Rebecca McFadden (University of Melbourne)

UHE Neutrino Detection using the Lunar Cherenkov Technique - Rebecca McFadden Colloquium

ATNF Marsfield Lecture Theatre

Abstract

ABSTRACT

The emerging field of Ultra High Energy (UHE) neutrino astronomy
promises to provide an exceptional probe for distant astronomical
sources. However, direct detection of UHE neutrinos is very difficult
due to their extremely small interaction cross-sections. Instead, they
may be detected indirectly via observation of the AskarÂ’yan effect in
the lunar regolith. Using the Moon as a large volume neutrino
detector, coherent radio Čerenkov emission from neutrino-induced
cascades in the lunar regolith can be observed with ground-based
telescopes (recent experiments have been performed by our
collaboration at both the ATCA and the Parkes Radio Telescope). This
technique poses many interesting technical challenges, including
calibration of the ionospheric dispersion on potential lunar Čerenkov
pulses. I will present a new technique to perform this calibration
using Faraday rotation of polarised emission from the Moon. This
method exploits radial symmetries of the lunar polarisation
distribution to make Faraday rotation measurements in the visibility
domain of synthesis array data. It is particularly attractive for the
lunar Čerenkov technique as it can be used in real time to give values
of the ionospheric TEC which are line-of-sight to the Moon.