Dark Matter Still at Large

Abstract

We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35 × 10 4 kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c −2 , WIMP-nucleon spin-independent cross sections above 2.2 × 10 −46 cm 2 are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1 × 10 −46 cm 2 at 50 GeV c −2 .

Ruling Out ∼100–300 GeV Thermal Relic Annihilating Dark Matter by Radio Observation of the Andromeda Galaxy

“…Recent direct-detection experiments give negative results on dark matter search. Either the interaction cross section between dark matter and normal matter is very small or dark matter mass is larger than our expected value (Aprile et al 2017;Cooley 2017). The benchmark model of WIMP dark matter in which the observationally inferred dark matter abundance is obtained through the thermal freeze-out mechanism predicts m ≈ 220 GeV with σv ≈ 10 −26 cm 3 s −1 (Bertone et al 2018).…”

The radial acceleration relation in galaxy clusters

“…Also the small scales (1 − 10 kpcs) are not devoid from issues (e.g., Moore 1994;Moore et al 1999;Ostriker & Steinhardt 2003;Boylan-Kolchin et al 2011Oh et al 2011;Del Popolo & Hiotelis 2014;Del Popolo & Le Delliou 2014Zhou et al 2017;Chang et al 2018;Chang & Zhou 2019), as the cusp/core problem (Moore 1994;Flores & Primack 1994), the "miss-⋆ chanmh@eduhk.hk † adelpopolo@oact.inaf.it ing satellite problem" (Moore et al 1999), the "Too-Big-To-Fail problem" (Garrison-Kimmel et al 2013). Another issue of the ΛCDM model is the lack of detection of the dark matter component of the model (Tan et al 2016;Akerib et al 2017;Cooley 2017). Therefore, this long list of problems has ruled out a huge portion of the available parameter space of cold dark matter, especially for the most popular candidate -weakly interacting massive particles (WIMPs).…”

Constraining annihilating dark matter mass by the radio continuum spectral data of NGC4214 galaxy

“…Future radio detection by the Square Kilometre Array (SKA) may be able to constrain thermal relic DM mass up to 10 TeV [49]. In fact, the null result of DM direct-detection experiments [50,51] may suggest that DM mass is of the order or larger than ∼ 1 TeV [52]. Some recent analyses of the DAMPE data indicate that DM mass may be even larger than 1.4 TeV [53,54].…”