PVDIS How To Page

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Shift Worker Responsibilities



HAPPEX/PVDIS Data Acquisition


HAPPEX DAQ cold start (up to date as of 10-28-09)

Note: This is for HAPPEX DAQ. If you want to cold start spectrometer DAQ see Spectrometer DAQ cold start.

NOTE: After HAPPEX DAQ start, ensure that the dithering and asymmetry charge feedback is turned back on.
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Turning Dithering on/off (up to date as of 9-23-09): dithering should be on throughout the PVDIS running.

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Monitoring HAPPEX systems (up to date as of 9-23-09)

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Rebooting HAPPEX crates (up to date as of 11-09-09)

List of HAPPEX crates

HAPPEX crates
  ROC       Description      Location   IP Address   Portserver
  TS1     Trigger Supervisor   Counting Room   happex4     hatsv9 port 3  
  ROC23     CH Crate   Counting Room   halladaq6     hatsv9 port 4  
  ROC26     R-arm Detectors     R-HRS Det. Stack     happex7     hatsv10 port 5  
  ROC25     L-HRS Timing Board     L-HRS Det. Stack     hallavme14     hatsv40 port 5  
  ROC28     R-arm PVDIS     near R-HRS Fastbus     pvdis1     hatsv10 port 4  
  ROC29     L-arm PVDIS     near L-HRS Fastbus     pvdis2     hatsv4 port 5  
  ROC24     Happex Inj Crate     Injector Serv. Bldg.     halladaq19     hatsv18 port 4  
  ROC31     Qweak Injector Crate     Injector Serv. Bldg.     g0inj     hatsv18 port 5  
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Running CODA for HAPPEX DAQ (up to date as of 9-23-09)

Note: This is for HAPPEX DAQ. If you want to run CODA for spectrometer DAQ see Running CODA for spectrometer DAQ.

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Switching CODA config between Pvdis and PvdNoQweak (up to date as of Nov 9, 09)

If the CODA is in Pvdis configuration, and you start getting ROC 31 errors, it is due to the Qweak crate being hung up. If you cannot reboot ROC31 quickly, then the interest of not losing any beam time, we should simply switch over to some other configuration, preferably to PvdNoQweak configuration, which has all the crates but ROC 31.

  • Note:     How to Power-Cycling the Injector Crates via http://g0injreboot.acc.jlab.org   see Rebooting HAPPEX crates.

    To switch the configuration   (in case you cannot reboot ROC31 quickly):

  • In runControl, press Reset .

  • Click on Configuration tab, and select PvdNoQweak

  • Click on Download tab.

  • If later on, ROC 31 is rebooted, and we want to go back to Pvdis configuration, then follow the set of instructions outlined above replacing instances of PvdNoQweak with Pvdis .

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    HAPPEX/PVDIS Data Analysis


    Online Data Monitor (up to date as of 11-04-09). Click  here for a one-page summary.

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    Starting prompt analysis (up to date as of 11-04-09). Click here for a one-page summary.

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    Spectrometer


    Bringing up the Alarm Handler

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    Bringing up the HAC control window

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    Changing momentum setting of HRS <- should get updates from the techs on this for PVDIS


    Reset Q1 of Left or Right HRS <- should get updates from the techs on this for PVDIS

    This is for Q1 recovery after it trips. Never use the following instruction if Q1 works fine.
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    Target How to


    Target Important Notice:


    Target Status for PVDIS:


    Checking target temperature (for PVDIS, loop 1, LD2 target should be at 22K)


    What to do if target temperature drops fast?


    Procedure on target IOC reboot


    Alarm and Major Events

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    Spectrometer Data Acquisition


    Spectrometer DAQ cold start

    Note: This is for spectrometer DAQ. If you want to cold start HAPPEX DAQ see HAPPEX DAQ cold start.

