AES9 exceeds ILC spec with NO field emission during second pass qualification

AES9 reached 36 MV/m at Q0 9E10 without any field emission during the second pass qualification test on 7th October, 2009.

AES9 initially reached 34 MV/m at Q0 1E10 during the first RF test following first light EP. A strong field emitter turned on during the final power rise - limiting the performance to 30 MV/m. The cavity was later on re-EP processed for a total EP removal of 20 (10+10) microns followed by HPR, assembly and 120Cx48hr bake. As can be seen from the graph, AES9 exceeded ILC vertical test spec during the second-pass test.

AES9 was also pre-tuned before re-EP for field flatness of 98% and achieved frequency at 2K of 1299.739 MHz (target being 1299.700 MHz). AES9 can now be included in tyhe CM2 at Fermi Lab