Current status of luminosity measurement with the CMD-3 detector

摘要

The CMD-3 detector has begun to take data at the electron-positron collider VEPP-2000 since december 2010. The collected data sample corresponds to an integrated luminosity of 60 pb~(-1) in the c.m. energy range from 0.32 up to 2GeV and about 50pb~(-1) for RUN2017. The integrated luminosity was measured by counting e~+e~- → e~+e~- and e~+e~- → γγ events, allowing additional photons in the final state. Preliminary results of the luminosity measurement are presented for various energy ranges and its accuracy is estimated to be 1%.