View source for Sunday, Apr. 15: OWL Shift

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====Shift Duties====
* Take [[#Production Running|Production data]]
* If Beam has been down for longer than 3 hours:
** Perform [[#Reestablish Beam Procedure|Reestablish Beam Procedure]]
 

====Production Running====
For the remainder of the shift take 1 hour runs in the production configuration '''DVCS: Kin_48_4'''
{|
|Beam current
|15 &mu;A
|-
|Beam Energy
|11 GeV
|-
|Target
|LH2
|-
|Raster
|ON (2x3mm<sup>2</sup>) [height x width]
|-
|VDC HV (both arms)
|ON
|-
|DVCS Calo HV
|ON
|-
|DVCS Calo Angle;
|10.069&deg;
|-
|DVCS Calo Distance
| 2.5 m
|-
|LHRS Polarity
|Negative
|-
|LHRS Momentum
|3.360 GeV/c
|-
|LHRS Angle
|24.925&deg;
|-
|LHRS Q1 Current
|1916.640 (regulator '''OFF''')
|-
|LHRS DAQ Config
|DVCS
|-
|prescaleL
| PS9=1 (all others zero)
|-
|RHRS Polarity
|Negative
|-
|RHRS Momentum
|2.204 GeV/c
|-
|RHRS Angle
|48.75&deg;
|-
|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 &mu;m
*** 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 [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]
*** 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 or whatever is on the whiteboard
*** Check that it turns '''on''' in the scope, and check Raster GUI to confirm 2x2 setting
** Ask MCC for 5 &mu;A beam
*** Run spot_L as explained in the [http://hallaweb.jlab.org/equipment/daq/spot.html 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.