Difference between revisions of "Beam Line Detectors Shift"

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shift crew members. During data taking, the hodoscope will  
 
shift crew members. During data taking, the hodoscope will  
 
be used to monitor the beam stability.
 
be used to monitor the beam stability.
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== Routine operation==
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A shift taker will need to monitor the environmental and base sensors through a GUI interface. The darkroom is equipped with 4 sensor boxes, each reads the temperature, humidity, and light conditions inside the darkroom. Each of the 2800 bases are equipped with temperature, high voltage, and current sensors. The following instructions are for non-experts during routine operation.<font color=red> Operations beyond what is specified here shall only be performed by the system expert or under his/her direction. </font> If the expert directs an operation outside the  ones described here, a specific note must be entered into the log book.
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== Voltage Settings and Control ==
 
== Voltage Settings and Control ==

Revision as of 17:39, 11 June 2014

Tagger Hodoscope

The tagger hodoscope consists of 218 scintillator counters which are installed behind the focal plane of the tagger magnet. The light produced in each counter is detected using Hamamatsu R9800 PMTs which are instrumented with JLab's custom designed dividers and divider-based amplifiers. The PMTs will be operated at around 950 V. The hodoscope will be used for tuning the orientation of the radiator crystal by measuring the photon beam energy spectrum. This procedure will require involvement of experts and will not be performed by shift crew members. During data taking, the hodoscope will be used to monitor the beam stability.

Routine operation

A shift taker will need to monitor the environmental and base sensors through a GUI interface. The darkroom is equipped with 4 sensor boxes, each reads the temperature, humidity, and light conditions inside the darkroom. Each of the 2800 bases are equipped with temperature, high voltage, and current sensors. The following instructions are for non-experts during routine operation. Operations beyond what is specified here shall only be performed by the system expert or under his/her direction. If the expert directs an operation outside the ones described here, a specific note must be entered into the log book.


Voltage Settings and Control

All PMT voltages and trip currents will be preset by the detector experts and will be switched on by the shift crew by clicking 'All HV' button on the GUI interface. If any of the bases fail to set their high voltage a non-expert will first retry clicking 'All HV'. If the problem persists the expert should be called.


Expert personnel

The individuals responsible for checking that the Hodoscope is ready to take data and setting its operating parameters are shown in following table. Problems with normal operation of the hodoscope should be referred to those individuals and any changes to their settings must be approved by them. Additional experts may be trained by the system owner and their name and signature added to the document residing in the Hall D Counting House.

Table: Expert personnel for the Hodoscope system
Name Number Date of qualification
Alexander Somov (757) 269-5553
Franz Klein