IceAct: Imaging Air Cherenkov Telescopes with SiPMs at the South Pole for IceCube-Gen2

Abstract

IceCube-Gen2 is planned to extend the IceCube Neutrino Observatory at the geographic South Pole. For neutrino astronomy, a large sample of well-reconstructed astrophysical neutrinos with very low background is essential. The main background for this signal consists of muons and neutrinos, which are produced in cosmic-ray air showers in the Earth's atmosphere. The coincident detection of these air showers by the surface detector IceTop has already proven the concept of vetoing atmospheric neutrinos and muons in a limited field of view centered around the South Pole. This motivates a large extension of IceTop to detect cosmic rays more efficiently over a large field of view. As part of these extension plans, small imaging air Cherenkov telescopes based on SiPM cameras and optimized for harsh environments, referred to as IceAct are considered. Compared to IceTop stations, these telescopes may be an efficient way to lower the detection threshold for air showers at the cost of a lower duty cycle. In addition small ACTs in combination with IceTop and IceCube can improve the capabilities to measure the composition of the CR spectrum starting at 2 PeV. We will present the progress and future plans of the IceAct project including first coincident data of an IceAct prototype with IceCube.