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    Mapping of ROCs to Portserver and IP for Spectr. DAQ

            HRS-DAQ CODA Configrations 

    LeftHRS Left spectrometer DAQ on adaql3
    RightHRS Right spectrometer DAQ on adaql2

    HRS-DAQ crates
      ROC       Description      IP Address   Portserver
      ROC1     R-arm Lower Fastbus Crate   hallasfi1     hatsv3 port 2  
      ROC2     R-arm Upper Fastbus Crate   hallasfi2     hatsv3 port 8  
      TS0     R-arm VME/Scaler   hallavme2     hatsv3 port 3  
      ROC3     L-arm Lower Fastbus Crate   hallasfi3     hatsv4 port 3  
      ROC4     L-arm Upper Fastbus Crate   hallasfi4     hatsv40 port 6  
      TS1     L-arm VME/Scaler   hallavme4     hatsv4 port 7  
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    Triggers for PVDIS

    We will run the spectrometer DAQ concurrently with HAPPEX DAQ, and with VDCs off, for monitoring the detectors and the quality of PID.   Periodically we will run at lower current with VDCs on, or under other special conditions, for such things as optics or Q2 measurement, background studies, etc.

    Here are the triggers on each HRS

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    Rebooting HRS crates

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    Running CODA on Spectrometer DAQ

    Note: This is for spectrometer DAQ. If you want to run CODA for HAPPEX DAQ see Running CODA for HAPPEX DAQ.

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    Starting xscaler for HRS and for PVDIS.

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    Spectrometer Data Analysis


    Analysis for Spectrometer DAQ data

    We will run the HRS DAQ and analysis concurrently with HAPPEX DAQ and with VDCs off for the following purposes:

    Periodically there will be expert-driven runs with VDCs on for the following purposes:

  • Instructions for Podd analysis:   click here for a one-page summary.

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    Hall A Detectors


    List of Detectors (up to date as of 10-28-09)

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    Detector High Voltages (up to date as of 9-23-09)

    VNC HV server (R-HRS detectors)

    Careful: in the listing below, the counting of channel numbers starts with "0"; however, in the VNC display of "Measured Voltage", the numbers at the left of the table start counting at "1", so there is an offset of 1.

    Right Arm (Lumi Det):

    Detector Mainframe ID/Slot # Card # Channel # HV (V)
    Lumi #2 15 1 -625
    Lumi #3 15 2 -790
    Lumi #5 15 4 -780
    Lumi #6 15 5 -880
    Lumi #7 15 6 -690
    Lumi #8 15 7 -615
    Lumi #4 15 10 -1040
    Lumi #1 15 11 -505
    NOTE: These Lumi voltages are nominally for 100 uA current.

    VDC check and high voltage

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    Helicity Controls


    Changing the Half Wave Plate (up to date as of 9-23-09)

    To change the state of the insertable half-wave plate (IHWP):
    1. Inform Hall B that we are about to change the half-wave plate. If they are in the middle of the run, then ask them to inform you when their run ends. Once we get the green light from Hall B, proceed into the following steps.
    2. End the current HAPPEX run and the current Compton Run.
    3. Call MCC and ask them to change the state of the Insertable Half-Wave Plate (IHWP) from In to Out or Out to In as appropriate.
    4. When you see the state of the IHWP change in the HAPPEX feedback monitor, type in an xterm (logged in as apar, make sure to log in with the argument -Y):
           flipper
    5. The new setpoints should now appear in the HAPPEX feedback monitor.. ingeneral the Rotatable Half-wave Plate (RHWP) takes a minute or two to change, but HAPPEX III uses the same RHWP position for both HWP states.
         DO NOT START A NEW RUN UNTIL YOU HAVE VERIFIED THE NEW SETPOINTS.
    6. Start a new HAPPEX run and a new Compton Run.
    7. Make a halog entry, saying you've changed the IHWP, and include a screen capture of the HAPPEX feedback monitor (the "runbird" GUI).
    8. Write the new half-wave plate configuration on the white board.

    Below is a sample of what the output looks like (from flipper).

    [apar@adaql6 ~]$ flipper

    ****************************************

    Only run this program when the IHWP change has
    already been made. If not, please Ctrl-C out now!

