The background study at 555 m deep underground with superheated emulsion detector

Abstract

The study of the background events is an important part in any Dark Matter direct search experiment. An exploratory run at a depth of 555 m is performed at Jaduguda Underground Science Laboratory (JUSL), Jaduguda, Jharkhand by using C2H2F4 (b.p. −26.3 °C) superheated emulsion detector, fabricated at the surface laboratory at SINP. The active liquid C2H2F4 is a potential target for the low mass DM search. The main objective was to study the background events including the noise level at the underground lab and compare it with the surface lab. It has been observed that the count rate of background events at JUSL is reduced by a factor of 2 than that at the surface lab. The expected event rate for the neutrons at JUSL has been estimated. The projected sensitivity of C2H2F4 for 10 kg days of exposure has also been discussed for the zero background events.