Simulation study on generation of Langmuir waves from Whistler waves by the plasma master

Simulations with a two-dimensional electromagnetic and relativistic particle code show that high-frequency Langmuir waves can be generated by tile plasma maser mechanism from low-frequency whistler waves excited by an electron temperature anistropy. It is confirmed that the plasma maser mechanism does not require an electron beam component for the growth of high-frequency Langmuir waves. We are forced to reconsider the emission mechanism of Langmuir waves observed in space plasmas.