  In this paper we investigate the excitation of longitudinal and transverse
plasma waves in intrinsic Josephson junctions. We consider the outermost branch
of IV characteristic (IVc) in current biased case and try to find the
conditions in which plasma waves can be excited. We change the parameters of
the system and get the corresponding breakpoint current at which the plasma
waves start to initiate. We present specifically the modes containing only
transverse waves where we can have radiation. As a result we find the range of
parameters that the system can radiate.
