Askaryan Radio Array: searching for the highest energy neutrinos

Abstract: Searches for ultra-high energy ($E_\nu \geq 10$ PeV) cosmogenic and astrophysical neutrinos (UHENs) have been conducted by several experiments over the last two decades. The Askaryan Radio Array (ARA), located near the geographical South Pole, was one of the first two experiments that used radio antennas sensitive to orthogonal polarizations for detection of neutrino-induced Askaryan radiation. ARA comprises five independent autonomous stations, with an additional low threshold phased array merged with station 5, which were deployed at a depth of 100-200 m over the period 2012-2018, corresponding to a total livetime of more than 27 station years. In this article, we present a brief overview of the detector, its detection technique, and discuss a few of its major achievements with a focus on the current status of the array-wide UHEN search. We expect to produce the most sensitive results on the neutrino flux by any existing in-ice neutrino experiment below 1000 EeV energy.