Use of charge-coupled device imagers for charged-particle spectroscopy

Abstract

We describe preliminary experiments designed to demonstrate the use of charge-coupled device (CCD) imagers as spectroscopic detectors of charged particles. A large-area front-illuminated imager made on p/p+ epitaxial material was irradiated with α particles with energies up to 5.5 MeV and protons up to 13 MeV. The charge per event agrees reasonably well with calculations that assume a collection zone comprising the p epilayer and the portion of the p+ substrate within a diffusion length of the p epilayer. The charge per event for these particles is relatively large, often exceeding the CCD well capacity in the case of α particles, and therefore some of the stressing requirements of other applications, such as low dark current and low read noise, are not essential in this case. The results indicate that CCD imagers are excellent candidates for applications such as charged-particle diagnostics of inertial confinement fusion implosions.