Radial velocity measurements in prominences using a Fabry-Perot interferometer

A Fabry-Perot (FP) interferometer combined with the 35-cm coronagraph of the Pulkovo Observatory are utilized to measure the radial velocities of solar prominences. The movement of the FP interferometer piezoelectric elements which produces a spectral scan are studied, and the radial velocity is measured by examining the optical elements and calibration pulses. The procedures for recording the data and the advantages provided by the simultaneous recording of the reduction and working signals are described. An example of a prominence recording is presented.