Macroscopic symptoms of collapse in REB-plasma interaction experiments in strong magnetic field

At present, it is well recognized that strong Langmuir turbulence is excited during the process of intense REB-plasma interaction. According to theoretical predictions the energy of Langmuir oscillations can be transferred to plasma electrons by a collapse mechanism. Experimental evidence of the collapse phenomenon has been already observed in a rare nonmagnetized plasma with an electron beam of low energy. As to the case of strong turbulence of broad spectrum of Langmuir oscillations in the presence of a magnetic field, up to now there is no theoretical grounds of the Langmuir waves collapse as a nonlinear stage of modulational instability. Besides, at present, there is no any experiment on the collapse phenomenon observation in a strong magnetic field. In this paper the first macroscopic manifestations of the collapse are presented. The minimum size of the collapsing cavitons is estimated as ℓmin<30rD.