    Current slugnumber = 4
    Increment slugnumber? (Y/N)
    Y
    New slugnumber = 5

    Current IHWP = OTU
    Desired Settings for IHWP = OUT
    Hall-A IA = 4.79
    Hall-C IA = 5.00
    PC Pos = 8.100
    PC Neg = 6.610
    RHWP = 1200
    Current settings (to be changed)
    Hall-A IA = 4.79
    Hall-C IA = 5.0
    PC Pos = 8.575
    PC Neg = 6.125
    RHWP = 1200
    Writing the current seetings to file /adaqfs/halla/apar/feedback/IHWP.IN for the next flip back.
    Performing Flip to IHWP = OUT settings
    Halfwave plate OUT, Slug 5

    Done... Please verify the new setpoints in the HAPPEX Feedback Monitor.

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    PITA Scan (up to date as of 11-14-09)

    To measure the Polarization Induced Transport Asymmetry (PITA) slope:
    1. End the current PVDIS run and the current Compton Run.
    2. Check the status of the IHWP (IN or OUT), and set it to the state desired.
    3. Turn off the HAPPEX feedback monitor by typing
           feedback off
      in an xterm (logged in as apar). You should check that the feedback status is indeed off on runbird.
    4. Set the PC voltages appropriate for the IHWP setting. To set the voltages, open Hall Parity Controls from the Gun/Laser in the Accelerator Main Menu. We are using GUN2 currently. The voltages should be set for GUN2: PC (PITA) POS and GUN2: PC (PITA) NEG appropriately. Check the run-sheet from the previous runs to make sure the voltage you have is correct for the current IHWP setting.
      If for some reason, you are not able to change the voltages on the Hall Parity Controls , call MCC and ask them to do so!
    5. Start greenmonster from apar@adaql1 by typing greenmonster.
    6. Go to the ScanUtil tab, and click on NOT CLEAN. Set the values on Set Point 1 and Set Point 2 to 0 . Click on Set Values, and check that the set points are indeed set to 0 by clicking on Check Status .
    7. Start a new PVDIS run.
    8. After about 200 events click on CLEAN .
    9. After about 10000 GOOD events (beam trip events are not GOOD events), click on NOT CLEAN .
    10. Set the PC (PITA) POS to the previous value + 1 and PC (PITA) NEG to the previous value -1 . For instance, if the previous POS/NEG were 8.5/6.2 , the new values should be 9.5/5.2 .
    11. Set the values on Set Point 1 to +60 . Click on Set Values, and check that it is set to +60 by clicking on Check Status .
    12. Click on CLEAN .
    13. Repeat steps 9-12 , but setting the voltages in the opposite direction. The new set points should be POS/NEG 7.5/7.2 , and Set Point 1 at -60 for the example above.
    14. After about 10000 GOOD events , end the PVDIS run, and run the prompt analysis in apar@adaql4 by doing gopan, prompt runnumber .
    15. After the prompt replay is done, run hapPITA.C gui by typing gopan, pan, then
      .x lmacro/hapPITA.C(runnumber)
    16. Make a halog entry with the PITA slope, IHWP status, run # and the output plot of the gui with the PITA slope. Here is a typical PITA plot.
    17. Write the half-wave plate configuration on the white board.
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    HAPPEX Charge Asymmetry Feedback (up to date as of 9-23-09)

    For a detailed description of the HAPPEX Charge Asymmetry Feedback, look at Bryan Moffit's entry from transvertisy.
    1. The only thing that needs to be changed after each PITA/IA scan is the feedback slope, which is done in the file panFFB.db in ~/feedback/ in apar account.
    2. To turn charge feedback on, type feedback on
    3. To turn charge feedback off, type feedback off
    4. The charge feedback status should be checked in rundirb , which can be brought up by typing rundird .
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    Miscellaneous


    Bringing up the Beamtime Counting Table

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    Plotting time dependences of EPICS variables

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    Printing in the counting house

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    Starting HALOG (up to date as of 9-23-09)

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    Starting spot++ and checking the raster

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    Other Problems


    If you can't solve a problem

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    HAPPEX Home


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