We report constraints on the dark photon effective kinetic mixing parameter (κ) with data taken from two p-type point-contact germanium detectors of the CDEX-10 experiment at the China Jinping Underground Laboratory. The 90% confidence level upper limits on κ of solar dark photon from 205.4 kg-day exposure are derived, probing new parameter space with masses (m V) from 10 to 300 eV=c 2 in direct detection experiments. Considering dark photon as the cosmological dark matter, limits at 90% confidence level with m V from 0.1 to 4.0 keV=c 2 are set from 449.6 kg-day data, with a minimum of κ ¼ 1.3 × 10 −15 at m V ¼ 200 eV=c 2 .

We present improved constraints on couplings of solar axions and more generic bosonic dark matter particles using 737.1 kg-days of data from the CDEX-1B experiment. The CDEX-1B experiment, located at the China Jinping Underground Laboratory, primarily aims at the direct detection of WIMPs using a p-type point-contact germanium detector. We develop the profile likelihood ratio method for analysis of data in the presence of backgrounds. The background modeling is compatible with the data and no excess signals are observed. An energy threshold of 160 eV was achieved. This significantly improve the sensitivity for the bosonic dark matter below 0.8 keV. Limits are also placed on the coupling gAe < 2.26 × 10 −11 from Compton, bremsstrahlung, atomic-recombination and deexcitation channels and g ef f AN × gAe < 4.14 × 10 −17 from a 57 Fe M1 transition at 90% confidence level. All the constrains improve over our previous results.

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We report new constraints on light dark matter (DM) boosted by blazars using the 205.4 kg day data from the CDEX-10 experiment located at the China Jinping Underground Laboratory. Two representative blazars, TXS 0506+56 and BL Lacertae are studied. The results derived from TXS 0506+56 exclude DM-nucleon elastic scattering cross sections from 4.6 × 10 −33 cm 2 to 1 × 10 −26 cm 2 for DM masses between 10 keV and 1 GeV, and the results derived from BL Lacertae exclude DMnucleon elastic scattering cross sections from 2.4 × 10 −34 cm 2 to 1 × 10 −26 cm 2 for the same range of DM masses. The constraints correspond to the best sensitivities among solid-state detector experiments in the sub-MeV mass range.