JEM-EUSO experiment for extreme energy cosmic ray observation

TL;DR

The JEM-EUSO experiment aims to observe ultra-high-energy cosmic rays from space, measuring their energy spectra and sources with a large UV telescope onboard the ISS, significantly surpassing ground-based detectors in aperture.

Contribution

This paper presents the design and objectives of the JEM-EUSO space-based observatory for cosmic ray detection, highlighting its novel large aperture and space-based observation capabilities.

Findings

Design of a 2.5 m UV telescope for cosmic ray detection

Projected energy spectrum measurement up to 1000 EeV

Enhanced aperture compared to ground-based detectors

Abstract

The planned JEM-EUSO (Extreme Universe Space Observatory onboard the ISS Japanese Experimental Module) will measure the energy spectra of cosmic rays up to the range of 1000 EeV and will search for direction to their sources. It will observe the extensive air showers generated in the atmosphere by high energy cosmic ray primary particle from the space. The instantaneous aperture of the telescope will exceed by one order the aperture of the largest ground based detectors. JEM-EUSO apparatus is a large telescope with a diameter of 2.5 m with fast UV camera. Slovakia is responsible for the determination of the UV background, which influences the operational efficiency of the experiment and for the analysis of fake trigger events.