Conveners
1008D
- Yongchao Zhang (Southeast University)
The $S_8/\sigma_8$ tension in the large scale structure can be explained by decaying dark matter with an almost degenerate spectrum and small enough decay width. Here we propose the Gemini dark matter model, which contains a heavy mother particle $\chi_3$ and two twins $\chi_{1/2}$ which are almost degenerate in mass and are produced at the same time. The dark sector is charged under the same...
We study multi-component dark matter scenarios and the Galactic 511 keV gamma-ray emission line signal in the framework of a local, dark U(1)_D extension of the Standard Model. A light vector dark matter particle associated with the dark U(1)D may decay and annihilate to electron-positron pairs. The produced positrons may in turn form positroniums that subsequently annihilate to two photons,...
Axion-like particles (ALPs) and dark photons (DPs) are viable dark matter particle candidates that multiple underground experiments have investigated. We have searched for possible ALP/DP signals in the PandaX-4T liquid xenon detector using 94.8 days of data. A binned likelihood fit is constructed to scan for possible mono-energetic peaks induced by the absorption processes between ALPs/DPs...
This study reanalyzes the detection prospects of dark matter (DM) annihilation signals in the Galactic Center, focusing on velocity-dependent dynamics within a spike density near the supermassive black hole (Sgr A⋆). We investigate three annihilation processes --pp-wave, resonance, and forbidden annihilation -- under semi-relativistic velocities, leveraging gamma-ray data from Fermi and DAMPE...
