Abstract:
The Banded emission of Oxygen cyclotron harmonic waves has been observed by Van
Allen probes in the Earth inner magnetosphere. The general dispersion relation for
electrostatic Oxygen cyclotron harmonic waves is derived by using Lerche-Newberger sum
rule for Maxwellian and Kappa distributions. Oxygen ion kappa spectral index (𝜅𝑖𝑂) has a
significant impact on the Oxygen cyclotron harmonic waves. The quasi Maxwellian
behavior is being observed as 𝜅𝑖𝑂 β₯ 5. The curves shift toward the higher value of
wavenumber, as the value of 𝜅𝑖𝑂 reduce. There is an increase in super-thermal particles as
we reduce the value of 𝜅𝑖𝑂. By decreasing the value of 𝜅𝑖𝑂, the super-thermal particles
reduce the frequency , 𝜔𝑝𝑒𝑎𝑘 , where the group velocity vanish and the associated 𝑘𝑝𝑒𝑎𝑘 get
increase. These cyclotron harmonic waves may be useful for the diagnostic for the velocity
distribution characteristics. Oxygen cyclotron harmonic waves can be helpful for the
diagnostic of Van Allen Radiation Belts.
