Oak Ridge National Laboratory

Physics Division

Physics Division Seminars

Physics Division Seminars bring us speakers on a variety of physics related subjects. Usually these are held in the Building 6008 large Conference Room, at 3:00 pm on the chosen day, but times and locations may vary. For more information, contact our seminar chairman,

Alfredo Galindo-Uribarri
Tel (Office): (865) 574-6124  (FAX): (865) 574-1268

Thu., May 31, 2012, at 3:00 p.m. (refreshments at 2:40 p.m.)

The moon as a detector of Ultra-High-Energy neutrinos

Olaf Scholten, KVI, Univ. of Groningen
Building 6008, Large Conference Room

Cosmogenic particles at ultra-high energies (UHE, E>1020 eV, about 1 Joule) are the messengers of the most energetic processes in the universe. Their energy is orders of magnitude higher than reachable at CERN. The quest is to find their origin. Neutrinos are especially suited for this as they y unobstructed in straight lines. The expected flux of UHE neutrinos is about 1 particle per square kilometer per year, steeply falling with energy, making it necessary to work with large detectors. When an UHE particle hits the lunar surface a very strong electromagnetic pulse is generated through a process known as the Askaryan effect. This mechanism will be explained and it is argued that in an observing window around 150 MHz there is a maximum chance for detecting this radiation on Earth with radio telescopes commonly used in astronomy. Using this principle we have set a new limit on the flux of neutrinos with energies in excess of 4_1022 eV in 50 hours of observation time with the Westerbork Synthesis Radio Telescope array. In the near future, the digital radio array LOFAR will be used to perform a more sensitive observation. The status of this project, the NuMoon project, will be presented. Reference: Europhysics News, 42(2011)26; DOI= http://dx.doi.org/10.1051/epn/2011506

Alfredo Galindo-Uribarri