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9:46: Emi : take a noise data [RF OFF, F/D off, COR off], ch1:FAB(w/ HPF), ch2:WSM, ch3:RF, ch4:Scintillator
Average scope is 16sweeps.
MR vacuum : 5.9E-7 Pa.
11:21: Wire on WSM appears broken on inspection.
Inspection before run start indicated that it was intact.
Broke due to vibration or beam heating? -- no signal observed in early tests today.
Wire was fallen down from the frame. This was caused by the vibration of the rod when its position changed by motor drive.
11:22 begin h=2 testing.
Starting with highest frequency h=2 test. If issues are apparent we will move down to next energy.
38MeV h=2 tripped amplifier at half amplitude
35MeV h=2 tripped amplifier
28MeV h=2 tripped amplifier.
12:03 Begin stacking test using the AWG script below, we will try a few differnt runs with differnt lengths of coasting. The Script is ~50ms long and the machine rep rate is 20hz so we have minimised the time between pulses as much as possible. The flattop after the recapture is 2ms long, roughly 20 synchrotron oscillations (6000 turns). Hopefully that is enough to gauge the intensity and run tomography. We cannot run a longer flattop at 4kV because that would trip the RF amplifier.
12:12 bit of trouble getting the machine and the RF shaker to work at 20Hz rep rate
RF is running at 10Hz rep rate and shaker is running at 20Hz.
Looks like the issue is that the AWG script is too long. We will make one with less coast.
Actually Ishi-san and Uesugi-san fixed it -- working now with original AWG script.
Setting the shaker timing - set to 38.970ms
Taking one data series with shaker in middle of stationary bucket region to confirm beam kill
Shaker voltage set to 8V
Taking data with the shaker on/off. Shaker is timed so that it fires at the end of the flattop.
It may be possible to run the machine at 20hz and the shaker at 10 hz, ie kick out every other stacked beam. We will try this after lunch. This method allows us to quantify the intensity due to exactly 1 extra beam.
13:00 Linac is down
14:32
Schottky spectra for the beam stacking test for the window shown below
Schottky spectra for shaker on and shaker off. When the shaker is off we "should" be stacking the beam from the previous cycle
zoom into h=3
Amplitude indicates possibly marginal intensity increase for stacked beam -- however, does not rule out amplitude fluctuations due to ion source, linac, etc. Hence data with averaging will be taken.
Took averaged data with the shaker on and off to get a basis for the change in Intensity
14:49 We will try to set the shaker such that it shakes every other beam, ie running the shaker at 10hz with the machine at 20hz.
set shaker timing 88.970ms so it now fires for every other acceleration cycle
Set the scope trigger to sync with the shaker pulse
Took data with 10hz shaker and with the shaker in the middle of the rebunch as that might kick the beam out more efficiently
Averaging signal is performing strangely. Taken unaveraged data as signal is looking reasonably stable. Results should be taken as preliminary.
Taking FAB and tora data for the nomial kurns RF, ie for comparison to the script I made using Shinji's python script
16:12. Phase displacement measurements
set scraper postion, different to last time since the scraper is now the frame of emi's WSM
Phase displacement AWG scripts have wrong injection energy (my [Carl William Jolly's] fault, I knew about this last week and forgot to make new ones)
17:19
Quickly take perturbation by empty bucket measurements
took data for adb and 4kv debunch
We saw a signal when the empty bucket appears for both the 4kv and adb case. It could be the empty bucket capturing beam that was lost earlier in the acceleration cycle or it could be from the empty bucket perturbing the coasting beam!!
move onto h-2 test with latest scripts
22MeV h=2 script tripped the amplifier
16MeV h=2 script operational. Data taken.
16MeV h=1 script operational. Data taken. RF amplitude 'almost the same as before'
17:44 Begin test of h=2 19MeV. Tripped amplifier at last possible instant. Slightly smaller amplitude may work.
17:46 loading RF scripts for double peak 10 segment test.
note!! we really need to rename .equ files after they are made or at least before importing them -- trying to find the right tmp_x_y_z_a_b_c_d_e_f.equ is a nightmare...
Below: Schottky spectrum of dataset with 20Hz rep rate, 10Hz shaker repetition.
Quick look at DoublePeak10seg data by SM, at 18:00 UK on 29 January
#33: -2 MeV, #34: -1 MeV, #35: 0 MeV, #36: +1 MeV deleceleration or acceleration after recapturing. I expected Schottky signal moves ~20 kHz/1 MeV. The results below shows no move. From top, #33 to #36.
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