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RC phone: 757-876-1787
Crew chief: x7045
Operator 1: x7046
Operator 2: x7047
GMn Contact Information
Shift Schedule
Shift checklist
Shift Checklist How Tos
Hall A Phone Book
SBS Shifters Wiki Info
HOW TOs for shift crew
Expert Tools
Daily RC Meetings
<< SBS Main

This is the place for task-specific instructions like rebooting ROC XX, starting the High Voltage GUI or bringing up the Alarm Handler.


[Stopping and starting a run]

To monitor the disk usage, use the script "diskmon" on adaq@adaq1. This will show the fractional disk usage on each of the three disks, updating every two minutes. If the disk fraction is over 95% for the present output disk, contact Alexandre to have him change output disk.

Checking total event number for past run: You can check the number of events from a past run in a terminal:

ssh -Y a-onl@aonl1
cd gmn
./ *run number*

HV Controls

Most detector HV is controlled through the main gui. To access this:

  • Log into aslow@adaqsc
  • execute go_hv

This will open the HV GUI which will have buttons for each of the detectors. Shift workers can only turn HV on or off. Never change the HV numbers.

Shift Checklist Guide

Shift Checklist HowTos

Setting prescales and trigger

The Trigger Supervisor (TS) makes all triggers available at any time. The triggers that actually are included in the datastream are controlled by the prescale factors set at run time. To set the prescales, from any terminal on an hadesk computer log in to either adaq1 or adaq2 as follows:

ssh -Y sbs-onl@adaq1

Trigger supervisor (TS) inputs and corresponding prescales are shown in the table below. Note that PSX=-1 turns off trigger X. Otherwise, the prescale factor is approximately 2^PS (or really 1+2^(PS-1) )

Trigger # Prescale # Signal
T3 PS3 BB && HCAL Coinc
T5 PS5 GRINCH Pulser
T7 PS7 BBCAL Lo (cosmics)
T8 PS8

For data-taking, the normal prescale settings are: PS1=0 PS6=0 all other PSn= -1, if GRINCH data is not needed, or PS1=0 PS6=0 and PS6=4

PS1=0 allows the BB-shower to trigger the DAQ.

PS6=0 allows a DVCS pulser (normally set to 10 Hz), which triggers the HCal LED-calibration system, to trigger the DAQ.

PS5=4 reduces the GRINCH LED pulser from 100 Hz to roughly 10 Hz.

If you suspect the DVCS pulser for the HCal LEDs is not set to 10 Hz, (eg. beam-off rate is not 30 Hz or 40 Hz, as expected, from the 20 Hz dead-time monitor(EDTM) and the 10 Hz of HCal LED events and 10 Hz of GRINCH LED, if enabled.) then, from any window logged on as adaq or sbs-onl:

ssh -Y daq@enpcamsonne
cd test_fadc

This will launch a GUI. Your terminal screen should indicate the last setting of the rate. If it's not 10 Hz, or if you don't trust it. Click "Load DVCS Pulser Library" then click "Initalize DVCS Pulser" then click "Enable Output Channels". This will stop the pulser. Now click on the rate you want, usually 10 Hz.

EDTM instructions at

Analyzing the data

Instructions for shift crew

  • 1) Login to a-onl@aonlX (X=1, 2, 3, 4)
  • 2) once logged in, type gosbs => this takes you to the directory where the analysis should be done, and sets up the correct environment variables.
  • 3) FIRST: Check first 10,000 events by running ./ runnum 10 where runnum is the run number you want to analyze.
  • 4) SECOND: Repeat steps 1) and 2) in another terminal, and then type ./ runnum 50 with runnum the run number you want to analyze;
  • Steps (3) and (4) respectively analyze the first 10,000 and 50,000 events and produce plots that need to be checked.
  • 5) Please review all produced plots of each GUI, and click on "Exit GUI", this will pop the next GUI.
    • Example plots and instructions for understanding what to look for in HCal summary plots are here. Note: Compare the example plots with your 50k replays, and use the written explanations if there are discrepancies.
  • 6) After you're reviewed all plots, they will be saved as PDFs. YOU will be prompted in the terminal to answer (y/n) to post the plots in the HALOG. Ordinarily you will always answer yes ("y"), unless something went wrong with the replay.
  • Once per shift run a large replay of one LH2 run and one LD2 run that has at least 5M events.
  • To do this run ./ runnum
    • Run this as soon as the CODA run ends, so it finishes before the data gets moved to tape.
    • This will open several terminals and start replaying a large amount of data and may take up to 3 hours to finish.
    • NEVER run this command twice at the same time, always wait for one session to finish analyzing
  • Review the plots and post them to the HALOG just like the other replays.

