Studying Ultra-High-Energy Cosmic Rays from International Space Station with whe JEM-EUSO telescope: status and perspectives
by
M. Casolino(RIKEN, INFN-)
→
Europe/Stockholm
Description
The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) of the International Space Station (ISS) will study from space Ultra High-Energy Cosmic Rays (UHECR), measuring its spectrum from 3*10^19 eV and above the Greisen-Zatsepin-Kuzmin (GZ) suppression energy, looking for possible astrophysical sources.
JEM-EUSO will observe the Ultraviolet (290-430 nm) light emitted in Extensive Air Showers (EAS) produced by UHECRs traversing the Earth's atmosphere. For each event, the detector will determine the primary energy, the arrival direction and nature of the primary particle.
The advantage of a space-borne detector resides in the larger field of view, using a target volume far greater than what is achievable from ground, and a uniform sampling of the whole celestial sphere, looking for possible anisotropies in the extragalactic space.
The corresponding increase in statistics will help to clarify the origin and sources of UHECRs and characterize the intergalactic environment crossed during their production and propagation.
JEM-EUSO instrument meets the requirements of spatial and temporal photon detection over a large field of view with the limitation posed with space-borne detectors. It is a 1.1 ton refractor telescope using a system of 2.2 m diameter Fresnel lenses with 60 degrees field of view, focusing the UV-light from EAS on a focal surface composed of about 300,000 channels, composed by 6,000 multianode photomultipliers. A multi-layer parallel architecture handles front-end acquisition selecting and storing valid triggers. An infrared camera and a LIDAR system on-board and a global light
system on the ground will also be used to monitor the earth’s atmosphere and to calibrate the telescope instruments.
The instrument is being preceded by a ground based pathfinder, located in front of one of Telescope Array fluorescence detectors in Utah. Also a series of balloon flights, sponsored by CNES, French Space agency, are currently being prepared. The first of these is planned to take place in 2013 from Timmins, Canada.
We will discuss the mission, its perspectives and the status of the precursors and the main instrument.
