Measurement of the proton-air cross-section at $\sqrt{s}=57$ TeV with the Pierre Auger Observatory

• Published in: Physical review letters Vol. 109; no. 6
• Main Authors: Abreu, P., Avenier, M., Bérat, C., Chauvin, J., Koang, D.H., Le Coz, S., Lebrun, D., Louedec, K., Montanet, F., Stutz, A., Tartare, M., Bellétoile, A., Dallier, Richard, Lautridou, Pascal, Marin, V., Martin, Lilian, Ravel, O., Revenu, Benoît, Allard, D., Creusot, A., Decerprit, G., Lachaud, C., Parizot, E., Tristram, G., Bardenet, R., Cordier, A., Dagoret-Campagne, S., Garcia Gamez, D., Kégl, Balázs, Monnier Ragaigne, D., Urban, Martin
• Format: Journal Article
• Language: English
• Published: United States American Physical Society 02-07-2012
• Subjects: Astrophysics; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISTRIBUTION; High Energy Astrophysical Phenomena; High Energy Physics - Experiment; NUCLEONS; PARTICLE PRODUCTION; Physics; Sciences of the Universe
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.109.062002

We report a measurement of the proton-air cross-section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analysing the tail of the distribution of the shower maxima, a proton-air cross-section of $[505\pm22(stat)^{+28}_{-36}(sys)]$ mb is found.