Budgeting the emittance of photoemitted electron beams in a space-charge affected emission regime for free-electron laser applications oleh Y. Chen, M. Krasilnikov, M. Gross, P. Huang, I. Isaev, C. Koschitzki, X.-K. Li, O. Lishilin, G. Loisch, R. Niemczyk, A. Oppelt, H.-J. Qian, G. Shu, F. Stephan, G. Vashchenko