Robust<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>CsBr</mml:mi><mml:mo>/</mml:mo><mml:mi>Cu</mml:mi></mml:math>photocathodes for the linac coherent light source
Physical review special topics. Accelerators and beams