KAI-FENG CHENPAO-TI CHANGWEI-SHU HOU2021-07-282021-07-28202017480221https://www.scopus.com/inward/record.uri?eid=2-s2.0-85096494444&doi=10.1088%2f1748-0221%2f15%2f10%2fP10002&partnerID=40&md5=88ef4368f8629db06809920c3a78c188https://scholars.lib.ntu.edu.tw/handle/123456789/573598A template fitting technique for reconstructing the amplitude of signals produced by the lead tungstate crystals of the CMS electromagnetic calorimeter is described. This novel approach is designed to suppress the contribution to the signal of the increased number of out-of-time interactions per beam crossing following the reduction of the accelerator bunch spacing from 50 to 25 ns at the start of Run 2 of the LHC. Execution of the algorithm is sufficiently fast for it to be employed in the CMS high-level trigger. It is also used in the offline event reconstruction. Results obtained from simulations and from Run 2 collision data (2015–2018) demonstrate a substantial improvement in the energy resolution of the calorimeter over a range of energies extending from a few GeV to several tens of GeV. ? 2020 CERN for the benefit of the CMS collaboration.Calorimeters; Germanium compounds; Readout systems; Tungsten compounds; Electromagnetic calorimeter; Energy resolutions; Event reconstruction; High-level triggers; Lead tungstate crystal; Proton interactions; Signal amplitude; Template fittings; Signal reconstructionjournal article10.1088/1748-0221/15/10/P100022-s2.0-85096494444