Total stopping carbon calorimeters are used to measure electron beam fluence. The carbon element is sized to totally stop the electron beam. Type E thermocouples are used to measure the total energy deposited in the calorimeter element.

The calorimeter elements are designed to be mounted in ATJ graphite equilibrator plates to minimize heat losses to the surroundings during the time required for the calorimeter element to equilibrate. Arrays of total stopping calorimeters are used to map fluence as a function of radius and axial distance from an anode plane and to measure the total energy delivered at the tangent plane.

The equilibration plates which define the calorimeter array are, in general, custom-made for a specific simulator and/or experiment. Special orders for calorimeter elements, equilibration plates, and /or complete systems are welcome.