Beam and Hall checks

From PREX Wiki
Revision as of 11:55, 27 June 2019 by Sanghwa (Talk | contribs) (Hall Status)

Jump to: navigation, search

In the process of editing and updating this page. Please contact Juliette Mammei with questions or suggestions.

PREX Main<< Information for Shift Takers << Shift Leader << Shift Checklist

Figure 1 - Alarm handler window when there is a red alarm. If nothing is alarming, it would be grey.
Figure 2 - The beeamline section in the Hall A Tools window.
Figure 3 - A picture of the scope when the raster is off. This would be BAD if beam were on!
Figure 4 - Picture of the BCM temperature readout in the computer room.
Figure 5 - Snapshot of the Fast Feedback Controls when the FFB is OFF.
Figure 6 - The gas section in the Hall A Tools window.
Figure 7 - Camera and alignment info in the Hall A Tools window.
Figure 8 - The VESDA panel in the counting house.
Figure 9 - Where you can find the camera display and the controls in the counting house.
Figure 10 - The camera controls.
Figure 11 - The Moller Polarimeter Temperature Screen with optimal values.

Alarm Handler

  • VESDA System OK? (see Figure 8)
    • VESDA is the smoke/fire detection and alarm system
    • Check the Hall A VESDA Console on the wall behind the door
    • Every light should be green and in the minimum lowest alert setting.
  • Is alarm handler running on hacweb7?
    • On hacweb 7, you should see a window in the upper right corner of the screen
      • Look first in the "Alarm Handler" desktop to see if it is there
      • Check all the windows if not
    • If not open, see Alarm Handler
  • Is the volume up on hacweb7? (both hardware and software)

Hall A Tools and related menu screens


  • Visual Hall Inspection OK? (see Figure 9)
    • Make sure to move the camera around and zoom in (See Figure 10)
    • when complete, zoom all the way back out
  • Beam Energy (MeV) (see Figure 2)
  • Beam Current (µA)
  • Current Target (45 degree ladder/90 degree ladder)
    • See Target GUI on Target computer
    • Or JMenu -> Search for Target GUI -> "Hall A Target Lifter" and it has the same information (as well as raster and other useful information)
  • Are the Hall A Target position slow locks functioning? - Should be locked during Parity Production
    • JMenu -> Search for Orbit Lock -> Select "Orbit Locks Normal View"
    • If HallATGT is Green and Lock Status = Running then the slow locks are enabled
  • Beam Position Monitor (BPM) X/Y (mm) A
  • Beam Position Monitor (BPM) X/Y (mm) E (Called BPM B in Hall A Tools)

  • Downstream raster (labelled B or 2, US raster is not in use) on?
    • Check the Oscilloscope in Counting House Middle Room: Yes/No
    • when raster is off, looks like Figure 3
    • when raster is on, something like halog 3654466
  • Raster size (x vs. y in mm)?
    • You can also check with the JMenu -> Hall A Fast Raster screen
  • Fast feedback (FFB) on? Yes/No - should be on during Parity Production
    • The easiest check is to look at the FFB information in bottom left corner of Hall A General Tools
    • An additional way to check whether the FFB is on or off:
      • in a terminal window, type JMenu
      • search for "fast"
      • Choose "Fast Feedback Control" (see Figure 5, which shows the upper left corner when FFB is OFF)
      • The status is indicated by the button that is depressed (OFF and RUN in the figure)
    • FFB should be ON during normal production running!
    • However, FFB will be paused during beam modulation
  • BCM temperature (K) (PV, PS, Thermocouple)
    • If these differ by +/-.5 from (110.0, 110.0, 115.0) (Fahrenheit) contact RC and halog
    • These temperature readbacks are located in the middle DAQ room, in rack CH0B06 (far left) at the very top (see Figure 4)
    • It is important that these temperatures stay stable within 0.5 Fahrenheit or else the BCM current readout will become uncalibrated
  • Accelerator Arc Beam Energy NMR locked?
    • Go to "Energy Lock GUI" from JMenu -> Applications section -> "Energy Locks"
    • Verify if the box locked is ON/OFF - should be on during Parity Production
    • If the 3 "OR", "1A", and "2A" lights are green then the energy is locked

Hall Status

  • Are the Compton Background Rates sufficiently low (<10kHz)?
    • JMenu -> Plots -> MyaPlot -> Right Click and Load a Configuration -> Select PREX in Directories -> Compton Background Rates -> Ok Move to Now
    • If you see anything above 10kHz in any of the strip charts, this is bad, and the Compton Expert on shift should be notified
  • Is the Compton DAQ running? (It should be during Parity Production)
    • Ask the Compton expert on shift
  • Is the Compton Photon Detector PMT High Voltage on? (It should be during Parity Production)
    • Look at the Low Voltage power supply, it is at the bottom of the electronics rack CH01B00 in the middle DAQ Counting House room.
    • It is a small box with a banana plug -> BNC cable plugged into it
    • The Voltage should read approximately 5.3 Volts
  • Is the Moller Polarimeter within operational temperature limits? See Figure 11 for reference and Simona's elog entry
    • The screen can be obt ained through: NewTools -> JMenu -> "Moller Polarimeter Temperature Monitor" -> Hall A Moller Temperature
    • The optimal points are: Cryocooler (T1) ~ 3K, Magnet (T2) ~3K, Magnet Lead #1 ~40K, Magnet Lead #2 ~ 40K
    • If something happens for the Moller Polarimeter, Call Simona
  • Septum current (A) and polarity? Matches whiteboard set-point?
    • JMenu -> Search for Big Bite Septum or Hall A Septum
    • Before adjusting septum please read and sign the septum OSP document (in the yellow OSP folder)


  • Pressures (see Figure 6)
    • Argon pressure (psi)
    • Ethane pressure (psi)
    • CO2 pressure (psi)

Next in checklist >> Parity Checks