The resolution and the linearity of time measurements made with the CMS electromagnetic calorimeter are studied with samples of data from test beam electrons, cosmic rays, and beam-produced muons. The resulting time resolution measured by lead tungstate crystals is better than 100 ps for energy deposits larger than 10 GeV. Crystal-to-crystal synchronization with a precision of 500 ps is performed using muons produced with the first LHC beams in 2008. © 2010 IOP Publishing Ltd and SISSA.
Chatrchyan, S., Khachatryan, V., Sirunyan, A. M., Adam, W., Arnold, B., Bergauer, H., … White, A. (2010). Time reconstruction and performance of the CMS electromagnetic calorimeter. Journal of Instrumentation, 5(3). https://doi.org/10.1088/1748-0221/5/03/T03011