The Energy Spectrum of Ultra-High-Energy Cosmic Rays Measured by the Telescope Array FADC Fluorescence Detectors in Monocular Mode

摘要

We present a measurement of the energy spectrum of ultra-high-energy cosmicrays performed by the Telescope Array experiment using monocular observationsfrom its two new FADC-based fluorescence detectors. After a short descriptionof the experiment, we describe the data analysis and event reconstructionprocedures. Since the aperture of the experiment must be calculated by MonteCarlo simulation, we describe this calculation and the comparisons of simulatedand real data used to verify the validity of the aperture calculation. Finally,we present the energy spectrum calculated from the merged monocular data setsof the two FADC-based detectors, and also the combination of this mergedspectrum with an independent, previously published monocular spectrummeasurement performed by Telescope Array's third fluorescence detector(Abu-Zayyad {\it et al.}, {Astropart. Phys.} 39 (2012), 109). This combinedspectrum corroborates the recently published Telescope Array surface detectorspectrum (Abu-Zayyad {\it et al.}, {Astrophys. Journ.} 768 (2013), L1) withindependent systematic uncertainties.