Search

We report results of a search for light weakly interacting massive particle (WIMP) dark matter from the CDEX-1 experiment at the China Jinping Underground Laboratory (CJPL). Constraints on WIMP-nucleon spin-independent (SI) and spin-dependent (SD) couplings are derived with a physics threshold of 160 eVee, from an exposure of 737.1 kg-days. The SI and SD limits extend the lower reach of light WIMPs to 2 GeV and improve over our earlier bounds at WIMP mass less than 6 GeV., Comment: 10 pages, 10 figures

Germanium detectors with sub-keV sensitivities [1, 2, 3] offer a unique opportunity to study neutrino interactions and properties [4] as well as to search for light WIMP Dark Matter [5, 6]. The TEXONO and CDEX Collaborations have been pursuing this research program at the Kuo-Sheng Neutrino Laboratory in Taiwan and in the China Jinping Underground Laboratory in China. We will present highlights of the detector R&D program which allow us to experimental probe this new energy window. The results, status and plans of our neutrino physics program will be discussed, with focus on the quest on neutrino-nucleus coherent scattering.

We present in the poster the status of an R&D program towards the goal of an ultra-low-energy germanium (ULEGe) detector at threshold of 100 eV with an active target mass on the order of 1 kg and a background near threshold at the range of 1 event/kg-keV-day [1]. The scientific objectives include the studies of neutrino-nucleus coherent scattering and neutrino magnetic moments, as well as WIMP dark matter searches at the low WIMP mass range. Such detectors would also have potential implications in reactor monitoring for security purposes. A threshold of 220 eV has been demonstrated with a prototype 4-channel ULEGe array with a total mass of 20 g [2]. Competitive limits have been derived for WIMP-nucleon couplings for WIMPs with mass less than 10 GeV. Scale-up plans are described.