[Halld-pid] Time-of-Flight Meeting Minutes, June 6, 2014

[Mark Ito]

People,

Find the minutes below and at 
https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_June_6,_2014#Minutes 
.

   -- Mark
___________________________________________

GlueX TOF Meeting, June 6, 2014
Minutes

    Present:
      * FSU: Paul Eugenio, Sasha Ostrovidov
      * JLab: Hussein Al Ghoul, Eugene Chudakov, Mark Ito (chair), Sascha
        Somov, Beni Zihlmann

Review of Minutes from May 22

    We looked at the [21]minutes from May 22. Hussein told us that the HV
    GUI now reports when the voltages are ramping up or ramping down.

TOF Trigger

    Sascha S. brought us up to date on the status of a TOF trigger.
      * For bring the system up with cosmics, the closest detector is the
        FCAL, but an FCAL trigger will likely not help much. A trigger with
        external scintillator counters will likely not have good coverage
        of the TOF. We would like to have a TOF self-trigger of some sort.
      * A total energy trigger, like that used for the FCAL is not hard to
        implement. That will be the first step.
      * Sascha showed a [22]slide describing a TOF trigger suitable for
        calibration triggers when we have beam. A 32-bit word is output
        from the CTP, 16-bits per layer. Each bit indicates whether there
        was and end-to-end coincidence in any of a group of counters.
      * We discussed getting the read-out going. There are three TOF DAQ
        crates installed. The flashes have been read-out, but not all three
        crates together. Sascha S. will have time to turn to this effort
        next week.
      * Sasha O. asked about scalers. Sascha S. described our two options
          1. scalers in the FADC, part of the read-out
          2. scalers in the discriminator, available via EPICS
                o We need to ask Hovanes Egiyan about the status of these
                  scalers.

    Paul and Sasha plan to travel to JLab to work on the DAQ, most probably
    the week after next.

Installation Update

    Hussein has been looking at PMTs with the scope, both ends at a time,
    triggering on one and looking at the other. He set the maximum voltages
    (hard and soft) at 1800 V and the set voltage at 1200 V. No light leaks
    have been found so far. He has found some cabling anomalies. He gave
    the update.

Hussein's Update

    I started checking the modules for possible light leaks and cabling
    problems. Below is an image of the tested modules so far. All modules
    in the horizontal plane have been tested and problems were resolved.
    Keep in mind that TOF-N and TOF-S correspond to modules in the
    horizontal plane (Y), TOF-UP and TOF-DW correspond to modules in the
    vertical plane.

    [23]Testing1.JPG

Software Discussion

    We tried to identify issues in the TOF software.
      * Beni noted that the black plastic covering the FCAL and the Lexan
        sheet used for light pulsing of the FCAL are not in the geometry.
      * Beni also noted that the iron frames are not in the geometry. These
        should be added.
      * Beni thought that the process of taking raw EVIO data and
        converting it to physical quantities likely needs work. We need to
        talk to David to get the current status.
      * Sasha O. pointed out that the calibration software still needs to
        be developed.

References

   21. 
https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_May_22,_2014#Minutes
   22. https://halldweb1.jlab.org/level-1/algorithm/tof_cluster.pptx
   23. https://halldweb1.jlab.org/wiki/index.php/File:Testing1.JPG

-- 
Mark M. Ito, Jefferson Lab, marki at jlab.org, (757)269-5295