ANOMALOUS DAMPING IN PLASMA

The imaginary part of the dispersion laws of charged collective excitations in plasma (electron excitations in the usual plasma, and quark and gluon excitations in quark-gluon plasma) is discussed. It turns out to be anomalously large - much larger than the inverse free path time that determines the relaxation processes in plasma. We show, however, that anomalous damping effects are rather difficult to detect experimentally. In particular, by performing the resummation of an infinite set of the relevant ladder graphs, we show that the low-frequency polarization operator of the electromagnetic currents does not involve an anomalous damping dependence. Nevertheless, the anomalous damping effects can in principle be seen. In particular, they affect the infrared cut-off in the logarithmic integrals for the characteristic relaxation time. In the low-density Boltzmann plasma they affect this significantly and change the argument of the Coulomb logarithm.