Energy Spectrum of Ultra-High Energy Cosmic Rays Observed with the Telescope Array Using a Hybrid Technique

TL;DR

This paper presents the measurement of ultra-high energy cosmic ray spectrum using a hybrid detection technique with the Telescope Array, combining fluorescence and surface detector data for improved accuracy over 2.3 years.

Contribution

It introduces a hybrid reconstruction method that enhances the accuracy of cosmic ray arrival directions and energies, validated with data from the Telescope Array.

Findings

Spectrum agrees with previous Telescope Array results

Consistent with HiRes measurements

Demonstrates effectiveness of hybrid detection technique

Abstract

We measure the spectrum of cosmic rays with energies greater than $10^{18.2}$ eV with the Fluorescence Detectors (FDs) and the Surface Detectors (SDs) of the Telescope Array Experiment using the data taken in our first 2.3-year observation from May 27 2008 to September 7 2010. A hybrid air shower reconstruction technique is employed to improve accuracies in determination of arrival directions and primary energies of cosmic rays using both FD and SD data. The energy spectrum presented here is in agreement with our previously published spectra and the HiRes results.