Difference between revisions of "Sunday, Apr. 10: OWL Shift"

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(New page: Return to List of Daily Run Plans ====Shift Duties==== <!-- * Perform extended ~20 minute Carbon Hole run (only '''once''') --> * Take Production data (see below) * If...)
 
 
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====Shift Duties====
 
====Shift Duties====
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<!-- * Perform extended ~20 minute Carbon Hole run (only '''once''') -->
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* Take [[#Production Running|Production data]]
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* Take Production data (see below)
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* If Beam has been down for longer than 3 hours:
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* If Beam has been down for longer than 3 hours, Perform Beam After Extended Downtime procedure from below
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** Perform [[#Reestablish Beam Procedure|Reestablish Beam Procedure]]
 
   
 
   
 
====Production Running====
 
====Production Running====
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====Beam After Extended Downtime====
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This procedure is to be  
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====Reestablish Beam Procedure====
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This procedure is to be run every time we recover from an extended beam down (>3 hours).
 
* Harp Scans
 
* Harp Scans
 
** Move target to HOME position (if not already there) (mask target motion!)
 
** Move target to HOME position (if not already there) (mask target motion!)
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*** If the rates are high, it may indicate the beam has an angle that causes the beam to scrape on an edge of the target
 
*** If the rates are high, it may indicate the beam has an angle that causes the beam to scrape on an edge of the target
 
**** Notify the RC
 
**** Notify the RC
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**** Ask MCC to readjust bpm positions until this angle is removed
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**** Ask MCC to readjust BPM positions until this angle is removed
 
**** When done, perform another Carbon Hole run just to be sure.
 
**** When done, perform another Carbon Hole run just to be sure.
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<!--
 
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====Extended Carbon Hole Run====
 
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This is to be performed only '''once''' and may be skipped if already performed in previous shift.
 
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* Move target to Carbon Hole position (mask target motion!)
 
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** Ensure Left-HRS momentum is ~1 GeV/c
 
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** Set Left-HRS DAQ configuration to [https://hallaweb.jlab.org/wiki/index.php/How_to_HRS_/_DVCS#Changing_from_the_.22DVCS.22_run_type_to_the_.22LHRSnew.22_run_type LeftHRSnew]
 
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*** Set prescales as ps_i = 1 for i = 1-6, and ps=0 for all others
 
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** Turn the Right-HRS VDC HV '''OFF'''
 
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** Turn the Left-HRS VDC HV '''ON'''
 
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** Turn DVCS Calo HC '''OFF'''
 
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** Ensure Raster '''ON''' at 2x2
 
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*** Check that it turns '''on''' in the scope, and check Raster GUI to confirm 2x2 setting
 
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** Ask MCC for 5 &mu;A beam
 
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** Take ~20 minute run with this setting.
 
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<!--
 
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- Calo_theta= 10.1(deg), Distance = 2.5m (from target)<br/>
 
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- LHRS=3.996 GeV/c (negative pol), angle=20.243(deg), Q1=1916.640 (readout:1900)/1600/1600 (Q1 regul.OFF)<br>
 
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- RHRS=2.101 GeV/c (negative pol), angle=48.892(deg)<br>
 
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- PreScaleR : PS1=PS2=PS3=1, && PS8=200<br>
 
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- PreScaleL : PS9 =1, + DVCS config.<br><br>
 
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- Raster : 2x2mm^2
 
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Latest revision as of 22:12, 9 April 2016

Return to List of Daily Run Plans

Shift Duties

Production Running

For the remainder of the shift take 1 hour runs in the production configuration DVCS: Kin_48_2

Beam current 15 μA
Target LH2
Raster ON (2x2mm2)
VDC HV (both arms) ON
DVCS Calo HV ON
DVCS Calo Angle; 15.185°
DVCS Calo Distance 2.0 m
LHRS Polarity Negative
LHRS Momentum 3.996 GeV/c
LHRS Angle 20.243°
LHRS Q1 Current 1916.640 (regulator OFF)
LHRS DAQ Config DVCS
prescaleL PS9=1 (all others zero)
RHRS Polarity Negative
RHRS Momentum 2.101 GeV/c
RHRS Angle 48.892°
RHRS DAQ Config RHRSadaq2
prescaleR PS1=PS2=PS3=1, && PS8=200 (all others zero)


Reestablish Beam Procedure

This procedure is to be run every time we recover from an extended beam down (>3 hours).

  • Harp Scans
    • Move target to HOME position (if not already there) (mask target motion!)
    • Turn VDC HV OFF for both arms.
    • Turn DVCS Calo HV OFF
    • Ask MCC for Raster OFF (check that it turns off in the scope)
    • Ask MCC to perform Harp Scans (on IHA1H04A and IHA1H04B)
      • Must have three peaks on each with a resolution of ~200-500 μm
      • Have seen a "shoulder" on the last peak before. May be acceptable if other 2 peaks are fine.
    • Ask MCC to make an ELOG with the results of the Harp Scans
  • Beam Centering on Carbon Hole Target
    • Move target to the Carbon Hole position (mask target motion!)
    • Ensure Left-HRS momentum is ~1 GeV/c
    • Set Left-HRS DAQ configuration to LeftHRSnew
      • Set prescales as ps_i = 1 for i = 1-6, and ps=0 for all others
    • Turn VDC HC OFF for both arms.
    • Turn DVCS Calo HV OFF
    • Ask MCC for Raster ON at 2x2
      • Check that it turns on in the scope, and check Raster GUI to confirm 2x2 setting
    • Ask MCC for 5 μA beam
      • Run spot_L as explained in the detailed instructions
      • If not centered ask MCC to move beam accordingly (check board for coordinates)
      • Repeat test with different beam position until target is centered.
  • Raster Target
    • Start the same settings as carbon hole centering
    • Move to Raster Target (mask target motion!)
    • Ask MCC for 5uA beam with Raster ON (2x2)
    • Check rates and confirm they are consistent with rates seen during HOME position
      • If the rates are low and consistent, then move on to next step
      • If the rates are high, it may indicate the beam has an angle that causes the beam to scrape on an edge of the target
        • Notify the RC
        • Ask MCC to readjust BPM positions until this angle is removed
        • When done, perform another Carbon Hole run just to be sure.
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