Difference between revisions of "Taking MAIN detector Counting Run"
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| − | * Set the HV for DN-Quartz (MAIN) detectors in both arms to -1900V (as explained in [https://prex.jlab.org/wiki/index.php/HVgui HVgui]) | + | * Move to Ca-48 target (if you are not already there) |
| + | * Call MCC and ask for 0.3uA cw beam, ask them to set IPM1C12 to normal mode | ||
| + | * Monitor HALLA:dpp and BPM target locks stripchart, wait until the BPM locks and dpp get stablize | ||
| + | ** HALLA:dpp should be stable ~-1e-4 | ||
| + | * Make sure the raster size is 2x2 mm^2 and beam is collimator centered | ||
| + | * Turn ON Scintillators (Follow the instructions in [https://prex.jlab.org/wiki/index.php/HVgui HVgui]) | ||
| + | * Monitor the scaler GUI, the T1 rate on both arms should be ~200k | ||
| + | ** Be careful, consider the safety of VDCs --> Look into white board for VDC safe zone | ||
| + | * Turn ON VDCs ('''NOTE''': Again, make sure the scintillator rate is below 500k before turning VDC ON) | ||
| + | * Set the HV for DN-Quartz (MAIN) detectors in both arms to -1900V (as explained in [https://prex.jlab.org/wiki/index.php/HVgui HVgui]). Note: If this is a Q-square run and all the detectors (MAIN and AT) are in counting mode, ATin (RHRS) should be set to -1800 V and all other detectors should be set to -1900 V. | ||
** '''L1.1 channel in S1 (Slot1) in each arm HV GUI''' (See Image 1) | ** '''L1.1 channel in S1 (Slot1) in each arm HV GUI''' (See Image 1) | ||
| − | ** '''Important Note: Once you are done | + | ** Enable the HV channels |
| + | ** '''Important Note: Once you are done with counting Run Turn this channel OFF and set the value to 0.0''' | ||
[[File:RHRS_Quartz_HV.png|thumb|600px|right|Image 1]] | [[File:RHRS_Quartz_HV.png|thumb|600px|right|Image 1]] | ||
| − | * | + | * Make sure that the IPM1C12.XPOS and HALLA:dpp stripcharts are working |
| − | + | * Click on the HALLA:dpp stripchart to mark the time and value of dpp (Again, it should be stable ~-1e-4) | |
| − | * | + | * Take counting runs on both arms (LHRS and RHRS) at least 200k events |
| − | * Take counting runs on both arms (LHRS and RHRS) | + | * '''To analyze the runs:''' |
| − | * To analyze the runs: | + | |
** ssh -Y a-onl@aonl1 | ** ssh -Y a-onl@aonl1 | ||
** goprex | ** goprex | ||
** analyzer -l | ** analyzer -l | ||
| − | ** .x | + | ** .x setup3.C(runNumber,200000) |
| − | * To produce plots: | + | * The rootfiles are stored in /chafs1/work1/prex_counting/ |
| + | * '''To produce plots:''' | ||
** In a-onl@aonl1 machine: | ** In a-onl@aonl1 machine: | ||
** cd devi/crex/alignment | ** cd devi/crex/alignment | ||
** analyzer prex_counting/prexLHRS_runNumber_200000.root for LHRS | ** analyzer prex_counting/prexLHRS_runNumber_200000.root for LHRS | ||
** analyzer prex_counting/prexRHRS_runNumber_200000.root for RHRS | ** analyzer prex_counting/prexRHRS_runNumber_200000.root for RHRS | ||
| − | ** .x alignDS.C | + | ** .x alignDS.C (Note: if the alignment was performed with upstream detectors, need to use alignUS.C macro) |
** '''Note:''' please don't modify the macro, if you want you can copy it to your directory and modify there | ** '''Note:''' please don't modify the macro, if you want you can copy it to your directory and modify there | ||
** Look into the elastic peak and read the edge of quartz (the intersection of red and blue histograms in "Projected x on detector plane" plot) | ** Look into the elastic peak and read the edge of quartz (the intersection of red and blue histograms in "Projected x on detector plane" plot) | ||
| + | ** Often the Mean and Edge values labeled in the plot do not show accurate | ||
** Zoom in to see the precise edge | ** Zoom in to see the precise edge | ||
| − | * When you are done with taking counting data '''turn OFF''' the '''DN-Quartz (MAIN) detectors HVs''' | + | ** If everything is OK, and the HALLA:dpp during the run is ~-1e-4 the elastic peak and edge position should be the following: |
| − | *'''NOTE:''' never turn ON '''DN-Quartz''' HVs during high current production running keeping them at higher HV (they will die) | + | *** LHRS --> Elastic Peak: -0.012 m, Edge: ~-0.0305 m giving the difference ~18.5 mm |
| − | * For safety, set their HV | + | *** RHRS --> Elastic Peak: -0.0465 m, Edge: ~-0.064 m giving the difference ~17.5 mm (Note:: The US sees ~1mm more than DS from previous analysis) |
| + | *** Note:: If the fit is not working properly, carefully look into the peak | ||
| + | *** Compare with the alignment from 01/25/2020 (good alignment) [https://logbooks.jlab.org/entry/3770808 HALOG] | ||
| + | *** Also look into the latest alignment from 03/23/2020 (when LHRS has quite large acceptance) [https://logbooks.jlab.org/entry/3808562 HALOG] | ||
| + | ** If these numbers are different by more than 1 mm, monitor how HALLA:dpp is doing, also monitor the Dipole set values and readback values | ||
