Design of the Online Integral Dose Monitor System for BESIII EMC

Abstract

High beam current of BEPCII leads to high radiation background around the interaction point where the ElectroMagnetic Calorimeter (EMC), a key sub-detector of BESIII, is located. The performance of EMC degrades due to accumulated exposure to the high radiation background. In order to monitor the integral dose deposited in the EMC, an online integral dose monitor system has been developed according to the study on 400nm IMPL RadFET. This system consists of 72 RadFETs located around EMC. A microcontroller based DAQ box can readout all the RadFET information and send to computers via an Ethernet interface. The detail of this system and the BEPC testing result are presented in this paper.