Exothermic Dark Matter with Light Mediator after LUX and PandaX-II in 2016

• Published in: arXiv.org
• Main Authors: Chao-Qiang Geng, Huang, Da, Chun-Hao, Lee
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 18.09.2017
• Subjects: Couplings; Dark matter; Physics - High Energy Physics - Experiment; Physics - High Energy Physics - Phenomenology
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1705.06546

Dark matter (DM) direct detections are investigated for models with the following properties: isospin-violating couplings, exothermic scatterings, and/or a light mediator, with the aim to reduce the tension between the CDMS-Si positive signals and other negative searches. In particular, we focus on the non-standard effective operators which could lead to the spin-independent DM-nucleus scatterings with non-trivial dependences on the transfer momentum or DM velocity. As a result, such effective operator choices have the very mild effects on the final fittings. Furthermore, by including the latest constraints from LUX, PandaX-II, XENON1T and PICO-60, we find that, for almost all the considered models, the predicted CDMS-Si signal regions are either severely constrained or completely excluded by the LUX, PandaX-II, XENON1T and PICO-60 data, including the most promising Xe-phobic exothermic DM models with/without a light mediator. Therefore, we conclude that it is very difficult for the present DM framework to explain the CDMS-Si excess.