The ANtarctic Impulsive Transient Antenna (ANITA) is a NASA long-duration balloon experiment based in Antartica. The ANITA detector is composed of an array of radio antennas attached to a giant helium balloon that periodically flies above Antarctica looking for signs of ultra-high energy neutrinos and cosmic rays.
Earth-skimming ultra-high energy neutrinos coming from outside our galaxy interact with the ice in Antarctica and produce Askaryan radiation: this is a radio signal that ANITA can detect from its position at 40km altitude. Ultra-high energy cosmic ray showers interact with the mostly vertical Earth magnetic field in Antarctica and produce a horizontal radio impulse that ANITA can detect.
ANITA has performed four flights so far, with the last ANITA flight in 2016, which gathered over a million events for us to analyse. ANITA has so far published the most stringent constraints on diffuse neutrino fluxes above 1019.5 eV, performed several analyses on cosmic ray showers, and looked for coincidences between our signals and known astrophysical sources.
The Payload for Ultra-high Energy Observation (PUEO) is an upgrade of ANITA is proposed to fly in the mid-2020s.
The QMUL ANITA/PUEO group is heavily involved in the development of the simulation for both ANITA and PUEO.