Background Data Quality Monitoring system(DQM)was developed to monitor data quality at BESⅢexperiment in real time.The stable center-of-mass energy(E_(cms))is essential for the data taking.Online monitoring the E_(cm...Background Data Quality Monitoring system(DQM)was developed to monitor data quality at BESⅢexperiment in real time.The stable center-of-mass energy(E_(cms))is essential for the data taking.Online monitoring the E_(cms)can help find the beam energy shift in time.Purpose The purpose is to monitor the E_(cms)in DQM system in real time.Methods The E_(cms)is measured using Bhabha scattering process in DQM system,due to its large cross section and low background level.The E_(cms)is calculated from the invariant mass of e^(+)e^(-),and the correction value from radiation effect and momentum calibration.Result The E_(cms)calculated with DQM system shows a good consistency with that from offline reconstruction within error.The results are validated with data taken in 2013.The overall systematic uncertainty includes 0.39 MeV/c^(2) from signal extraction and 2.54 MeV/c^(2) from calibration and radiation correction.Conclusions The E_(cms)calculated from Bhabha scattering process is now available on DQM system in real time,which can be used as references for researchers to operate BESⅢexperiment.展开更多
基金provided by National Natural Science Foundation of China(NSFC)under Contracts Nos.11775245,11275210,U1832204
文摘Background Data Quality Monitoring system(DQM)was developed to monitor data quality at BESⅢexperiment in real time.The stable center-of-mass energy(E_(cms))is essential for the data taking.Online monitoring the E_(cms)can help find the beam energy shift in time.Purpose The purpose is to monitor the E_(cms)in DQM system in real time.Methods The E_(cms)is measured using Bhabha scattering process in DQM system,due to its large cross section and low background level.The E_(cms)is calculated from the invariant mass of e^(+)e^(-),and the correction value from radiation effect and momentum calibration.Result The E_(cms)calculated with DQM system shows a good consistency with that from offline reconstruction within error.The results are validated with data taken in 2013.The overall systematic uncertainty includes 0.39 MeV/c^(2) from signal extraction and 2.54 MeV/c^(2) from calibration and radiation correction.Conclusions The E_(cms)calculated from Bhabha scattering process is now available on DQM system in real time,which can be used as references for researchers to operate BESⅢexperiment.
