Maser-beam instability of Bernstein waves

The present study constitutes a continuation and improvement of the precedi ng work by Yoon [J. Geophys. Res. 104, 19801 (1999)]. In the present discus sion, an instability of Bernstein waves excited by a beam of energetic elec trons is investigated. Special attention is paid to the regime where the ra tio of plasma frequency, omega (pe), to electron gyrofrequency, Omega (e), is sufficiently higher than unity. An approximate but fairly accurate schem e is introduced to deal with the situation dictated by the condition, omega (2)(pe)/Omega (2)(e)much greater than1. The present investigation is motiv ated by the research in solar radiophysics. However, in this article the em phasis is placed on basic properties of the instability rather than its app lication. (C) 2000 American Institute of Physics. [S1070-664X(00)02811-1].