A Full Digital MAPS Based EM Calorimeter and its Applications

by Dr Hongkai Wang (Nuclear and Radiation Safety Center, MEE)

Friday 21 Jun 2019, 10:00 → 11:30 Asia/Shanghai

B326 (IHEP)

Abstract: The novel concept of a compact fully digital silicon-tungsten sampling electromagnetic calorimeter with an ultra-high granularity has been proposed as an upgrade of ALICE experiment at CERN for the measurements of direct photons in forward regions. To facilitate the R&D process of the design, a proof-of-principle compact prototype has been successfully developed by a team from the Utrecht University, the Netherlands based on Monolithic Active Pixel Sensors (MAPS) with a pixel size of 30×30 µm2 and a total depth of 28 X0. In total 39M pixels with ultra-fine granularity allows obtaining the unprecedented detailed knowledge of the electromagnetic showers in both transverse and longitudinal directions. Furthermore, the small Molière radius provides the crucial capability for two-photon separation. The prototype was extensively tested using particle beams and cosmic muons. The speaker has played a leading role in operating this platform in both experiments and simulations in the Utrecht team. Moreover, he refines the alignment procedures to the level of a few micrometer. Based on this, he managed to devise and implement a method to determine the position of electromagnetic shower with a precision of 30 µm. This talk will majorly present the R&D activities as well as test-beam results of this prototype, and will also cover perspectives of some other applications with this technology. Brief CV of the speaker: • Postdoctoral researcher, 2018-present, Nuclear and Radiation Safety Center, MEE, • Ph.D. Particle Physics, 2018, Utrecht University, the Netherlands. • M.A. Nuclear Physics, 2013, China Institute of Atomic Energy. • B.S. Microelectronics, 2010, Sichuan University.

Slides EPD_Seminar_MAPS_ECAL_HongkaiWang_2019_0621.pdf