Design and Construction

Since EFC is placed in the very high radiation-level area around the beam pipe near the interaction point, it is required to be radiation-hard. Therefore, two options for EFC were considered: 1) a silicon and tungsten sandwich calorimeter and 2) a radiation-hard BGO (Bismuth Germanate, Bi$_4$Ge$_3$O$_{12}$) crystal calorimeter. Both candidates are equally radiation-hard and effective as a beam mask. After studying the two options carefully, we chose the BGO option because it costs less in terms of money and manpower and gives better energy resolution [8].