Contribution
Limit on the UHE neutrino flux from Centaurus A with the Parkes radio telescope
Presenter: Justin Bray (University of Adelaide)
Abstract: Active galactic nuclei such as Centaurus A have been proposed as sources of ultra-high energy (UHE) cosmic rays and neutrinos. When these neutrinos interact in the lunar regolith, they will generate electromagnetic cascades of relativistic particles, which produce Cherenkov radiation at radio frequencies. Radio telescopes may therefore be used to observe UHE neutrinos indirectly, by searching for the nanosecond-scale pulses that these cascades produce. The most recent such experiment was with the Parkes radio telescope in March 2009, and employed a new scheme to discriminate against impulsive radio-frequency interference. It was optimised for sensitivity to any UHE neutrino flux from Centaurus A. The non-detection from this experiment allows us to place an upper limit on this flux.