Dual degrees of freedom diagnosis with high energy electron lens radiography

The evolution of electromagnetic field and fluid is important in the research of high energy density physics, controlled nuclear fusion, and laboratory astrophysics. But in experiment, it is difficult to get the density and electromagnetic field distribution simultaneously. Based on high energy electron lens radiography, this paper proposes dual degrees of freedom diagnosis (DDFD) by constructing areal density difference. Combining the Monte-Carlo simulation and beam optics analysis, the feasibility of this method when the diagnosed system includes relatively strong electromagnetic field has been validated. Besides, changing the aperture as a ring can effectively improve the resolution in low E/B field and low areal density situation. The simulation results indicate that this method works well. Considering the characters of electron beams, this method is quite suitable for the electromagnetic fluid diagnosis.