The project of laser polarimeter for beam energy measurement of VEPP-4M collider by resonance depolarization method
To high precision measurement of Υ-meson masses on VEPP-4M - KEDR accelerator complex the beam energy calibration is needed. The project of laser polarimeter for beam energy measurement by resonance depolarization method is discussed. The polarization measurement is based on up-down asymmetry of Compton backscatterring of circular polarized photons on vertical polarized electrons. Scattered photons are registered by two-coordinate GEM detector. Expected effect is about 1% with ten sigma confidence level.