Dr. Kimberly Palladino

Abstract:

The Antarctic Impulsive Transient Antenna (ANITA) experiment is being developed to search for ultra-high-energy (UHE) neutrino interactions ($>3\times10^{18}$ eV) in the Antarctic ice cap. A neutrino interaction in the ice will produce a radio pulse by the means of the Askaryan effect. The large radio transparency of ice allows for such a pulse to be recorded by a cluster of balloon-borne antennas. The details of the ANITA instrument, now in a construction phase, and the science we hope to achieve is discussed. In order to prepare for the main mission, we have flown ANITA-lite during the 2003/04 austral season. ANITA-lite consisted of two quad-ridge horn antennas and a prototype RF (radio frequency) triggering and recording system. Here we present the results of an impulsive RF background survey of Antarctica, as well as proof-of-principle gain, tracking, and timing calibrations conducted by observing solar radio emissions and calibration radio-pulses. A preliminary UHE neutrino flux limit based on ANITA-lite data is also presented.

Abstract:

The ANITA experiment is a balloon-borne radio-pulse detector system designed to measure Ultra-High Energy (UHE) neutrinos interacting in the Antarctic ice utilizing the distinct broadband radio pulse due to the Askaryan effect. The radio-transparent ice serves as a target volume for the production of these pulses. ANITA will have an effective viewing area of over one million km2 of ice at float altitude (∼37 km). A prototype experiment, ANITA-LITE, was flown during the 2003-2004 Austral Summer from Antarctica to perform an impulsive RF background survey of Antarctica. In the process, it has yielded strong constraints on UHE neutrinos, ruling out some theoretical models. We also discuss the expected instrument performance for the first full ANITA flight, planned for a 2006 Austral Summer launch out of McMurdo, Antarctica.

Abstract:

ANITA is a balloon borne radio telescope designed to detect the interactions of ultra-high energy (UHE) neutrinos (> 3x1018 eV) in the Antarctic ice cap. These interactions produce Cherenkov radiation in the form of a distinct broadband radio pulse known as the Askaryan effect. The pure, radio transparent Antarctic ice cap serves as an almost ideal medium for the generation of these pulses and ANITA will have an effective viewing area of one million km2 at float altitude. A prototype experiment, ANITA-LITE was flown during the 2003/2004 Austral summer from Antarctica to do an impulsive RF background survey. We present a discussion of the instrumentation and technique we will use to utilize the ice cap as a detector to measure the UHE neutrino flux.