History and Current Status of In-Ice Radio Frequency (RF) Neutrino Detection

As of this writing, there are three dedicated experiments based in Antarctica which seek first-ever measurement of the ultra-high-energy ("UHE", E-nu >100 PeV) neutrino flux at Earth by exploiting the Askaryan effect. All three (ANITA, ARA and ARIANNA) target detection of the so-called 'cosmogenic neutrinos' which should result from interactions of ultrahigh-energy baryons with the Cosmic Microwave Background Radiation (CMBR). Photoproduction of charged pions, via N gamma -> Delta -> N pi(+/-), with subsequent weak decays of those charged pions, results in neutrinos of typical energies two decades lower in energy than the primary progenitor. Subsequent in-ice weak and neutral scattering of those neutrinos off ice molecules can yield a detectable pulse of coherent, RF radiation. We will discuss the status of the latter of those three experiments (ARA and ARIANNA), which seek to measure ultra-high-energy neutrinos using antennas which are buried into Antarctic snow. Professor Dave Seckel of the University of Delaware will review the status of the balloon-borne ANITA experiment.