In this paper,propagation characteristics of electromagnetic electron cyclotron(EMEC)waves based on kappa-Maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Ea...In this paper,propagation characteristics of electromagnetic electron cyclotron(EMEC)waves based on kappa-Maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Earth’s magnetic field and auroral trapped electrons.The dispersion relation for EMEC waves in kappa-Maxwellian distributed plasma has been derived using the contribution of the parallel electric field and trapped electron speed.Numerical results show that the presence of the electric field has a stimulating effect on growth rate,which is more pronounced at low values of wave number.It is also observed that as the threshold value of trapped electron speed is surpassed,it dominates the effect of the parallel electric field and EMEC instability is enhanced significantly.The electric field acts as another source of free energy,and growth can be obtained even in the absence of trapped electron drift speed and for very small values of temperature anisotropy.Thus the present study reveals the interplay of the parallel electric field and trapped electron speed on the excitation of EMEC waves in the auroral region.展开更多
Inverse Bremsstrahlung absorption(IBA) of an intense laser field in plasma containing Maxwellian and nonMaxwellian(with Kappa and q-nonextensive distribution functions) electrons is studied analytically. Our results s...Inverse Bremsstrahlung absorption(IBA) of an intense laser field in plasma containing Maxwellian and nonMaxwellian(with Kappa and q-nonextensive distribution functions) electrons is studied analytically. Our results show that IBA decreases with an increase in temperature at high intensities and a decrease in plasma density for all kinds of distribution functions. Another striking result is that IBA is independent of the laser intensity at low intensity but is dependent on it when the intensity is going to rise. Also, it could be find that the behavior of the absorption as the function of laser intensity for the Kappa distribution with κ= 10 at low intensity is close to that for the Maxwellian distribution, but at high intensity it is close to that in the presence of q-nonextensive electrons with q = 0.9. These results provide insights into the inverse Bremsstrahlung absorption in the laser-plasma interactions.展开更多
基金This research was supported by the GC University grant No.241/ORIC/19 dated 27-08-2019National Natural Science Foundation of China Grant No.41874190.
文摘In this paper,propagation characteristics of electromagnetic electron cyclotron(EMEC)waves based on kappa-Maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Earth’s magnetic field and auroral trapped electrons.The dispersion relation for EMEC waves in kappa-Maxwellian distributed plasma has been derived using the contribution of the parallel electric field and trapped electron speed.Numerical results show that the presence of the electric field has a stimulating effect on growth rate,which is more pronounced at low values of wave number.It is also observed that as the threshold value of trapped electron speed is surpassed,it dominates the effect of the parallel electric field and EMEC instability is enhanced significantly.The electric field acts as another source of free energy,and growth can be obtained even in the absence of trapped electron drift speed and for very small values of temperature anisotropy.Thus the present study reveals the interplay of the parallel electric field and trapped electron speed on the excitation of EMEC waves in the auroral region.
文摘Inverse Bremsstrahlung absorption(IBA) of an intense laser field in plasma containing Maxwellian and nonMaxwellian(with Kappa and q-nonextensive distribution functions) electrons is studied analytically. Our results show that IBA decreases with an increase in temperature at high intensities and a decrease in plasma density for all kinds of distribution functions. Another striking result is that IBA is independent of the laser intensity at low intensity but is dependent on it when the intensity is going to rise. Also, it could be find that the behavior of the absorption as the function of laser intensity for the Kappa distribution with κ= 10 at low intensity is close to that for the Maxwellian distribution, but at high intensity it is close to that in the presence of q-nonextensive electrons with q = 0.9. These results provide insights into the inverse Bremsstrahlung absorption in the laser-plasma interactions.
