A scenario for the Galactic cosmic rays between the knee and the second-knee
We perform a fit to measurements of the cosmic ray spectrum in the energy range between 10 15 eV and 10 18 eV using data from the TALE, Tunka and Auger experiments. We also fit the data on the depth of shower maximum, X max , from Tunka and Yakutsk or from Auger to constrain the cosmic ray compositi...
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ftconicet:oai:ri.conicet.gov.ar:11336/124865 2023-10-09T21:56:27+02:00 A scenario for the Galactic cosmic rays between the knee and the second-knee Mollerach, Maria Silvia Roulet, Esteban application/pdf http://hdl.handle.net/11336/124865 eng eng IOP Publishing info:eu-repo/semantics/altIdentifier/url/http://stacks.iop.org/1475-7516/2019/i=03/a=017?key=crossref.4d373d5517aab5ac9ab06654cef3cb5f info:eu-repo/semantics/altIdentifier/doi/10.1088/1475-7516/2019/03/017 http://hdl.handle.net/11336/124865 Mollerach, Maria Silvia; Roulet, Esteban; A scenario for the Galactic cosmic rays between the knee and the second-knee; IOP Publishing; Journal of Cosmology and Astroparticle Physics; 2019; 3; 7-3-2019; 1-17 1475-7516 CONICET Digital CONICET info:eu-repo/semantics/restrictedAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ COSMIC RAY THEORY ULTRA HIGH ENERGY COSMIC RAYS https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion ftconicet https://doi.org/10.1088/1475-7516/2019/03/017 2023-09-24T19:21:22Z We perform a fit to measurements of the cosmic ray spectrum in the energy range between 10 15 eV and 10 18 eV using data from the TALE, Tunka and Auger experiments. We also fit the data on the depth of shower maximum, X max , from Tunka and Yakutsk or from Auger to constrain the cosmic ray composition. We consider a Galactic component that is a mixture of five representative nuclear species (H, He, N, Si and Fe), for which we adopt rigidity dependent broken power-law spectra, and we allow for an extragalactic component which becomes strongly suppressed for decreasing energies. The relative abundances of the Galactic components at 10 15 eV are taken to be comparable to those determined by direct measurements at 10 13 eV. The main features of the spectrum and of the composition are reproduced in these scenarios. The spectral knee results from the break of the H spectrum at E k 3× 10 15 eV, although it is broadened by the comparable contribution from He which has a break at about 6× 10 15 eV. The low-energy ankle at E la 2× 10 16 eV coincides with the strong suppression of the H and He Galactic components and the increasing relative contribution of the heavier ones, but the observed hardening of the spectrum at this energy turns out to result from the growing contribution of the extragalactic component. The second-knee at E sk 26 E k 8× 10 16 eV is associated with the steepening of the Galactic Fe component. The transition to the regime in which the total cosmic ray flux is dominated by the extragalactic component takes place at an energy of about 10 17 eV. The parameters of the fit depend on the specific X max dataset that is considered, with the Yakutsk and Tunka data leading to a suppression of the light components being steeper beyond the knee so as to allow a faster growth of the average mass around the low-energy ankle. The results also depend on the hadronic model that is used to interpret X max measurements and we compare the parameters obtained with Sibyll 2.3, EPOS-LHC and QGSJET II-04. The impact of the ... Article in Journal/Newspaper Yakutsk CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) Yakutsk Journal of Cosmology and Astroparticle Physics 2019 03 017 017 |
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Open Polar |
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CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) |
op_collection_id |
ftconicet |
language |
English |
topic |
COSMIC RAY THEORY ULTRA HIGH ENERGY COSMIC RAYS https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
spellingShingle |
COSMIC RAY THEORY ULTRA HIGH ENERGY COSMIC RAYS https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 Mollerach, Maria Silvia Roulet, Esteban A scenario for the Galactic cosmic rays between the knee and the second-knee |
topic_facet |
COSMIC RAY THEORY ULTRA HIGH ENERGY COSMIC RAYS https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
description |
We perform a fit to measurements of the cosmic ray spectrum in the energy range between 10 15 eV and 10 18 eV using data from the TALE, Tunka and Auger experiments. We also fit the data on the depth of shower maximum, X max , from Tunka and Yakutsk or from Auger to constrain the cosmic ray composition. We consider a Galactic component that is a mixture of five representative nuclear species (H, He, N, Si and Fe), for which we adopt rigidity dependent broken power-law spectra, and we allow for an extragalactic component which becomes strongly suppressed for decreasing energies. The relative abundances of the Galactic components at 10 15 eV are taken to be comparable to those determined by direct measurements at 10 13 eV. The main features of the spectrum and of the composition are reproduced in these scenarios. The spectral knee results from the break of the H spectrum at E k 3× 10 15 eV, although it is broadened by the comparable contribution from He which has a break at about 6× 10 15 eV. The low-energy ankle at E la 2× 10 16 eV coincides with the strong suppression of the H and He Galactic components and the increasing relative contribution of the heavier ones, but the observed hardening of the spectrum at this energy turns out to result from the growing contribution of the extragalactic component. The second-knee at E sk 26 E k 8× 10 16 eV is associated with the steepening of the Galactic Fe component. The transition to the regime in which the total cosmic ray flux is dominated by the extragalactic component takes place at an energy of about 10 17 eV. The parameters of the fit depend on the specific X max dataset that is considered, with the Yakutsk and Tunka data leading to a suppression of the light components being steeper beyond the knee so as to allow a faster growth of the average mass around the low-energy ankle. The results also depend on the hadronic model that is used to interpret X max measurements and we compare the parameters obtained with Sibyll 2.3, EPOS-LHC and QGSJET II-04. The impact of the ... |
format |
Article in Journal/Newspaper |
author |
Mollerach, Maria Silvia Roulet, Esteban |
author_facet |
Mollerach, Maria Silvia Roulet, Esteban |
author_sort |
Mollerach, Maria Silvia |
title |
A scenario for the Galactic cosmic rays between the knee and the second-knee |
title_short |
A scenario for the Galactic cosmic rays between the knee and the second-knee |
title_full |
A scenario for the Galactic cosmic rays between the knee and the second-knee |
title_fullStr |
A scenario for the Galactic cosmic rays between the knee and the second-knee |
title_full_unstemmed |
A scenario for the Galactic cosmic rays between the knee and the second-knee |
title_sort |
scenario for the galactic cosmic rays between the knee and the second-knee |
publisher |
IOP Publishing |
url |
http://hdl.handle.net/11336/124865 |
geographic |
Yakutsk |
geographic_facet |
Yakutsk |
genre |
Yakutsk |
genre_facet |
Yakutsk |
op_relation |
info:eu-repo/semantics/altIdentifier/url/http://stacks.iop.org/1475-7516/2019/i=03/a=017?key=crossref.4d373d5517aab5ac9ab06654cef3cb5f info:eu-repo/semantics/altIdentifier/doi/10.1088/1475-7516/2019/03/017 http://hdl.handle.net/11336/124865 Mollerach, Maria Silvia; Roulet, Esteban; A scenario for the Galactic cosmic rays between the knee and the second-knee; IOP Publishing; Journal of Cosmology and Astroparticle Physics; 2019; 3; 7-3-2019; 1-17 1475-7516 CONICET Digital CONICET |
op_rights |
info:eu-repo/semantics/restrictedAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
op_doi |
https://doi.org/10.1088/1475-7516/2019/03/017 |
container_title |
Journal of Cosmology and Astroparticle Physics |
container_volume |
2019 |
container_issue |
03 |
container_start_page |
017 |
op_container_end_page |
017 |
_version_ |
1779321205942124544 |