TY - RPRT TI - Harmonic generation in a terawatt x-ray free-electron laser AU - Freund, H. P. (ORCID:0000000222238760) AU - O’Shea, P. G. PY - 2024 DO - 10.1088/1402-4896/ad40d8 UR - https://www.osti.gov/biblio/2345798 ID - 2345798 ER -