Difference between revisions of "Pair Spectrometer Shift"

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(Checking PS settings)
(Checking PS settings)
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* check that the magnetic field is switched on and the magnet current corresponds to the run configuration requirements. This can be done using a magnet Slow Control GUI. If the magnet is switched off
 
* check that the magnetic field is switched on and the magnet current corresponds to the run configuration requirements. This can be done using a magnet Slow Control GUI. If the magnet is switched off
 
** make sure that the photon beam is not present in the hall, otherwise call to MCC (999) and request switching the beam off.
 
** make sure that the photon beam is not present in the hall, otherwise call to MCC (999) and request switching the beam off.
** switch on the magnet using the magnet Slow Control GUI. Press "ON' button on screen and wait until it becomes green. Switching the magnetic field on may take 10-15 minutes as the magnet degaussing procedure is involved.
+
** switch on the magnet using the magnet Slow Control GUI. Press "ON' button on screen and wait until it becomes green. Switching the magnetic field on may take 10-15 minutes as the magnet degaussing procedure is involved. After the magnet is on make sure that the current reading corresponds to that from the run configuration requirements.
  
 
*  check that the right converter is inserted in to the photon beam. This can be done using the Slow Control GUI. If the converter is not in the right position, the shift crew must call to MCC (999) and request switching the beam off. The converter can be subsequently inserted by selecting the foil number on the GUI screen and clicking on "Go' button. Green color of the button indicates that the converter is on the right spot.
 
*  check that the right converter is inserted in to the photon beam. This can be done using the Slow Control GUI. If the converter is not in the right position, the shift crew must call to MCC (999) and request switching the beam off. The converter can be subsequently inserted by selecting the foil number on the GUI screen and clicking on "Go' button. Green color of the button indicates that the converter is on the right spot.

Revision as of 17:55, 12 June 2014

The Pair Spectrometer

The pair spectrometer consists of the converter, the dipole magnet and two types of scintillator detectors: 290 high-granularity hodoscope and 16 low-granularity counters (PSC), which are used to detect e+e- pairs produced in the converter by a beam photon. The converter accommodates up to 3 thin foil targets and a wire, which will be used to study the profile of the photon beam. The magnet will be operated at 1.8 T field. Light from scintillators is detected by SiPMs and Hamamatsu H7415 assemblies for the hodoscope and PSC, respectively. The nominal operating voltage for PMTs is about 1.2 kV.

Routine Operation

Checking PS settings

Before starting the run the shift should follow the run configuration requirements and perform the following actions:

  • check that the magnetic field is switched on and the magnet current corresponds to the run configuration requirements. This can be done using a magnet Slow Control GUI. If the magnet is switched off
    • make sure that the photon beam is not present in the hall, otherwise call to MCC (999) and request switching the beam off.
    • switch on the magnet using the magnet Slow Control GUI. Press "ON' button on screen and wait until it becomes green. Switching the magnetic field on may take 10-15 minutes as the magnet degaussing procedure is involved. After the magnet is on make sure that the current reading corresponds to that from the run configuration requirements.
  • check that the right converter is inserted in to the photon beam. This can be done using the Slow Control GUI. If the converter is not in the right position, the shift crew must call to MCC (999) and request switching the beam off. The converter can be subsequently inserted by selecting the foil number on the GUI screen and clicking on "Go' button. Green color of the button indicates that the converter is on the right spot.

Interlocks

Detector Expert On Call

The individuals responsible for the operation of the Pair Spectrometer are shown in the following table.

Table: Expert personnel for the Pair Spectrometer system
Name Extension Date of qualification
Alexander Somov 269-5553 June 12, 2014
Beamline expert on call 269-xxxx June 12, 2014