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Extreme Universe Space Observatory

February 6, 3:30pm - 4:30pm
Mānoa Campus, Watanabe Hall, 112

The Department of Physics and Astronomy Colloquium: Prof. Thomas Weiler (Vanderbilt University) to speak on " Extreme Universe Space Observatory (EUSO)."

The Extreme Universe Space Observatory (EUSO) is a consortium of 250 researchers drawn from 14 countries, working to put a 2.5 meter, down-looking Fresnel lens on the International Space Station (ISS). The purpose is to gather a hundred extreme energy (above 10^20 eV) cosmic-ray events (and 1000 events above 50 EeV) to finally reveal the cosmic origin and dynamics of such events. The instantaneous aperture of JEM-EUSO is 50 times that of Auger; the time-averaged aperture is 9 times that of Auger. The ISS circles the Earth every 90 minutes, thereby providing EUSO with all-sky coverage at a nearly constant efficiency. A launch date of 2018 is a possibility. Open issues to be studied with the EUSO event sample include

(i) showering details (Xmax, muon abundance, variance in fluctuations, ~E) -- do we understand QCD at such energies?
(ii) composition - e.g., are the primaries dominantly protons or nuclei? Are there photons, as might be expected from super-massive DM decay? Any detectable neutrinos?
(iii) source type - Galactic versus extragalactic origins, inference of massive black holes;
(iv) GZK suppression of the spectrum versus energy-bounds on cosmic accelerator capabilities;
(v) the crossover point in the spectrum, from a Galactic flux to an extragalactic flux.
Speculative goals include observations of, or bounds on, extreme-energy photons, neutrinos, magnetic monopoles, dark matter particles, etc.

Ticket Information

Event Sponsor
Physics and Astronomy, Mānoa Campus

More Information
Dr. Frederick Harris, 808-956-2940,

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