Control of electron beam in bubble regime produced by high intense laser plasma interaction

Ultrashort laser sources have been developed by the C.PA technique in the recent years .This progress causes to produce quasi-monoenergetic electron during the laser-plasma interaction. Such high quality electron beams are generated by different mechanisms. One of the new and effective methods is to prepare the cavity or bubble regime when an ultrashort laser pulse propagates in underdense plasma. In this work we discuss about how to control the output electron energy beam in the cavity regime with using a proper parabolic plasma density profile and discuss about quality of the mentioned beam. The result shows the mentioned profile can control gain and energy of the quasi-monoenergetic electron beam.