arXiv subjects

Aula Al-Adulrazzaq

Publications and source records attributed to Aula Al-Adulrazzaq.

2 recordsLinked to original sources

arXiv2026

Anisotropic electron scattering and Migdal effect in semiconductor detectors

Cryogenic semiconductor detectors are widely used in dark matter direct detection. Electronic excitations in these materials can be caused either by direct dark matter electron scattering events, or indirectly via dark matter nuclear scattering events. For nuclear scattering of light dark matter, the event rate is enhanced due to an inelastic process known as the Migdal effect. Both the electron recoils and the Migdal effect in semiconductors depend on the dielectric function of the target material via the so-called energy loss function (ELF). In the standard approach found in the literature, the ELF is approximated as isotropic to simplify the calculation of the event rate. We introduce a practical method for computing the event rate for a general anisotropic ELF. We find that the daily modulation of the Migdal rate arises solely due to the quadrupole component of the ELF, whereas in electron scattering all spherical harmonic components affect the rate. We apply the formalism to study the daily modulation in silicon and gallium arsenide detectors.

hep-ph↗

arXiv2025

Fast numerical evaluation of dark matter direct detection event rates

The mathematical expression for the dark matter nuclear recoil event rate in a detector consists of a six dimensional integral over the velocity distribution of dark matter in the detector frame, and over the recoil momentum of the nucleus. While a significant part of this integral can be solved in closed form under traditional assumptions of the standard halo model and/or isotropic detector response, analysis of alternate assumptions is conventionally impeded by the inefficiency of multidimensional numerical integration methods. In this work we introduce a novel, fast and efficient algorithm for direct detection event rate computations. This algorithm takes advantage of a closed form expression for the Radon transform of three dimensional Zernike functions, which are used as basis functions for the velocity distribution. We demonstrate an implementation of this algorithm ZebraDM (https://github.com/sebsassi/zebradm), which is typically faster than an optimized numerical integration approach by a factor between $10^2$ and $10^4$.

hep-ph↗