July 29, 2015 to August 6, 2015
World Forum
Europe/Amsterdam timezone

Telescope Array measurement of UHECR composition from stereoscopic fluorescence detection

Jul 30, 2015, 3:30 PM
Amazon Foyer (World Forum)

Amazon Foyer

World Forum

Churchillplein 10 2517 JW Den Haag The Netherlands
Board: 229
Poster contribution CR-EX Poster 1 CR


Dr Thomas Stroman (University of Utah) Dr Yuichiro Tameda (Institute for Cosmic Ray Research, University of Tokyo)


The chemical composition of ultra-high-energy cosmic rays (UHECRs) affects the observable distribution of air-shower $X_{\rm max}$ values, the atmospheric slant depth at which the number of secondary shower particles reaches its maximum. The observed $X_{\rm max}$ distributions at various primary UHECR energies can be compared with the distributions predicted by detailed detector simulations for any assumed composition and high-energy hadronic interaction model. In this poster, we present measurements of $X_{\rm max}$ by the Telescope Array (TA) fluorescence detectors with stereoscopic shower reconstruction. We find that for all hadronic models considered, the data collected since TA operation began in 2007 is consistent with a chiefly light UHECR composition.
Registration number following "ICRC2015-I/" 772
Collaboration Telescope Array

Primary author

Dr Thomas Stroman (University of Utah)


Dr Yuichiro Tameda (Institute for Cosmic Ray Research, University of Tokyo)

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