CHIPS Run May-2008

CHIPS run from May 27-30.

Goals

1. Determine smallest beam spot size using JLAB flags at the zero degre port and after the 90 degree bend on the 25 MeV machine current beam line
2. Install FC and measure its performance (smallest controllable current atainable)
3. Measure background rates for positron production

Solvable Problems:

1.) JLAB would like beam spot of 1 mm. Measured 8 mm after thick window. Doug reported measuring 3 mm without thick window.

2.) Lowering beam current: 10^8 electrons/pulse desired to produce 1 positron per pulse. Perhaps slits can solve the above problems and then localized lead shielding to reduce backgrounds.

3.) Beam position monitoring. Flags from JLab have arrived Brett will look into installing.

May run on IAC schedule for 27,28,29,30
need cameras for the flags.

Next steps after Feb run:

1.) Optimize develop beam line design. Serkan needs more input about the IAC beam properties.

2.)Proposal is to measure beam properties with flags and FCUP during May 27-30 run. (parts to install beam line flags is critical path defining the run start date).

   a.)Measure beam shape at zero degree port and after 90 degree bend
   b.) install FCUP (2 3/4 flange)
   c.) measure background rates
 
      i.) one flag has positron converter in experimental cell.
      ii.) dipole on experimental cell side
      iii.) photon veto using scintillators

3.) Future beam line

 a.) perhaps move converter target between dipole
 b.) 50 ns beam pulse may give you +/- 2 MeV spread

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