Neutron beam test of CsI crystal for dark matter search

Abstract We have studied the response of Tl- and Na-doped CsI crystals to nuclear recoils and γ's below 10 keV . The response of CsI crystals to nuclear recoil was studied with mono-energetic neutrons produced by the 3 H ( p , n ) 3 He reaction. This was compared to the response to Compton electrons scattered by 662 keV γ-ray. Pulse shape discrimination between the response to these γ's and nuclear recoils was studied, and quality factors were estimated. The quenching factors for nuclear recoils were derived for both CsI(Na) and CsI(Tl) crystals.