The Extreme Universe Space Observatory on board the Japanese Experiment Module of the International Space Station, JEM-EUSO, is being designed to search from space ultra-high energy cosmic rays. These are charged particles with energies from a few 1019 eV to beyond 1020 eV, at the very end of the known cosmic ray energy spectrum. JEM-EUSO will also search for extreme energy neutrinos, photons, and exotic particles, providing a unique opportunity to explore largely unknown phenomena in our Universe. The mission, principally based on a wide field of view (60 degrees) near-UV telescope with a diameter of ∼ 2.5 m, will monitor the earth’s atmosphere at night, pioneering the observation from space of the ultraviolet tracks (290-430 nm) associated with giant extensive air showers produced by ultra-high energy primaries propagating in the earth’s atmosphere. Observing from an orbital altitude of ∼ 400 km, the mission is expected to reach an instantaneous geometrical aperture of Ageo ≥ 2 × 105 km2 sr with an estimated duty cycle of ∼ 20 %. Such a geometrical aperture allows unprecedented exposures, significantly larger than can be obtained with ground-based experiments. In this paper we briefly review the history of space-based search for ultra-high energy cosmic rays. We then introduce the special issue of Experimental Astronomy devoted to the various aspects of such a challenging enterprise. We also summarise the activities of the on-going JEM-EUSO program.
Bibliographical noteFunding Information:
The work on JEM-EUSO and its pathfinders has been supported by the Basic Science Interdisciplinary Research Projects of RIKEN and JSPS KAKENHI Grant (22340063, 23340081, and 24244042), by the Italian Ministry of Foreign Affairs, General Direction for the Cultural Promotion and Cooperation, by the Deutsches Zentrum für Luft- und Raumfahrt, by the Helmholtz Alliance for Astroparticle Physics HAP funded by the Initiative and Networking Fund of the Helmholtz Association (Germany), and by Slovak Academy of Sciences MVTS JEM-EUSO as well as VEGA Grant agency Project 2/0076/13. The Spanish Consortium involved in the JEM-EUSO Space Mission is funded by MICINN under Projects AYA200906037-E/ESP, AYA-ESP 2010 19082, AYA201129489-C0301, AYA201239115-C03 01, CSD200900064 (Consolider MULTIDARK) and by Comunidad de Madrid (CAM) under Project S2009/ ESP-1496. The EUSO Balloon has been supported by the French CNES and IN2P3. The US is supported by the NASA grants NNX13AH55G, NNX13AH53G. Russia is supported by the Russian Foundation for Basic Research Grant No 13-02-12175-ofi-m. Moreover, studies for JEM-EUSO have been partly funded by the European Space Agency (ESA) through the ”EUSO” Topical Team Fund.
© 2015, Springer Science+Business Media Dordrecht.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science