Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory
In this work we present a combined fit of the energy spectrum and mass composition data above 6×1017 eV as measured by the Pierre Auger Collaboration and we show that our data can be reproduced by the superposition of two (or more) components, either Galactic or extragalactic. We use a simple astrop...
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| Format: | Article |
| Language: | English |
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EDP Sciences
2023-01-01
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| Series: | EPJ Web of Conferences |
| Online Access: | https://www.epj-conferences.org/articles/epjconf/pdf/2023/09/epjconf_uhecr2023_02013.pdf |
| _version_ | 1797807720881979392 |
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| author | Guido Eleonora |
| author_facet | Guido Eleonora |
| author_sort | Guido Eleonora |
| collection | DOAJ |
| description | In this work we present a combined fit of the energy spectrum and mass composition data above 6×1017 eV as measured by the Pierre Auger Collaboration and we show that our data can be reproduced by the superposition of two (or more) components, either Galactic or extragalactic. We use a simple astrophysical model with two extragalactic components, one dominant at high energy and the other at low energy, whose superposition generates the so-called “ankle” feature. We find that the component dominating the low (high) energy region is required to be emitted from the sources with a very soft (hard) spectrum. In our best fit scenario the sources contributing above the ankle emit a mixed and increasingly heavier mass composition, whereas a mix of protons and intermediate-mass nuclei is observed below the ankle, which reach the Earth almost una↵ected by the propagation in the intergalactic space. The possible presence of a Galactic population providing the intermediate-mass contribution at low energy is also explored.
In order to evaluate our capability to constrain astrophysical models, we finally discuss the impact on the fit results of the main experimental systematic uncertainties and of the assumptions on the quantities a↵ecting propagation, both in the atmosphere and in the intergalactic medium. |
| first_indexed | 2024-03-13T06:26:52Z |
| format | Article |
| id | doaj.art-7373fa17bec249eeaa146d65a9ad4b47 |
| institution | Directory Open Access Journal |
| issn | 2100-014X |
| language | English |
| last_indexed | 2024-03-13T06:26:52Z |
| publishDate | 2023-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | EPJ Web of Conferences |
| spelling | doaj.art-7373fa17bec249eeaa146d65a9ad4b472023-06-09T09:15:58ZengEDP SciencesEPJ Web of Conferences2100-014X2023-01-012830201310.1051/epjconf/202328302013epjconf_uhecr2023_02013Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger ObservatoryGuido Eleonora0Department für Physik, Universität SiegenIn this work we present a combined fit of the energy spectrum and mass composition data above 6×1017 eV as measured by the Pierre Auger Collaboration and we show that our data can be reproduced by the superposition of two (or more) components, either Galactic or extragalactic. We use a simple astrophysical model with two extragalactic components, one dominant at high energy and the other at low energy, whose superposition generates the so-called “ankle” feature. We find that the component dominating the low (high) energy region is required to be emitted from the sources with a very soft (hard) spectrum. In our best fit scenario the sources contributing above the ankle emit a mixed and increasingly heavier mass composition, whereas a mix of protons and intermediate-mass nuclei is observed below the ankle, which reach the Earth almost una↵ected by the propagation in the intergalactic space. The possible presence of a Galactic population providing the intermediate-mass contribution at low energy is also explored. In order to evaluate our capability to constrain astrophysical models, we finally discuss the impact on the fit results of the main experimental systematic uncertainties and of the assumptions on the quantities a↵ecting propagation, both in the atmosphere and in the intergalactic medium.https://www.epj-conferences.org/articles/epjconf/pdf/2023/09/epjconf_uhecr2023_02013.pdf |
| spellingShingle | Guido Eleonora Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory EPJ Web of Conferences |
| title | Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory |
| title_full | Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory |
| title_fullStr | Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory |
| title_full_unstemmed | Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory |
| title_short | Interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the Pierre Auger Observatory |
| title_sort | interpreting the cosmic ray spectrum and composition measurements across the ankle and up to the highest energies with the data of the pierre auger observatory |
| url | https://www.epj-conferences.org/articles/epjconf/pdf/2023/09/epjconf_uhecr2023_02013.pdf |
| work_keys_str_mv | AT guidoeleonora interpretingthecosmicrayspectrumandcompositionmeasurementsacrosstheankleanduptothehighestenergieswiththedataofthepierreaugerobservatory |