Mass composition of ultrahigh-energy cosmic rays with the Telescope Array Surface Detector data

0502252 - FZÚ 2020 RIV US eng J - Journal Article
Abbasi, R.U. - Abe, M. - Abu-Zayyad, T. - Urban, Federico … Total 143 authors
Mass composition of ultrahigh-energy cosmic rays with the Telescope Array Surface Detector data.
Physical Review D. Roč. 98, č. 2 (2019), s. 1-11, č. článku 022002. ISSN 2470-0010. E-ISSN 2470-0029
R&D Projects: GA MŠMT EF15_003/0000437
Grant - others:OP VVV - CoGraDS(XE) CZ.02.1.01/0.0/0.0/15_003/0000437
Institutional support: RVO:68378271
Keywords : ultra-high-energy cosmic arrays * telescope array * mass composition * boosted decision trees
OECD category: Particles and field physics
Impact factor: 4.833, year: 2019
Method of publishing: Limited access
https://doi.org/10.1103/physrevd.99.022002

The results on ultrahigh-energy cosmic rays (UHECR) mass composition obtained with the Telescope Array surface detector are presented. The analysis employs the Boosted Decision tree (BDT) multivariate analysis built upon 14 observables related to both the properties of the shower front and the lateral distribution function. The multivariate classifier is trained with Monte-Carlo sets of events induced by the primary protons and iron. An average atomic mass of UHECR is presented for energies 1018.0 – 1020.0 eV. The average atomic mass of primary particles shows no significant energy dependence and corresponds to ⟨ln A⟩ = 2.0 ± 0.1(stat.) ± 0.44(syst.). The result is compared to the mass composition obtained by the Telescope Array with Xmax technique along with the results of other experiments. Possible systematic errors of the method are discussed.

Permanent Link: http://hdl.handle.net/11104/0294201