| |
Records |
Links |
|
Author |
Trotta, R.; Johannesson, G.; Moskalenko, I.V.; Porter, T.A.; Ruiz de Austri, R.; Strong, A.W. |
|
| |
Title  |
Constraints on Cosmic-Ray Propagation Models from a Global Bayesian Analysis |
Type |
Journal Article |
| |
Year |
2011 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
|
| |
Volume |
729 |
Issue |
2 |
Pages |
106 - 16pp |
|
| |
Keywords |
astroparticle physics; cosmic rays; diffusion; Galaxy: general; ISM: general; methods: statistical |
|
| |
Abstract |
Research in many areas of modern physics such as, e. g., indirect searches for dark matter and particle acceleration in supernova remnant shocks rely heavily on studies of cosmic rays (CRs) and associated diffuse emissions (radio, microwave, X-rays, gamma-rays). While very detailed numerical models of CR propagation exist, a quantitative statistical analysis of such models has been so far hampered by the large computational effort that those models require. Although statistical analyses have been carried out before using semi-analytical models (where the computation is much faster), the evaluation of the results obtained from such models is difficult, as they necessarily suffer from many simplifying assumptions. The main objective of this paper is to present a working method for a full Bayesian parameter estimation for a numerical CR propagation model. For this study, we use the GALPROP code, the most advanced of its kind, which uses astrophysical information, and nuclear and particle data as inputs to self-consistently predict CRs, gamma-rays, synchrotron, and other observables. We demonstrate that a full Bayesian analysis is possible using nested sampling and Markov Chain Monte Carlo methods (implemented in the SuperBayeS code) despite the heavy computational demands of a numerical propagation code. The best-fit values of parameters found in this analysis are in agreement with previous, significantly simpler, studies also based on GALPROP. |
|
| |
Address |
[Trotta, R.] Univ London Imperial Coll Sci Technol & Med, Astrophys Grp, Blackett Lab, London SW7 2AZ, England |
|
| |
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 |
ISI:000288608700029 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
541 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
|
| |
Title |
Constraints on the origin of cosmic rays above 10^18 eV from large-scale anisotropy searches in data of the Pierre Auger Observatory |
Type |
Journal Article |
| |
Year |
2013 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
|
| |
Volume |
762 |
Issue |
1 |
Pages |
L13 - 8pp |
|
| |
Keywords |
astroparticle physics; cosmic rays |
|
| |
Abstract |
A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10(18) eV at the Pierre Auger Observatory is reported. For the first time, these large-scale anisotropy searches are performed as a function of both the right ascension and the declination and expressed in terms of dipole and quadrupole moments. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Upper limits on dipole and quadrupole amplitudes are derived under the hypothesis that any cosmic ray anisotropy is dominated by such moments in this energy range. These upper limits provide constraints on the production of cosmic rays above 10(18) eV, since they allow us to challenge an origin from stationary galactic sources densely distributed in the galactic disk and emitting predominantly light particles in all directions. |
|
| |
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 |
2041-8205 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000312488400013 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1279 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
HAWC Collaboration (Albert, A. et al); Salesa Greus, F. |
|
| |
Title |
Constraints on the Very High Energy Gamma-Ray Emission from Short GRBs with HAWC |
Type |
Journal Article |
| |
Year |
2022 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
|
| |
Volume |
936 |
Issue |
2 |
Pages |
126 - 14pp |
|
| |
Keywords |
|
|
| |
Abstract |
