User name R. Michaels
Log entry time 11:25:37 on June13,2004
Entry number 125567
keyword=procedure to dither by hand
Here is how to dither by hand (i.e. position & energy modulation).
Thanks to Kent for these instructions, I slightly edited them.
Eventually this will be more automated.
Procedure to take a beam modulation run
1) Inform Hall B (x5126) a little in advance (15 minutes). Negotiate
with them on when to do modulation.
2) When it is time for the test, end any current HAPPEX parity run.
3) Call MCC and ask that first inform Hall B that the Hall A modulation run is starting.
They should then enable the energy and position modulation in Hall A.
The MCC must turn both energy and position feedback off, and turn "modulation on".
If there is any confusion on their part,
they should follow the
4) Verify that the position lock and RF FastFeedback are off.
The Tools screen should read, left to right,
"OFF FB ON RF OFF"
(We don't know what that FB ON is doing in the middle of things,
but we are told its ok...)
5) On the "greenmonster" GUI (the green GUI with a drawing of Mike
from Monsters, Inc), goi to the the BMW tab, and
click "Start Modulation" from the top box.
If there is
no "Start Modulation" button, click the "Check Status"
button. If there is still no "Start Modulation" button, click "Set Kill Switch" button, then wait
3 seconds, and click "Check Status".
If there is _still_ no "Start Modulation" button, ask the expert
6) Start the parity DAQ, and take 10 minutes (18k events) of "beam
on". Don't count time with the beam off, and subtract add at least one minute for each beam trip.
Verify modulation is happening
by looking at the "Target BPM" and/or "Dithering"
screens of the "happex" panguin configuration.
7) After accumulating >18k events with beam on, end the parity run.
Call MCC and have them turn FastFeedback position and energy lock back
on. Also ask that they inform Hall B that the test is over. (MCC
will also tell them. The redundancy in communication is good.)
8) This step important:
On the greenmonster GUI, press the "Set Kill Switch"
button in the top box.
9) Record this run as a "Dithering run" on the runsheet. Add the
run to the runlist with the phrase "Dithering run" included in the comment field.
Mark the time of this dithering run on the white board so the shift crew knows the next time to take one.
Once per 2 hours, approx. Oh, and you may want to verify from data that dithering is not happening
when you think it is not.