UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS

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2024-11-23 17:55
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Conference: Bucharest University Faculty of Physics 2023 Meeting


Section: Nuclear and Elementary Particles Physics


Title:
Origin and sources of ultra-high-energy cosmic rays


Authors:
Paula-Gina Isar


Affiliation:
Institute of Space Science, Bucharest-Magurele, Romania


E-mail
isar@spacescience.ro


Keywords:
cosmic rays, air showers, detection techniques, Astro-Particle Physics


Abstract:
Although cosmic rays have been discovered more than a century ago, the sources of ultra-high-energy cosmic rays (UHECRs) remain a mystery for scientists nowadays. The flux of UHECRs drops with increased energy, from one particle per km^2 per year, at about 10^18 eV, to one particle per km^2 per century, at about 10^20 eV. Moreover, charged particle cosmic rays are deflected in the their way through the other space by the powerful magnetic fields, therefore the origin of arrival directions are hard to estimate precisely. Evidence that UHECRs are of extra-galactic origin has been reported extensively in the scientific literature by large-scale cosmic ray experiments, like the Pierre Auger Observatory observing the southern sky, or the Telescope Array observing the northern sky, which are nowadays struggling to increase the event measurement statistics at the highest energies with improved detectors. The highest-energy cosmic ray events recorded so far will be introduced. Potential source candidates of UHECRs will be discussed.


References:

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Acknowledgement:
This work was supported by the Romanian Ministry of Research, Innovation and Digitization, CNCS/CCCDI UEFISCDI, grant number PN23030201/30N/2023 within the National Nucleus Program, and project number PN-III-P1-1.1-TE-2021-0924/TE57/2022, within PNCDI III.