 x 10(18) eV, for all zenith angles between 0 degrees and 60 degrees, independently of the position of the impact point and of the mass of the primary particle. In these range of energies and angles, the exposure of the surface array can be determined purely on the basis of the geometrical acceptance. |
Address |
[Boncioli, D.; Delle Fratte, C.; Di Giulio, C.; Matthiae, G.; Petrinca, P.; Salina, G.; Verzi, V.] Univ Roma Tor Vergata, I-00173 Rome, Italy, Email: giorgio.matthiae@roma2.infn.it |
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:000274772800005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
499 |
Permanent link to this record |
|
|
|
Author |
Fornengo, N.; Lineros, R.A.; Regis, M.; Taoso, M. |
Title |
Galactic synchrotron emission from WIMPs at radio frequencies |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
01 |
Issue |
1 |
Pages |
005 - 25pp |
Keywords |
dark matter theory; cosmic ray theory; absorption and radiation processes |
Abstract |
Dark matter annihilations in the Galactic halo inject relativistic electrons and positrons which in turn generate a synchrotron radiation when interacting with the galactic magnetic field. We calculate the synchrotron flux for various dark matter annihilation channels, masses, and astrophysical assumptions in the low-frequency range and compare our results with radio surveys from 22 MHz to 1420 MHz. We find that current observations are able to constrain particle dark matter with “thermal” annihilation cross-sections, i.e. (sigma v) = 3 x 10(-26) cm(3) s(-1); and masses M-DM less than or similar to 10 GeV. We discuss the dependence of these bounds on the astrophysical assumptions, namely galactic dark matter distribution, cosmic rays propagation parameters, and structure of the galactic magnetic field. Prospects for detection in future radio surveys are outlined. |
Address |
[Fornengo, Nicolao; Regis, Marco] Univ Turin, Dipartimento Fis Teor, Ist Nazl Fis Nucl, I-10125 Turin, Italy, Email: fornengo@to.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 |
WOS:000300403300005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
939 |
Permanent link to this record |
|
|
|
Author |
ANTARES Collaboration (Adrian-Martinez, S. et al); Aguilar, J.A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Ruiz-Rivas, J.; Salesa, F.; Sanchez-Losa, A.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. |
Title |
First Search For Point Sources Of High-Energy Cosmic Neutrinos With The Antares Neutrino Telescope |
Type |
Journal Article |
Year |
2011 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
Volume |
743 |
Issue |
1 |
Pages |
L14 - 6pp |
Keywords |
astroparticle physics; cosmic rays; neutrinos |
Abstract |
Results are presented of a search for cosmic sources of high-energy neutrinos with the ANTARES neutrino telescope. The data were collected during 2007 and 2008 using detector configurations containing between 5 and 12 detection lines. The integrated live time of the analyzed data is 304 days. Muon tracks are reconstructed using a likelihood-based algorithm. Studies of the detector timing indicate a median angular resolution of 0.5 +/- 0.1 deg. The neutrino flux sensitivity is 7.5 x 10(-8)(E(v)/GeV)(-2) GeV(-1) s(-1) cm(-2) for the part of the sky that is always visible (delta < -48 deg), which is better than limits obtained by previous experiments. No cosmic neutrino sources have been observed. |
Address |
[Adrian-Martinez, S.; Ardid, M.; Bou-Cabo, M.; Camarena, F.; Ferri, M.; Larosa, G.; Martinez-Mora, J. A.] Univ Politecn Valencia, Inst Invest Gestio Integrada Zones Costaneres IGI, Gandia 46730, Spain |
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 |
2041-8205 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000297372600014 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
826 |
Permanent link to this record |