2025/10/09 by Y. F. Liang, L. T. Yang, Liang, Y. F. +169
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Instrumentation and Detectors (physics.ins-det) #Scientific Research and Discoveries
paper · pdf · doi:10.48550/arxiv.2510.07800
openalex publication_date 2025/10/09 · openalex created_date 2025/10/18 · openalex updated_date 2026/07/30
We present limits on spin-independent inelastic weakly interacting massive particles (WIMP)-nucleus scattering using the 737.1 kg⋅day dataset from the CDEX-1B experiment. Expected nuclear recoil spectra for various inelastic WIMP masses mχ and mass splittings δ are calculated under the standard halo model. An accurate background model of CDEX-1B is constructed by simulating all major background sources. The model parameters are then determined through maximum likelihood estimation and Markov chain Monte Carlo fitting. The resulting 90% confidence level upper limits on the WIMP-nucleon cross section σn exclude certain DAMA/LIBRA allowed regions: the χ2 < 4 regions for δ< 30 keV at mχ= 250 GeV and the χ2 < 9 region for δ< 50 keV at mχ= 500 GeV. The method is applicable to other inelastic dark matter scenarios, and the upcoming CDEX-50 experiment is expected to improve sensitivity by four orders of magnitude.