Peculiarities of electron-ion collisions in strong magnetic field white dwarfs

We consider electron-ion collisions in strong magnetic field (B > 107 G) white dwarfs at a photospheric temperature T ∼ 104 K. Under these unique conditions, the electron's Larmor radius becomes less than the characteristic impact parameter of the close Coulomb collisions in a non-magnetized plasma. We analyze electron-ion collisions in the classic and in the strong quantum limits which both can be observed in the photospheres of the isolated magnetic white dwarfs. In the both limits, the collision transport frequencies are determined by the close collisions in which an electron transits the region near an ion for a time of the order or less than the cyclotron period. In these effective collisions, an electron returns to an ion many times. The final state of an electron non-regularly (chaotically) depends on its initial state. The strong magnetic field significantly reduces the values of the collision transport frequencies in comparison with the analogous values in a non-magnetized plasma.