Power pulsing of the CALICE tile hadron calorimeter

Abstract

A large scale prototype of a tile hadron calorimeter (HCAL) for the International Linear Collider (ILC) detector is currently under development. The proposed calorimeter follows the particle flow concept, which requires high granularity and a compact detector design. This is accomplished by using scintillating tiles that are read out by Silicon Photomultipliers (SiPMs) and the integration of the associated front-end electronics into the gaps between the absorber plates. In order to keep the calorimeter structure homogeneous and simple, no active cooling system is allowed for the inner detector. In consequence, the power dissipation of the front-end electronics has to be limited as far as possible with an aim of 25μW per channel. The key component to achieve this is switching off the consumers of the front-end electronics during the gaps in between the ILC bunch trains (power pulsing). In this contribution we show the first results for power pulsing with a full-extension prototype of 2.20m length. Following to a description of the setup, we compare results for the detector performance with and without power pulsing. The challenges of switching huge supply currents of several amperes in 5Hz rate to the front-end electronics and the experiment's power supplies are addressed as well as electromagnetic compatibility aspects.