Difference between revisions of "Fall 2014 Commissioning Plan"

From Hall D Ops Wiki
Jump to: navigation, search
(Beam Configuration Parameters)
(Beam Configuration Parameters)
Line 45: Line 45:
 
**  10mm thick disk of CH<sub>2</sub> (HDPE, high density polyethylene, density 0.93-0.97 g/cm<sup>3</sup> ), 0.95 g/cm<sup>2</sup>, ~1.2% R.L.
 
**  10mm thick disk of CH<sub>2</sub> (HDPE, high density polyethylene, density 0.93-0.97 g/cm<sup>3</sup> ), 0.95 g/cm<sup>2</sup>, ~1.2% R.L.
 
** 2mm thick disk CH<sub>2</sub> (HDPE)
 
** 2mm thick disk CH<sub>2</sub> (HDPE)
** 2mm thick inside a 2cm diameter area and 7mm thick outside (HDPE)
+
** 2mm thick inside a 2mm diameter area and 7mm thick outside (HDPE)
 
** 3.4mm thick graphite disk, 0.75 g/cm<sup>2</sup>, 1.8% R.L.
 
** 3.4mm thick graphite disk, 0.75 g/cm<sup>2</sup>, 1.8% R.L.
  

Revision as of 15:00, 7 August 2014

General Information

  • Goals
    • Clean tune of the electron beam into the Tagger Dump
    • Commissioning of the unpolarized photon beam
    • Commissioning of the Hall D equipment under "soft" conditions:
      • low-intensity unpolarized photon beam <10 MHz/GeV at the endpoint
      • thin solid targets instead of the regular liquid hydrogen target
      • solenoid current 1200 A instead of the nominal 1300 A
  • Schedule and Hall Availability
    • Accelerator: beam recovery and 5.5 pass beam tune to the Tagger Dump (see [1]) are scheduled for Sept 19 - Oct 3. Tagger Hall and Hall D nominally closed.
    • Oct. 4 - Oct. 9: Accelerator beam separation commissioning. Tagger Hall and Hall D open.
    • Photon beam tune and Hall D commissioning are scheduled for 3 weeks between 10-Oct and 22-Dec 2014 (tentatively 10-31 Oct) Hall D closed during the 3 weeks.
  • Expected Staffing:
    • Run Coordinator: Alexandre Deur
    • Online Shifts: 3 persons per shift, one with solenoid training.
    • Offline Shifts: at least two people looking at data written to tape.
  • Coordination Activities:
  • Activity Priority
    • High: Activity should be completed, contingencies in place for issues.
    • Medium: Desirable to complete the activity.
    • Low: Activity would be useful if time permits us to do it.
  • Activities planned for the next run in Spring 2015:
    • Installation of liquid hydrogen target.
    • Installation of diamond radiator in goniometer.
    • Running at 1300A solenoid current.

Beam Configuration Parameters

  • Energy of Beam: expected ~ 10.5 GeV
  • Beam current:
    • Electron beam tuning is done with pulsed beam 4-10 µA, duty cycle 1.5%, average current 60-150nA (see beam description here)
    • Photon beam operations: CW 50-200 nA
  • Radiators:
    • 1.5 µm Al (1.7·10-5 R.L.)
    • 10 µm Al (11·10-5 R.L.)
    • 30 µm Al (34·10-5 R.L.)
  • Collimator hole: 5 mm diameter
  • Targets. Diameter = 3.19 cm. The position of the target can be moved 12 cm downstream to 32 cm upstream relative to the nominal Hall D target position (60 cm downstream of the downstream end of the upstream solenoid endcap.)
    • 10mm thick disk of CH2 (HDPE, high density polyethylene, density 0.93-0.97 g/cm3 ), 0.95 g/cm2, ~1.2% R.L.
    • 2mm thick disk CH2 (HDPE)
    • 2mm thick inside a 2mm diameter area and 7mm thick outside (HDPE)
    • 3.4mm thick graphite disk, 0.75 g/cm2, 1.8% R.L.

Run Plan

Tune Electron Beam

Tune Photon Beam

One Week Pause in Running

Collect Beam Data for Detector Checkout

Optimize Detector Settings

Drift Chamber Alignment

Collect More Regular Data