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arXiv · 1601.06363

Detection prospects of the Telescope Array hotspot by space observatories

D. Semikoz·P. Tinyakov·M. Zotov
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Abstract

In the present-day cosmic ray data, the strongest indication of anisotropy of the ultrahigh energy cosmic rays is the 20-degree hotspot observed by the Telescope Array with the statistical significance of 3.4\sigma. In this work, we study the possibility of detecting such a spot by space-based all-sky observatories. We show that if the detected luminosity of the hotspot is attributed to a physical effect and not a statistical fluctuation, the KLYPVE and JEM-EUSO experiments would need to collect ~300 events with E>57 EeV in order to detect the hotspot at the 5\sigma\ confidence level with the 68% probability. We also study the dependence of the detection prospects on the hotspot luminosity.

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D. Semikoz, P. Tinyakov, M. Zotov. 2016-01-24. Detection prospects of the Telescope Array hotspot by space observatories. https://doi.org/10.1103/physrevd.93.103005

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