Open AccessA method of measuring the incidence angle of intense electron beam
Author(s) -
Yang Hu,
Hu Yang,
Jianfeng Sun,
Jie Sun,
Peng-Fei Zhang
Publication year - 2015
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.64.245203
Subject(s) - optics , pitch angle , electron , beam (structure) , angle of incidence (optics) , cathode ray , materials science , faraday cup , faraday cage , physics , computational physics , atomic physics , ion beam , magnetic field , quantum mechanics , geophysics
In recent years, a great many of effect data obtained from the high current pulsed electron beam play an important role in the studying of X-ray thermal-mechanical effects. Energy deposition profile is the criterion to measure the equivalence of thermal-mechanical effects between high-current electron beam and X-rays. To adjust the energy deposition profiles to improve the equivalence of the simulations of X-ray and thermal-mechanical effect, the intense electron beam energy deposition profile measurement should be studied. Two-dimensional distribution measurement which is an important part of the energy deposition profile is to obtain a two-dimension (r, θ) incidence angle distribution. A new method of measuring the incidence angle based on small Faraday cup array covered with aluminum films, called modified multi-layer stacking, is presented in this paper. With the help of the filtered Faraday cups, the transmission fraction of the electron beam confined at a specific position and time is stored. Two-dimension incidence angle distribution on the anode target that changes over the working time is obtained with these transmission fractions by computer calculation. The result indicates that the two-dimension incidence angle distribution has a close relationship with the pinch of the beam. The electrons tend to move vertically to the equipotential line when the diode is under Child-Langmuir flow, then they hit the target in a small angle range (E×B drift, the trajectory of the electrons becomes a slanted helix with pitch changing. The incidence angle then increases to about 60° from small angle.