Low Energy Neutrino and Mass Dark Matter Detection Using Freely Falling Atoms

• DOI: 10.48550/arxiv.2302.09874
• Publication Date: 2023-01-01
• Authors: Ruzi, Alim; Qian, Sitian; Yang, Tianyi; Li, Qiang
• Keywords: 0301 basic medicine; High Energy Astrophysical Phenomena (astro-ph.HE); Condensed Matter - Mesoscale and Nanoscale Physics; Atomic Physics (physics.atom-ph); FOS: Physical sciences; 7. Clean energy; High Energy Physics - Experiment; Physics - Atomic Physics; High Energy Physics - Phenomenology; 03 medical and health sciences; High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Astrophysics - High Energy Astrophysical Phenomena

We propose a new method to detect low-energy neutrinos and low-mass dark matter at or below the MeV scale, through their coherent scatterings from freely falling heavy atoms and the resulting kinematic shifts. We start with a simple calculation for illustration: for $10^7$ heavy atoms of a mass number around 100 with a small recoil energy of 1 meV, the corresponding velocities can reach $0.01, {\rm m/s}$ and produce significant kinematic shifts that can be detected. We then show that the proposed device should be able to probe vast low-energy regions of neutrinos from meV to MeV and can surpass previous limits on sub-MeV dark matter by several orders of magnitude. Such a proposal can be useful to (1) detect sub-MeV-scale dark matter: with $10^2$ atom guns shooting downwards, for example, CsI or lead clusters consisting of $10^{7}$ atoms with a frequency around $10^3$ Hz, it can already be sensitive to scattering cross-sections at the level of $10^{-33 (-34)}\rm{cm}^{2}$ for 1 (0.1) MeV dark matter and surpass current limits. Technological challenges include high-quality atom cluster production and injections. (2) Measure coherent neutrino-nuclei scatterings at the 0.1-1 MeV region for the first time: with $10^4$ atom guns shooting downwards CsI clusters consisting of $10^{11}$ atoms and a frequency of $10^{6}$ Hz. One can expect 10 events from MeV solar neutrinos to be observed per year. Furthermore, (3) this method can be extended to probe very low-energy neutrinos down to the eV-KeV region and may be able to detect the cosmic neutrino background, although it remains challenging.<br/>5 pages, 2 figures; a new method to probe low energy/mass world, refs added<br/>