Thermal Model Improvement in Phonon Detection Channels Using a Scintillating Crystal

We present the development of a heat flow model utilizing a scintillating crystal for heat and light detection. By analyzing the measured light signals from \(\alpha\) $\alpha$ - and \(\beta\) $\beta$ / \(\gamma\) $\gamma$ -induced events in a CaMoO \(_4\) ${}_4$ crystal, we describe the time-dependent behavior of the scintillation emission and the subsequent generation of delayed phonons in the crystal. The phonon detection channel model incorporates both prompt and delayed generation of athermal phonons; these are absorbed in a phonon collector film on the crystal surface or converted into a thermal phonon distribution in the crystal. A reasonable agreement is observed in the comparison between the measured signals and the simulated signals derived from the model study. We attribute the observed pulse shape discrimination to the presence of the delayed phonons associated with the scintillation process.