Collision photon echo in magnetic field

In this article it was described collision induced photon echo, which is formed by two laser pulses with orthogonal polarizations on the transition with the angular momentum change 0 - 1. The dependence of the echos intensity versus the ellipticity of laser pulses was found. It was shown that echos intensity has maximum provided that laser pulses are linear and up to zero for circular orthogonal polarization. It was found reduction effect of photon echos signal in longitudinal magnetic field. This effect may be used for measuring the relaxation rates due to such collisions.