Accelerator Cooling - Water leak at Q46W gate valve cooling

Replaced 1/4 hose on gate valve cooling. Q

Vacuum - Ion trapping? Cleo radiation monitors went high and stayed there. Dumped electrons and the radiation dropped. S  Occurs about every third fill or so. S

After losing 260 mA e- beam this morning at about 9:30, leak at 3W gate valve opened up again. It seems to take only about 10 mA of e- to seal the leak, and pressures recover quickly. Positrons do not seal the leak. At about 150 mA of e+ alone the lifetime is about 1 hr. Lifetimes recover immediately when leak seals. The leak got much worse (above 1e-5 torr) on the next (controlled) removal of electrons. Tried the installation of a vacuum dam, but no success, after more than 4 hrs struggle. Used Loc-tite. It worked. W

Control System - Control system computers running with boot node defunct - cesr29 jobs stopped, other tasks in memory running ok, but no new starts possible: cesr29 console running display ok, but otherwise unresponsive - cycle power on cesr29 and b to reboot. F

VGS graphics system hangs about once each shift. S

Console program (+ the magnet clock) hung a couple of times. S

Linac RF - Klystron #8 Focus Coil fuse blew on focus coil #2. M

Found that the Stabiline Voltage regulator for the Linac Modulator Warm-up power is not working properly. Only two of the three phases are regulating. Presumably the variac has a problem. Unit needs to be disassembled (not enough time now) for further inspection and repair. T

Pulsed Magnets - No positron injection, W septum off. Ready chain indicated the first four elements were tripped. After opening the ready chain chassis, we found water dripping from a loose polyflow water cooling line. Ted tightened the connector to stop the dripping. We dried off the cards and and other chassis and replaced the damaged card. Power supply and pulser will not come on. There was a slight burnt resistor smell. Find low level regulation card 5V supply at .8V. Remove 110V from chassis, remove card, Replace 110V. Still .8V. Remove 110V, replace card, replace 110V. T

Feedback - CESR E- Horizontal Feedback Output Timing was off by a train. Q

Horizontal Feedback: Lots of work. Gain increased. Current measurement measured as linear to 10 mA/bunch. Good damping of positrons and electrons, although noise is still a problem. M

CESR RF - The RF wouldn't ramp up after the trip due to the -24V of E1 NIM power supply #1 being out of regulation. The monitor was reading 0.796V. After zeroing, it settled to 0.020V. The voltages on the back of the power supplies looked good, and everything reset ok. Q Replaced NIM Bin Power Supply Monitor for E1 Cavity.  F

Replaced the west RF phase regulator with revised version. F

Warmed West One SRF cavity to 50 K. Cavity/Window pressure went as high as 5e-6 Torr. Cooled down Cryo-Module in about 40 minutes. After, we were able to store 300 mA in two beams in 9x5 bunches. The W1 window vacuum action starts at Pf-Pr at or slightly above 150 kW. All three beam losses were due to the W1 vacuum. W1 will have to be reprocessed to a higher RF power level. T

RF trips off when beam killer is activated, even without beam. Can't find why it now causes quench trips. It is probably due to the new amplitude regulator, but that now works fine in the pulse processing mode W

Increase currents to find trip level: COMET Data here similar but not identical to previous WG arcs? W

beam processing: keeping current at 370 ma to process west RF, lots of vacuum action, up to about 157 kw (fwd-rfl) pwr. W