Jun 26 – 27, 2023
America/Chicago timezone

Precision ionization calibrations of silicon skipper CCDs for dark matter detection

Jun 27, 2023, 10:15 AM
One West (Fermilab)

One West



Rachana Suthikshn Yajur (University of Chicago)


Direct dark matter detection experiments can reach the thresholds as low as $\mathcal{O}$(10eV). In that regime, we report precision ionization measurements induced by Compton scattering of gamma rays and nuclear recoils from neutrons. A skipper charge-coupled device (CCD) with single electron resolution developed for DAMIC-M experiment was used to collect data. Compton scattering on silicon atomic shell electrons down to 23 eV was measured using a $^{241}$Am source and compared with Monte Carlo simulations and ab initio calculations. Nuclear recoil ionization efficiency of silicon nuclei was measured using a SbBe source and Monte Carlo simulations were used to model the nuclear recoil spectrum. Agreements with simulations for Compton scattering and the deviation of nuclear recoil ionization efficiency from the extrapolated Lindhard model will be dicussed.

Primary author

Rachana Suthikshn Yajur (University of Chicago)

Presentation materials