| + | ** If both arms are showing the shift, if any, in the same direction, it is more likely the energy is changing | ||
| + | ** If only one arm is showing the shift, if any, it is more likely due to the magnet settings in the arm | ||
| + | ** If you have any doubt, or can't resolve the issue, call expert | ||
| + | ** For every run, halog the plots. Also halog the HALLA:dpp stripchart (showing the marked value) | ||
| + | * When you are done with taking counting data '''turn OFF''' the '''DN-Quartz (MAIN) detectors, VDCs and Scintillators HVs'''. '''Note:''' If this is a Q-square run and all the detectors are in counting mode '''turn OFF''' all the MAIN and AT detectors, set the '''HV''' of '''UP-Quartz (US MAIN) and AT''' detectors for '''production settings'''. | ||
| + | *'''NOTE:''' never turn ON '''DN-Quartz and VDCs''' HVs during high current production running keeping them at higher HV (they will die) | ||
| + | * For safety, set their HV to 0.0V at the end | ||
| + | *'''NOTE:''' Remember to turn ON '''UP-Quartz and AT detectors''' before going to production | ||
Latest revision as of 23:30, 7 August 2020
- Move to Ca-48 target (if you are not already there)
- Call MCC and ask for 0.3uA cw beam, ask them to set IPM1C12 to normal mode
- Monitor HALLA:dpp and BPM target locks stripchart, wait until the BPM locks and dpp get stablize
- HALLA:dpp should be stable ~-1e-4
- Make sure the raster size is 2x2 mm^2 and beam is collimator centered
- Turn ON Scintillators (Follow the instructions in HVgui)
- Monitor the scaler GUI, the T1 rate on both arms should be ~200k
- Be careful, consider the safety of VDCs --> Look into white board for VDC safe zone
- Turn ON VDCs (NOTE: Again, make sure the scintillator rate is below 500k before turning VDC ON)
- Set the HV for DN-Quartz (MAIN) detectors in both arms to -1900V (as explained in HVgui). Note: If this is a Q-square run and all the detectors (MAIN and AT) are in counting mode, ATin (RHRS) should be set to -1800 V and all other detectors should be set to -1900 V.
- L1.1 channel in S1 (Slot1) in each arm HV GUI (See Image 1)
- Enable the HV channels
- Important Note: Once you are done with counting Run Turn this channel OFF and set the value to 0.0
- Make sure that the IPM1C12.XPOS and HALLA:dpp stripcharts are working
- Click on the HALLA:dpp stripchart to mark the time and value of dpp (Again, it should be stable ~-1e-4)
- Take counting runs on both arms (LHRS and RHRS) at least 200k events
- To analyze the runs:
- ssh -Y a-onl@aonl1
- goprex
- analyzer -l
- .x setup3.C(runNumber,200000)
- The rootfiles are stored in /chafs1/work1/prex_counting/
- To produce plots:
- In a-onl@aonl1 machine:
- cd devi/crex/alignment
- analyzer prex_counting/prexLHRS_runNumber_200000.root for LHRS
- analyzer prex_counting/prexRHRS_runNumber_200000.root for RHRS
- .x alignDS.C (Note: if the alignment was performed with upstream detectors, need to use alignUS.C macro)
- Note: please don't modify the macro, if you want you can copy it to your directory and modify there
- Look into the elastic peak and read the edge of quartz (the intersection of red and blue histograms in "Projected x on detector plane" plot)
- Often the Mean and Edge values labeled in the plot do not show accurate
- Zoom in to see the precise edge
- If everything is OK, and the HALLA:dpp during the run is ~-1e-4 the elastic peak and edge position should be the following:
- LHRS --> Elastic Peak: -0.012 m, Edge: ~-0.0305 m giving the difference ~18.5 mm
- RHRS --> Elastic Peak: -0.0465 m, Edge: ~-0.064 m giving the difference ~17.5 mm (Note:: The US sees ~1mm more than DS from previous analysis)
- Note:: If the fit is not working properly, carefully look into the peak
- Compare with the alignment from 01/25/2020 (good alignment) HALOG
- Also look into the latest alignment from 03/23/2020 (when LHRS has quite large acceptance) HALOG
- If these numbers are different by more than 1 mm, monitor how HALLA:dpp is doing, also monitor the Dipole set values and readback values
- If both arms are showing the shift, if any, in the same direction, it is more likely the energy is changing
- If only one arm is showing the shift, if any, it is more likely due to the magnet settings in the arm
- If you have any doubt, or can't resolve the issue, call expert
- For every run, halog the plots. Also halog the HALLA:dpp stripchart (showing the marked value)
- When you are done with taking counting data turn OFF the DN-Quartz (MAIN) detectors, VDCs and Scintillators HVs. Note: If this is a Q-square run and all the detectors are in counting mode turn OFF all the MAIN and AT detectors, set the HV of UP-Quartz (US MAIN) and AT detectors for production settings.
- NOTE: never turn ON DN-Quartz and VDCs HVs during high current production running keeping them at higher HV (they will die)
- For safety, set their HV to 0.0V at the end
- NOTE: Remember to turn ON UP-Quartz and AT detectors before going to production