If instructed by RC/run plan to replay a different number of events, follow the same instructions as above, substitute step 3) with:

  • ./ runnum nevents with runnum (integer) the run number you want to analyze and nevents (integer) the number of events to analyze (in thousands).

Monitor and Control GUIs

Most beam/accelerator related GUIs are accessible via jmenu. To bring up jmenu log in from a Counting House computer as adaq@adaq1 then type "jmenu" at the command prompt. Alternately you can access jmenu via the OPS account "hacuser", for example by running ssh -X 'jmenu' which will require a password unless you are logged in as adaq on one of the adaq machines. The jmenu search feature is pretty good at finding relevant GUIs. Use "halla" in your search to include only variables relevant to Hall A.

Opening Specific jmenu GUIs

Bringing Up Main GUIs

To bring the main GUIs we want to monitor on the TV in the counting house (hatv1), in a terminal type:

ssh -Y aslow@adaqsc

Now the VNC service is running. We can connect to these on hatv1. In a terminal on hatv1 sign in as aslow by typing ssh -Y aslow@hatv1, then type vncviewer (see sheet in CH for passcode). Minimize the terminal now to prevent other users from inadvertently killing all the VNC screens. This will bring up a window with icons for all VNC viewer windows, each one sized specifically for the GUI that it is intended to show. Click each icon to start the vncviewer for that GUI, then inside the vncviewer bring up a terminal and type:

start_tool_screens [option]

where [option] is:

  • VNC window 1: GeneralTools (accelerator overview)
  • VNC window 2: HallATools (LHRS, beam line, gas systems, etc)
  • VNC window 3: Raster
  • VNC window 4: BB (BigBite magnet current, voltage, etc)
  • VNC window 5: SBS (Super BigBite magnet current, magnetic field, and corrector magnets)
  • VNC window 6: Beam (beam energy, trajectories, positions)

Note: the options are: [GeneralTools, HallATools, Raster, BB, SBS, Beam]

Resize screens to your liking.

Bringing Up Scaler GUI

To bring up the Hall A Scaler GUI, which displays the scalers from the BigBite SHower Trigger sums, beam line, and trigger, ssh to a-onl@adaqX (X = 1, 2, 3, etc) type:


Then type ./xscaler SBS or ./xscaler Left.

Plotting EPICS variables with MyaPlot or LivePlot

For more information see Strip Chart

  1. From the jmenu GUI select Plots>>MyaPlot or Plots>>LivePlot
  2. Type into the plot the name of the EPICS variable(s) you wish to view. If you can't recall the name, you can always search jmenu for a GUI where such a variable might be displayed. For example, the Hall A Moller target position can be obtained from jmenu by searching for "halla moller target". Clicking the middle mouse button on the control or display variable located on the GUI copies the variable name into the buffer. Middle clicking again on the MyaViewer where the EPICS variable is entered will paste it into the plot.

Procedure for Ramping the BigBite Magnet

The steps to ramp the BigBite magnet are as follows. The nominal current is 750 A. The nominal polarity is NEGATIVE.

  1. Obtain permission from the Run Coordinator to ramp the BB magnetic field.
  2. Make a post in the HALOG indicating that the BigBite magnetic field will be ramped to the desired current setting.
  3. Bring up the BigBite operational GUI. From any adaq machine, type start_control_screens BBctrl
  4. In the GUI, in the SETPOINT field, type the desired current value and press the enter/return key.
  5. Confirm that the READBACK field reports desired current value
  6. Make a follow-up HALOG post indicating that the BB magnet ramp is complete. Include a screenshot of the GUI in the post.

Ramp Magnet to 0 before powering off. Always have magnet off when switching polarity. Nice explanation is here

Hall Transition Procedures

REMINDER: The Run Coordinator will work with the Hall A Work Coordinator (Jessie Butler) to implement a hall transition.

The Super BigBite (SBS) magnet produces large fringe magnetic fields. When a radiation survey is performed, the RadCon team will use devices that can be compromised by magnetic fields, yielding incorrect readings. In magnetic fields stronger than 30 Gauss, ferrous materials like steel hand tools and other devices will experience a magnetic force and have the potential to become projectiles which can damage equipment and possibly cause serious injury to personnel. To mitigate this risk, Ops/Accelerator will use their procedure to ramp the SBS magnet and the corrector magnets down to zero current prior to personnel entering the hall under controlled access. We will additionally ramp the BigBite magnetic field down to zero current when personnel need to enter the Hall.

