scholarly journals Erratum: “Stimulated Brillouin backscattering and ion acoustic wave secondary instability” [Phys. Plasmas 16, 032701 (2009)]

2009 ◽  
Vol 16 (8) ◽  
pp. 089902 ◽  
Author(s):  
B. I. Cohen ◽  
E. A. Williams ◽  
R. L. Berger ◽  
D. Pesme ◽  
C. Riconda
2009 ◽  
Vol 16 (3) ◽  
pp. 032701 ◽  
Author(s):  
B. I. Cohen ◽  
E. A. Williams ◽  
R. L. Berger ◽  
D. Pesme ◽  
C. Riconda

2009 ◽  
Vol 27 (12) ◽  
pp. 4409-4427 ◽  
Author(s):  
P. A. Bernhardt ◽  
C. A. Selcher ◽  
R. H. Lehmberg ◽  
S. Rodriguez ◽  
J. Thomason ◽  
...  

Abstract. An ordinary mode electromagnetic wave can decay into an ion acoustic wave and a scattered electromagnetic wave by a process called stimulated Brillouin scatter (SBS). The first detection of this process during ionospheric modification with high power radio waves was reported by Norin et al. (2009) using the HAARP transmitter in Alaska. Subsequent experiments have provided additional verification of this process and quantitative interpretation of the scattered wave frequency offsets to yield measurements of the electron temperatures in the heated ionosphere. Using the SBS technique, electron temperatures between 3000 and 4000 K were measured over the HAARP facility. The matching conditions for decay of the high frequency pump wave show that in addition to the production of an ion-acoustic wave, an electrostatic ion cyclotron wave may also be produced by the generalized SBS processes. Based on the matching condition theory, the first profiles of the scattered wave amplitude are produced using the stimulated Brillouin scatter (SBS) matching conditions. These profiles are consistent with maximum ionospheric interactions at the upper-hybrid resonance height and at a region just below the plasma resonance altitude where the pump wave electric fields reach their maximum values.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
B. Eliasson ◽  
A. Senior ◽  
M. Rietveld ◽  
A. D. R. Phelps ◽  
R. A. Cairns ◽  
...  

AbstractStimulated Brillouin scattering experiments in the ionospheric plasma using a single electromagnetic pump wave have previously been observed to generate an electromagnetic sideband wave, emitted by the plasma, together with an ion- acoustic wave. Here we report results of a controlled, pump and probe beat-wave driven Brillouin scattering experiment, in which an ion-acoustic wave generated by the beating of electromagnetic pump and probe waves, results in electromagnetic sideband waves that are recorded on the ground. The experiment used the EISCAT facility in northern Norway, which has several high power electromagnetic wave transmitters and receivers in the radio frequency range. An electromagnetic pump consisting of large amplitude radio waves with ordinary (O) or extraordinary (X) mode polarization was injected into the overhead ionosphere, along with a less powerful probe wave, and radio sideband emissions observed on the ground clearly show stimulated Brillouin emissions at frequencies agreeing with, and changing with, the pump and probe frequencies. The experiment was simulated using a numerical full-scale model which clearly supports the interpretation of the experimental results. Such controlled beat-wave experiments demonstrate a way of remotely investigating the ionospheric plasma parameters.


2017 ◽  
Vol 35 (2) ◽  
pp. 226-233 ◽  
Author(s):  
P. Sharma

AbstractIn the present work, excitation of nonlinear ion acoustic wave (IAW) in collisionless plasma by laser beam having null intensity at the center is examined considering relativistic nonlinearity. The differential equation for beam-width parameter is determined considering relativistic nonlinearity using the paraxial and Wentzel–Kramers–Brillouin approximations by the parabolic equation method. The propagation features of the IAW are found to be modified due to the nonlinearity present in the system. The hollow Gaussian beam (HGB) gets nonlinearly coupled with the seed IAW, results in excitation of nonlinear IAW. The interaction of nonlinear IAW with pump beam demonstrated stimulated Brillouin scattering (SBS) of HGB. It is found that the power of IAW and power of SBS is affected with the order of HGB. The power of IAW and backscattered power of SBS is determined analytically and numerically for various orders of HGB. It is found that the power of IAW and the backscattering is diminished for higher order of HGB.


2016 ◽  
Vol 35 (1) ◽  
pp. 81-91 ◽  
Author(s):  
R. Gauniyal ◽  
N. Ahmad ◽  
P. Rawat ◽  
B. Gaur ◽  
S.T. Mahmoud ◽  
...  

AbstractStimulated Brillouin backscattering of an intense hollow Gaussian laser beam (HGLB) from collisionless plasma has been investigated under relativistic–ponderomotive regime. The main feature of considered hollow Gaussian laser beam is having the same power at different beam orders with null intensity at the center. Backscattered radiation is generated due to nonlinear interaction between main beam (pump beam) with pre-excited ion acoustic wave (IAW). Modified coupled equations has been set up for the beam width parameters of the main beam, ion-acoustic wave, back-scattered wave, and back reflectivity of stimulated Brillouin scattering (SBS) with the help of the Wentzel–Kramers–Brillouin approximation, fluid equations and paraxial theory approach. These coupled equations are solved analytically and numerically to study the laser intensity in the plasma, the variation of amplitude of the excited IAW and back reflectivity of SBS. The back reflectivity of SBS is found to be highly sensitive to the order of the HGLB, intensity of main laser beam, and plasma density for typical laser and plasma parameters. The focusing of main laser beam (hollow Gaussian) and IAW significantly affected the back reflectivity of SBS. The results show that the self-focusing and back reflectivity is enhanced for higher order modes of HGLB.


2013 ◽  
Vol 31 (4) ◽  
pp. 689-696 ◽  
Author(s):  
R.P. Sharma ◽  
Ram Kishor Singh

AbstractThis paper presents an investigation for excitation of ion acoustic wave and resulting stimulated Brillouin scattering in a collisionless plasma due to presence of a laser beam carrying null intensity at center (hollow Gaussian beam). In presence of ponderomotive nonlinearity, the pump beam get focused and affects the back stimulated Brillouin scattering process. To understand the nature of laser plasma coupling, a paraxial-ray approximation has been invoked for the propagation of the hollow Gaussian beam, ion acoustic wave, and stimulated Brillouin scattering. It is observed from the result that self-focusing and back reflectivity reduces for higher order of hollow Gaussian beam.


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