Molière radius measurement using a compact prototype of LumiCal in a test set-up

Abstract

The FCAL collaboration has performed a design study for luminometers at future electronpositron colliders. Compact sampling calorimeters with precisely positioned silicon sensors and a fast readout will reach the necessary performance even in the presence of background from beamstrahlung and two-photon processes. A prototype calorimeter has been built with special focus on ultra-thin fully instrumented sensor planes to ensure a very small effective Molière radius. Preliminary results of measurements in a 5 GeV electron beam are presented.

4 pages, 4 figures, talk presented at the 39th International Conference on High Energy Physics (ICHEP2018), Seoul, Korea, 4-11 July, 2018