Procedure for Hall Transition to Controlled Access

The steps to ramp the BigBite magnet to zero field are as follows:

  1. Obtain permission from the Run Coordinator to ramp the BB magnetic field down to zero.
  2. Call MCC to confirm that they will ramp down the SBS magnet and communicate that you will ramp down the BB magnet.
  3. Make a post in the HALOG indicating that the BigBite magnetic field will be ramped to zero.
  4. Follow the directions above to ramp the BB field down to zero current.
  5. Make a follow-up HALOG post indicating that the BB magnet is at zero current. Include a screenshot of the GUI in the post.

Procedure for Hall Transition to Power/Beam Permit

To prepare the hall to receive beam and take data, we need to ramp the SBS and BB magnets to their full nominal currents. For SBS, the current is 2100 A. For BB, the current is 750 A. Ops/Accelerator will ramp up the SBS magnet and corrector magnets using their procedures. We ramp up the BigBite magnet with the following steps:

  1. Obtain permission from the Run Coordinator to ramp the BB magnetic field to its nominal current.
  2. Call MCC to confirm that they will ramp up the SBS and corrector magnets and communicate that you will ramp up the BB magnet.
  3. Make a post in the HALOG indicating that the BigBite magnetic field will be ramped to full field.
  4. Follow the directions above to ramp the BB magnet to 750 A.
  5. Make a follow-up HALOG post indicating that the BB magnet is at full current. Include a screenshot of the GUI in the post.

Making a Halog entry

You can either

  1. From a terminal on any of the desktop computers type "halog" and fill out the fields. You can include screenshots and attachments if useful.
  2. Navigate to the HALOG click "Add Content". Fill out the fields as necessary and submit it. This requires you to log in with you CUE username and password. Don't forget to log out.


There are a number of alarms that shifters must respond to in Hall A in both the Counting House and the Hall. For information on how to respond to various alarms, click the links below

  • The Fire alarm. If this sounds and danger is imminent, immediately leave the building, call 911 and notify the guard shack 757-269-5822. If danger is not imminent, call for beam off and notify the crew chief, set the experiment in a safe state (if the target is moving for example, terminate the move), leave the building as soon as possible and notify the guard shack 757-269-5822.
  • VESDA (Very Early Smoke Detection Alarms). These are used to detect fire/smoke in the experimental hall. If they go off, check the hall camera for fire and notify the crew chief and the RC.
  • Target Alarm Handler The EPICS-based Target Alarm Handler is used to service only alarms specific to critical target function such as target movement, temperature and vacuum level. It is managed by Hall A staff (Silviu Covrig, Greg Smith, Jian-Ping Chen) and can only be changed upon request.
  • HallA Alarm Handler This EPICS-based Target Alarm Handler has the same underlying mechanics as the target alarm handler and is typically used to service critical hardware like spectrometer currents. It is managed by Hall A staff (Bob Michaels) and can only be changed upon request.
  • Python Alarm Handler (Not utilized so far by GMn -- DO NOT USE) The Python-based alarm handler is administered by experts in the experiment (David Flay, Don Jones) and can be edited at our convenience to include or exclude variables and change thresholds etc.

Filling out BTA

  • Login to the BTA webpage with your CUE username. Notice the Help menu.
  • Move the mouse to "File". Don't click. Let mouse hover.
  • A dialog comes up. Select "Open Timesheet".
  • Select the Hall (A), and the shift, etc.
  • As a convenience feature, you may "Load from Epics" (button at bottom right) which automatically fills the fields. Note, the shift worker must click the little pencil-looking thing in the Edit column and MUST click the check mark that appears..
  • Note, automated numbers from EPICS works ONLY FOR PRODUCTION RUNNING with the SBS DAQ, i.e. it does not account for beam used by a variety of other tasks, such as energy measurements or HARP scans. The experimenters have final say over the numbers; you can edit the fields when you click Edit. (And don't forget to click the check mark whether you have edited or not; you MUST acknowledge.) Common sense: If the beam is used by the experiment it is ``ABU.
  • Submit on the "Signatures" tab.

Beam Line


LHRS Information


BigBite Spectrometer (BB)


All GEM procedures and trouble shooting are located in this document GEM HOW TO

  • GEM HV is controlled through the main HV GUI explained here
  • Shift crews can check gas flow here:
  • Shift crews should check the gas pressures by first logging into a-onl@aonlX (X=1, 2, 3, 4). Then


Timing Hodoscope

Preshower and Shower (BBCal): Calorimeter wiki

Super BigBite Spectrometer (SBS)


HCAL: Calorimeter wiki