READOUT ARCHITECTURE OF A HIGHLY SEGMENTED SILICON CALORIMETER OPERATING IN-SPACE

We present the design of a readout system for a silicon calorimeter wi th 12800 readout channels, to be operated on satellite or balloon-born e experiments for cosmic antiproton and antihelium search. A prototype of the calorimeter digital readout system has been designed and const ructed. It may be subdivided into two main parts: the storage modules and the controller. Performance tests of the prototype at the acquisit ion rate of 8 MHz result in a very limited power consumption, amountin g to 0.1 mW per channel for the Storage Modules and 0.5 W for the cont roller. The acquisition rate can be further enhanced by simple modific ations of the transmission protocol between the storage modules and th e controller. This readout system can be easily adapted to other detec tors to be operated on space vehicles. An enhanced version of this pro totype is presently used in a gamma spectroscopy balloon-borne experim ent.