Collective excitations and low-energy ionization signatures of relativistic particles in silicon detectors
Year: 2024
Type: article
Abstract: Solid-state detectors with a low energy threshold have several applications, including searches of non-relativistic halo dark-matter particles with sub-GeV masses. When searching for relativistic, beyond-the-Standard-Model particles with enhanced cross sections for small energy transfers, a small detector with a low energy threshold may have better sensitivity than a larger detector with a higher energy threshold. In this paper, we calculate the low-energy ionization spectrum from high-velocity particles scattering in a dielectric material. We consider the full material response including the excitation of bulk plasmons. We generalize the energy-loss function to relativistic kinematics, and benchmark existing tools used for halo dark-matter scattering against electron energy-loss spectroscopy data. Compared to calculations commonly used in the literature, such as the Photo-Absorption-Ionization model or the free-electron model, including collective effects shifts the recoil ionization spectrum towards higher energies, typically peaking around 4-6 electron-hole pairs. We apply our results to the three benchmark examples: millicharged particles produced in a beam, neutrinos with a magnetic dipole moment produced in a reactor, and upscattered dark-matter particles. Our results show that the proper inclusion of collective effects typically enhances a detector's sensitivity to these particles, since detector backgrounds, such as dark counts, peak at lower energies.
Source: Communications Physics
Authors: Rouven Essig, Ryan Plestid, Aman Singal
Institutions: Stony Brook University, California Institute of Technology
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,790
Awards: G1099677550, G154696372, G2695919875, G3013229095, G3710524638, G4682315529, MRI: Acquisition of SeaWulf - A Reconfigurable Computer System for Research and Education, NUCLEON DECAY AND NEUTRINO EXPERIMENTS, RESEARCH ACCOMPLISHMENTS AND GOALS OF THE THEORETICAL HIGH ENERGY PHYSICS GROUP, G6239086211, G716412294, G8046890258, RESEARCH ACCOMPLISHMENTS AND GOALS OF THE THEORETICAL HIGH ENERGY PHYSICS GROUP, G86560745
OpenAlex ID: W4405611629