Search for Axion-Like-Particles by Atomic Inelastic Transition of Inverse Primakoff Scattering

Chih-Pan Wu^1*, 劉承邦^2,3, Lakhwinder Singh^4,5, Greeshma Chandrabhanu^4,5, 陳俊瑋^6,3, 紀信昌², ‪Mukesh Kumar Pandey⁶, 王子敬⁴

¹Département de Physique, Université de Montréal, Montréal, Québec, Canada
²物理學系, 國立東華大學, 花蓮, Taiwan
³物理組, 國家理論科學研究中心, 台北, Taiwan
⁴物理研究所, 中央研究院, 台北, Taiwan
⁵Department of Physics, Central University of South Bihar, Gaya, India
⁶物理學系, 國立台灣大學, 台北, Taiwan

* Presenter:Chih-Pan Wu, email:chih-pan.wu@umontreal.ca

Axions are hypothetical particles first introduced to solve the strong CP problem with the spontaneous breaking of the Peccei-Quinn symmetry. As well-motivated dark matter candidates, they have evolved from the original “QCD axions” to variants generically called “axionlike particles” (ALPs), whose masses and coupling strengths with matter are no longer related. In general, they can be produced in the Sun or as viable candidates to the cosmological dark matter, and decay to two photons or interact with matter via Inverse Primakoff (IP) interactions. In direct detection experiments, we identify inelastic channels to the IP-processes due to atomic excitation and ionization in additional to the elastic scattering. Their cross-sections are derived with full electromagnetic fields of atomic charge and current densities, and computed by well-benchmarked atomic many-body methods. Therefore, new parameter space of ALP masses between 0.1 eV to 1 MeV can be probed by considering either solar or DM-ALP cases.

Keywords: dark matter, axion-like-particle, atomic interaction