Interaction of a relativistic dense electron beam with a laser wiggler in a vacuum: self-field effects on the electron orbits and free-electron laser gain Abbasi, E.; Jafari, S.; Hedayati, R. Journal of Synchrotron Radiation 23(Part 6): 1282-1295 2016 1600-5775 10.1107/s1600577516012601 https://eurekamag.com/research/058/134/058134891.php