Of possibility to use beam polarization for absolute energy calibration in high-precision measurement of tau lepton mass at vepp-4 m

Results of experiments on measurement of a duration of beam polarization existence in VEPP-4M electron-positron collider ring after injection of a polarized beam from VEPP-3 booster at the energy 1.85 GeV and subsequent deceleration down to the energy of tau-lepton production threshold (1.78 GeV) are presented and analysed.