Stimulated Brillouin scattering of elliptical laser beam in collisionless plasma

► Self-focusing of elliptical laser beam in collisionless plasma and its effect on SBS is studied. ► Increase in laser intensity leads to decrease in self-focusing of the pump and scattered beam. ► Increase in laser intensity leads to increase in defocusing of the ion acoustic wave. ► There is decrease/increase in SBS reflectivity with increase in laser intensity/plasma density.