Noise Performance Evaluation of the Candidate Digitizers for the MAJORANA DEMONSTRATOR

摘要

The noise performance evaluation of the two digitizer cards being considered for the MAJORANA DEMONSTRATOR (MJD) is presented in this document. The procurement of the data acquisition electronics for the MJD is scheduled to happen this year. At the time of writing this document, there are two candidate digitizer electronic boards. One aspect that is being considered by the collaboration is the feasibility of using the MJD for dark matter searches. The feasibility of using the MJD for this application is going to be dictated by the ability of the demonstrator to reach sub-keV energy resolution. One of the potential sources of noise in the MJD is the data acquisition system. This document will is concluded with a recommendation for the final digitizer board by comparing the noise performance of the two electronics systems. Noise parameters such as the effective number of bits, input range linearity and signal to noise ratio are experimentally determined. The two digitizer cards feature different on-board digital signal processing and these features are compared. The experimental set-up was also used to identify sources of noise. This paper describes these sources of noise in the data acquisition system, along with mitigation strategies. Issues such as grounding and wiring scheme have an impact in the overall data acquisition system performance and are discussed in detail. As a conclusion, the suitability of each one of the cards to become the back bone of the data acquisition system of the MJD is discussed.