We search for nuclear recoil signals of dark matter(DM)models with a light mediator using data taken from a p-type point-contact germanium detector of the CDEX-10 experiment at the China Jinping Underground Laboratory...We search for nuclear recoil signals of dark matter(DM)models with a light mediator using data taken from a p-type point-contact germanium detector of the CDEX-10 experiment at the China Jinping Underground Laboratory.The 90%confidence level upper limits on the DM-nucleon interaction cross section from 205.4 kg-day exposure data are derived,excluding the new parameter space in 2−3 GeV DM mass when the mediator mass is comparable to or lower than the typical momentum transfer.We further interpret our results to constrain a specific self-interacting DM model with a light mediator coupling to the photon through kinetic mixing and set experimental limits on the model parameter region favored by astrophysical observations.展开更多
We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of ^(76)Ge....We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of ^(76)Ge.A total of 504.3 kg⋅day effective exposure data was accumulated.The anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was realized.The lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<mββ><3.2–7.5 eV.展开更多
基金Supported by the National Key Research and Development Program of China(2023YFA1607101)the National Natural Science Foundation of China(12425507,12322511,12175112)。
文摘We search for nuclear recoil signals of dark matter(DM)models with a light mediator using data taken from a p-type point-contact germanium detector of the CDEX-10 experiment at the China Jinping Underground Laboratory.The 90%confidence level upper limits on the DM-nucleon interaction cross section from 205.4 kg-day exposure data are derived,excluding the new parameter space in 2−3 GeV DM mass when the mediator mass is comparable to or lower than the typical momentum transfer.We further interpret our results to constrain a specific self-interacting DM model with a light mediator coupling to the photon through kinetic mixing and set experimental limits on the model parameter region favored by astrophysical observations.
基金Supported by the National Key Research and Development Program of China(2017YFA0402201,2022YFA1604701,2022YFA1605000)the National Natural Science Foundation of China(12322511,12175112,12005111,11725522)。
文摘We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of ^(76)Ge.A total of 504.3 kg⋅day effective exposure data was accumulated.The anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was realized.The lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<mββ><3.2–7.5 eV.