Investigation of high amplification events in light curves of gravitationally lensed quasars.

A new parametric representation of the critical curves of the gravitational lens equation is presented. This representation is very useful for the statistical investigation of high amplification events in light curves of gravitationally lensed quasars. We present especially the distribution of the flux factor K (the strength of high amplification events) and the frequency of such events in dependence on the optical depth for microlensing. Some further properties of the normalized lens equation are discussed.