• Created by Unknown User (moffeit), last modified on Sep 23, 2014
September 22, 2014 Meeting
Agenda:
1) Hall B work - update: Francois
2) Neutron shielding for front end boards: Takashi ordered borated polyethylene for the neutron/x-ray shield inside vacuum - need to test its vacuum compatibility.  Clive gave me all the wire stringing tool and I am practicing wire stringing using old wire frame. Takashi

3) Target: 
Richard Cook, who showed his drawings at the last Monday meeting, has been working on updating and revising them. Whoever has the purse-strings will need to purchase carbon and polyethylene rather soon, in case of a delay in delivery. If we can use the old tungsten there will be no need to order new stuff, but it might be wise to have some on order just in case. Goodfellow can supply these things, although we have to live with whatever thicknesses are available close to what we calculate.  -Clive

4) Syncrotron radiation backgrounds: 
Since the stereo sensor intersects the middle plane at the positron side, I need to look at the geometry more carefully. However, the average SR energy is less than 1 keV at 2.2 GeV beam.  So no problem. Takashi 
5) Review discussion of beam delivery procedures: 
See beam line commissioning document - section H) 
H) Tests after beam through HPS is established, chicane currents are set and rates on halo counters are as expected.

  1. HPS target is out.

  2. Downstream halo counters ON.

  3. Verify that Fast Beam Shut off is active.

  4. SVT is retracted and voltages OFF.

  5. Park Y-wire of the harp just upstream of the first Frascati at some distance (say 300 micron) from the beam center.

  6. Run beam at nominal current(200nA) for several hours, and read and store rates of the halo counters after the wire at high frequency (say 1 - 10 kHz). This should be repeated for both beam up and beam down positions.

  7. The expected average beam trip rate is10/hour, running a shift (4hours per position) should give us good understanding of beam position stability and beam motion during the trips.

  8. This covers normal operation and beam trip situation. 

  
Ken
 
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