Many gamma-ray bursts (GRBs) have been observed from radio wavelengths, and a few at very high energies (VHEs, >100 GeV). The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is well suited to study transient phenomena at VHEs owing to its large field of view and duty cycle. These features allow for searches of VHE emission and can probe different model assumptions of duration and spectra. In this paper, we use data collected by HAWC between 2014 December and 2020 May to search for emission in the energy range from 80 to 800 GeV coming from a sample of 47 short GRBs that triggered the Fermi, Swift, and Konus satellites during this period. This analysis is optimized to search for delayed and extended VHE emission within the first 20 s of each burst. We find no evidence of VHE emission, either simultaneous or delayed, with respect to the prompt emission. Upper limits (90% confidence level) derived on the GRB fluence are used to constrain the synchrotron self-Compton forward-shock model. Constraints for the interstellar density as low as 10(-2) cm(-3) are obtained when assuming z = 0.3 for bursts with the highest keV fluences such as GRB 170206A and GRB 181222841. Such a low density makes observing VHE emission mainly from the fast-cooling regime challenging. |
|
| |
Address |
[Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.; Zhou, H.] Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA, Email: nifraija@astro.unam.mx; |
|
| |
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:000852139800001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5354 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
HAWC Collaboration (Albert, A. et al); Salesa Greus, F. |
|
| |
Title |
Detailed Analysis of the TeV gamma-Ray Sources 3HWC J1928+178, 3HWC J1930+188, and the New Source HAWC J1932+192 |
Type |
Journal Article |
| |
Year |
2023 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
|
| |
Volume |
942 |
Issue |
2 |
Pages |
96 - 18pp |
|
| |
Keywords |
|
|
| |
Abstract |
The latest High Altitude Water Cherenkov (HAWC) point-like source catalog up to 56 TeV reported the detection of two sources in the region of the Galactic plane at galactic longitude 52 degrees < l < 55 degrees, 3HWC J1930+188 and 3HWC J1928+178. The first one is associated with a known TeV source, the supernova remnant SNR G054.1+00.3. It was discovered by one of the currently operating Imaging Atmospheric Cherenkov Telescope (IACT), the Very Energetic Radiation Imaging Telescope Array System (VERITAS), detected by the High Energy Stereoscopic System (H.E.S.S), and identified as a composite SNR. However, the source 3HWC J1928+178, discovered by HAWC and coincident with the pulsar PSR J1928+1746, was not detected by any IACT despite their long exposure on the region, until a recent new analysis of H.E.S.S. data was able to confirm it. Moreover, no X-ray counterpart has been detected from this pulsar. We present a multicomponent fit of this region using the latest HAWC data. This reveals an additional new source, HAWC J1932+192, which is potentially associated with the pulsar PSR J1932+1916, whose gamma-ray emission could come from the acceleration of particles in its pulsar wind nebula. In the case of 3HWC J1928+178, several possible explanations are explored, in an attempt to unveil the origins of the very-high-energy gamma-ray emission. |
|
| |
Address |
[Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM USA, Email: armelle.jardin-blicq@mpi-hd.mpg.de; |
|
| |
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:000942614000001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5484 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Cermeño, M.; Perez-Garcia, M.A.; Lineros, R.A. |
|
| |
Title |
Enhanced neutrino emissivities in pseudoscalar-mediated dark matter annihilation in neutron stars |
Type |
Journal Article |
| |
Year |
2018 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
|
| |
Volume |
863 |
Issue |
2 |
Pages |
157 - 9pp |
|
| |
Keywords |
dark matter; neutrinos; stars: neutron |
|
| |
Abstract |
We calculate neutrino emissivities from self-annihilating dark matter (DM) (chi) in the dense and hot stellar interior of a (proto)neutron star. Using a model where DM interacts with nucleons in the stellar core through a pseudoscalar boson (a) we find that the neutrino production rates from the dominant reaction channels chi -> nu(nu) over bar or chi chi -> aa, with subsequent decay of the mediator a -> nu(nu) over bar, could locally match and even surpass those of the standard neutrinos from the modified nuclear URCA processes at early ages. We find that the emitting region can be localized in a tiny fraction of the star (less than a few percent of the core volume) and the process can last its entire lifetime for some cases under study. We discuss the possible consequences of our results for stellar cooling in light of existing DM constraints. |
|
| |
Address |
[Cermeno, M.; Perez-Garcia, M. A.] Univ Salamanca, Dept Fundamental Phys, Plaza Merced S-N, E-37008 Salamanca, Spain, Email: marinacgavilan@usal.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 |
0004-637x |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000442222700019 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
3696 |
|
| Permanent link to this record |
