Difference between revisions of "BCM"

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== Unser Calibration [2 hours] ==
 
== Unser Calibration [2 hours] ==
  
 +
<ol> 
 
<li>  The unser calibration is done using the wire and the current source in the Counting House, without beam time (any opportunistic time when there is no beam).
 
<li>  The unser calibration is done using the wire and the current source in the Counting House, without beam time (any opportunistic time when there is no beam).
 +
<li> To access to the wire current supply, in epics look for the Hall A Menu -> BCM -> Unser monitor.
 +
<li> Start CODA runs in both arm before sending any current to the Unser, Use the LHRS Clock as trigger 100.
 +
<li> Send to the wire different currents 0,5,0,20,0,40,0,60,0,80,0,100,0,5,0,20,0,40,0,60,0,80,0,100,0  (uA). Each current should be sent for at least 90 seconds.
 +
</ol>   
  
−
<li> Use the wire to calibrate the unser. To access to the wire current supply, in epics look for the Hall A Menu -> BCM -> Unser monitor.
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<table border="1"  style="width:80%">
−
<li> Send to the wire different currents 0,5,0,20,0,40,0,60,0,80,0,100,0 (uA). Each current should be send for at least 90 seconds. Record the data from the DAQ system.
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  <tr>
−
<li> The unser is a very noisy device. Therefore, the 0 (uA) are sent to subtract the local background for each current.
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    <td> Date </td>
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<li> In a graph of the current vs the frequency recorded by the DAQ, and calculate the gain of the linear fit. The offset of the graph should be nearly zero, since the local background was subtracted.
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    <td>LHRS CODA run</td>
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</ol>  
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    <td>RHRS CODA run</td>
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<li> Also start a HRS run to record the scalers during the calibration procedure, use the clock to take reasonably high data rate (LHRS Clock =100)
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    <td> Comments </td>
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<li> It is useful to have someone over in MCC to help coordinate the calibration with them.
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  </tr>
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<li> Take data on carbon target with I = 0, 3, 0, 5, 0, 7, 0, 10, 0, 15, 0, 20, 0, 25, 0, 30, 0, 40, 0, 50, 0, 60, 0, 70, 0, 80, 0 &mu;A (or as high a current as available). Each beam period (with or without current) should last 90 s. If you get a trip during a beam up period, take 90s of beam off and restart that beam up period.
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  <tr>
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</ol>
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    <td> 08/30/2018</td>
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    <td> 3305</td>
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    <td> 93298 </td>
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    <td>  </td>
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  </tr>
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</table>

Revision as of 18:21, 28 September 2018

Back to Tritium-Main

Back to Fall Installation and Commissioning

BCM Calibrations [2 hours]

Procedure:

  1. It is useful to have someone over in MCC to help coordinate the calibration with them.
  2. The target used in this calibration is irrelevant, so try to use a solid target if possible but not necessary.
  3. Start the LHRS and RHRS runs with no beam and with a clock prescale LHRS=100.
  4. Ask to mcc for the set of currents: I = 0, 3, 0, 5, 0, 10, 0, 15, 0, 22.5, 0,3, 0, 5, 0, 10, 0, 15,0, 22.5, μA. Each current should be send for at least 90 seconds
  5. Take data on carbon target with I = 0, 3, 0, 5, 0, 7, 0, 10, 0, 15, 0, 20, 0, 25, 0, 30, 0, 40, 0, 50, 0, 60, 0, 70, 0, 80, 0 μA (or as high a current as available). Each beam period (with or without current) should last 90 s. If you get a trip during a beam up period, take 90s of beam off and restart that beam up period. If you get a trip during a beam up period, take 90s of beam off and restart that beam up period.
      Date LHRS CODA run RHRS CODA run Comments
      -

      Unser Calibration [2 hours]

      1. The unser calibration is done using the wire and the current source in the Counting House, without beam time (any opportunistic time when there is no beam).
      2. To access to the wire current supply, in epics look for the Hall A Menu -> BCM -> Unser monitor.
      3. Start CODA runs in both arm before sending any current to the Unser, Use the LHRS Clock as trigger 100.
      4. Send to the wire different currents 0,5,0,20,0,40,0,60,0,80,0,100,0,5,0,20,0,40,0,60,0,80,0,100,0 (uA). Each current should be sent for at least 90 seconds.
      Date LHRS CODA run RHRS CODA run Comments
      08/30/2018 3305 93298
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