High Current Run I2015 Feb 3 22:45 to Feb. 4 23:00 High Current Run II2015 Feb 5 12:15 to Feb. 6 13:00

Current ~ 20 mA

Approx. 40 trips, i.e. fast shutter closes

~ 75 % appear to be Gun HVPS tripping off

~ 25 % other

ERL Injector Trip Studies

These are the fast signals we monitored during the two 24 hours runs:

• Gun HVPS voltage reading

• Cavity phases (we were biased toward looking at the phases rather than amplitudes because the “RF Field OK” signal seemed to only fail on amplitude).

• The output of the discriminator connected to the coupler PMTs

• A beam amplitude signal from a bpm before the dump (four BPM signals to an RF combiner , output of combine to a mixer to produce a 12.5 MHz signal which went to the scope)

These signals were added part way through the two 24 hour runs:

• An analog signal from a coupler PMT (I don’t think the analog coupler PMT signal told us more than the discriminator output)

• A fast (log) amplitude and phase signal from a BPM in A1

Typical “Gun” Trip

don’t know what started this, beam amplitude is steady, cavity 2 trips off later

0.1 V = 5 degrees

beam signal at dump is affected by RF ?, dump quad detector closes shutter, no RF trips off(similar to Feb. 4 10:39 Trip)

0.1 V = 5 degrees

cause ?, beam steady, after shutter closes arc and pressure trips on cavity 4

0.1 V = 5 degrees

subsequently arc and pressure trips, all cavities trip

0.1 V = 5 degrees

cavity response driven by beam disturbance ?, a later trip shows same behavior with no beam disturbance A2 closes shutter, all RF trips off

0.1 V = 5 degrees

cavity response driven by beam disturbance, dump quad detector closes shutter, no RF trips off,

A1 Beam Phase, Amplitude

0.1 V = 5 degrees

Glitch in A1 beam intensity, cavity 1 closes shutter ?, cavity 1 trips off later (similar to Feb. 4 11:30:48 Trip)

0.1 V = 5 degrees