Difference between revisions of "Spot++"
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https://logbooks.jlab.org/system/temporary/FADC_prex_21079.pdf | https://logbooks.jlab.org/system/temporary/FADC_prex_21079.pdf | ||
| + | == How To Take a spot++ run == | ||
| − | + | # Log into the a-onl account | |
| − | # | ||
#* <font face="Courier">ssh –X aonl@aonl2 –l a-onl</font> | #* <font face="Courier">ssh –X aonl@aonl2 –l a-onl</font> | ||
# If part of a [[Beam Recovery]] procedure, make sure you have taken a CODA run in [[CODA#Starting Counting Mode DAQ CODA | counting mode]] for the LHRS | # If part of a [[Beam Recovery]] procedure, make sure you have taken a CODA run in [[CODA#Starting Counting Mode DAQ CODA | counting mode]] for the LHRS | ||
| − | # [[Switching Modes#Note about high voltages|Scintillator HVs (S0A,B and S3 in each arm)]] need to be on to | + | # Monitoring the beam positions |
| − | #Then type either: | + | #* |
| + | #* | ||
| + | # [[Switching Modes#Note about high voltages|Scintillator HVs (S0A,B and S3 in each arm)]] need to be on | ||
| + | #* Make sure the beam is off before you turn the HV on | ||
| + | #* Check that the voltages are set properly | ||
| + | # HRS CODA instructions | ||
| + | |||
| + | |||
| + | == How to analyse the run == | ||
| + | # Then type either: | ||
#* <font face="Courier"> spot_L ''run#'' </font> for the LHRS (Recommended) <p> <font face="Courier"> spot_R ''run#'' </font> for the RHRS </p> | #* <font face="Courier"> spot_L ''run#'' </font> for the LHRS (Recommended) <p> <font face="Courier"> spot_R ''run#'' </font> for the RHRS </p> | ||
#*If no run # is given, analyzes last run taken | #*If no run # is given, analyzes last run taken | ||
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/adaqfs/home/a-onl/rastersize/ | /adaqfs/home/a-onl/rastersize/ | ||
| − | + | # analyze more than 50k events | |
| − | + | # how to plot the output in a useful format | |
| − | |||
* You can get "strange printouts" of errors if you only type spot++ and the last run was for R-HRS, so it's clearer to do what is listed above than to use spot++. (note, this is because spot++ is actually spot_L). | * You can get "strange printouts" of errors if you only type spot++ and the last run was for R-HRS, so it's clearer to do what is listed above than to use spot++. (note, this is because spot++ is actually spot_L). | ||
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* Hint: Type "spot help" to learn more options. | * Hint: Type "spot help" to learn more options. | ||
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| + | [https://hallaweb.jlab.org/equipment/daq/spot.html More Info] | ||
== What do the plots mean? == | == What do the plots mean? == | ||
Need to put examples of output when we have them | Need to put examples of output when we have them | ||
Revision as of 13:38, 28 July 2019
PREX Main<< Information for Shift Takers << Shift Leader << HOW TOs
- Performing a spot++ allows us to "image" the target or by plotting the hits as a function of raster x and y current
- CASE 1 If you run with T1 trigger and target in place, spot gives a view of the target density.
- CASE 2 If you run with pulser trigger T8 spot++ gives a view of the rastered spot size.
- The steps involved in doing this measurement are
- Take the spot++ run
- Analyze the run
- Make the plots and post to the logbook
- At 20 nA the BPM plots look funny (= no signal)
- In case 1 or 2 above, the most important plot is on the first page, titled "beam on target y vs x", for example:
https://logbooks.jlab.org/system/temporary/FADC_prex_21079.pdf
How To Take a spot++ run
- Log into the a-onl account
- ssh –X aonl@aonl2 –l a-onl
- If part of a Beam Recovery procedure, make sure you have taken a CODA run in counting mode for the LHRS
- Monitoring the beam positions
- Scintillator HVs (S0A,B and S3 in each arm) need to be on
- Make sure the beam is off before you turn the HV on
- Check that the voltages are set properly
- HRS CODA instructions
How to analyse the run
- Then type either:
- spot_L run# for the LHRS (Recommended)
spot_R run# for the RHRS
- If no run # is given, analyzes last run taken
- spot_L run# for the LHRS (Recommended)
- Plots should pop up after a few seconds
- When prompted, type y or n to upload the plots to the Elog (or not)
- output file goes to:
/chafs1/work1/spot/
- (For experts) macros, source codes, DB files are at:
/adaqfs/home/a-onl/rastersize/
- analyze more than 50k events
- how to plot the output in a useful format
- You can get "strange printouts" of errors if you only type spot++ and the last run was for R-HRS, so it's clearer to do what is listed above than to use spot++. (note, this is because spot++ is actually spot_L).
- Hint: Type "spot help" to learn more options.
What do the plots mean?
Need to put examples of output when we have them
BPMA y vs x: Shows the beam location at BPM A
BPMA x: Shows the number of events at each x value in BPM A
BPMA y: Shows the number of events at each y value in BPM A
BPMB y vs x, BPMB x, BPMB y: Same as above but for BPM B
Beam at target y vs x, …x, …y: Same as above for at the target
BPMA Antenna 1, 2, 3, 4: Signal at the four wires of BPM A, one for X+, X-, Y+, Y-, respectively
BPMB Antenna 1, 2, 3, 4: Same as above but for BPM B
Cavity BCMs
- Low Current running Cavity BCM nominal points
- The cavities are used in <0.5 uA running territory (for commissioning a lead target with spot ++ check)
- Bob's EPICs variable printing to terminal script:
ssh apar@adaq ~/scripts/showCav.C
