Speaker
Description
The Selena Neutrino Experiment couples an amorphous selenium (aSe) ionization target to a complimentary metal-oxide-semiconductor (CMOS) pixel array as an imaging detector for next-generation neutrino physics. The high $Q_{\beta\beta}$ of $^{82}$Se and the excellent image-based event classification allows for a neutrinoless $\beta\beta$ decay search free from environmental backgrounds. We present the R&D status of Selena, including the design and characterization of TopmetalSe, the first prototype pixel array designed specifically for charge collection in aSe. Prototype devices consist of an array of 100$\times$100 pixels with 15 $\mu$m pitch coupled to 500 $\mu$m-thick aSe. We present the spectroscopic and track-imaging performance of the first-generation of devices, which already meet several specifications for Selena.
