Strange fireball as an explanation of the muon excess in Auger data

0539900 - FZÚ 2021 RIV US eng J - Journal Article
Anchordoqui, L. A. … Total 3 authors
Strange fireball as an explanation of the muon excess in Auger data.
Physical Review D. Roč. 95, č. 6 (2017), s. 1-14, č. článku 063005. ISSN 2470-0010. E-ISSN 2470-0029
Research Infrastructure: AUGER-CZ - 90038
Keywords : muon excess * fireball model
OECD category: Particles and field physics
Impact factor: 4.394, year: 2017
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevD.95.063005

We argue that ultrahigh-energy cosmic-ray collisions in Earth's atmosphere can probe the strange quark density of the nucleon. These collisions have center-of-mass energies greater than or similar to 10(4.6)A GeV, where A >= 14 is the nuclear baryon number. We hypothesize the formation of a deconfined thermal fireball which undergoes a sudden hadronization. At production the fireball has a very high matter density and consists of gluons and two flavors of light quarks (u, d). Because the fireball is formed in the baryon-rich projectile fragmentation region, the high baryochemical potential damps the production of uu and dd pairs, resulting in gluon fragmentation mainly into ss. The strange quarks then become much more abundant and upon hadronization the relative density of strange hadrons is significantly enhanced over that resulting from a hadron gas. Assuming the momentum distribution functions can be approximated by Fermi-Dirac and Bose-Einstein statistics, we estimate a kaon-to-pion ratio of about 3 and expect a similar (total) baryon-topion ratio. We show that, if this were the case, the excess of strange hadrons would suppress the fraction of energy which is transferred to decaying pi(0)'s by about 20%, yielding an similar to 40% enhancement of the muon content in atmospheric cascades, in agreement with recent data reported by the Pierre Auger Collaboration.
Permanent Link: http://hdl.handle.net/11104/0317597