Spring 2019 Primex

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Revision as of 09:34, 18 January 2019 by Deurpam (Talk | contribs) (Run Plan)

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Draft Run Plan for the PrimEx-D Run for first few weeks

(Updated: 01/10/2019)


The goal of the experiment: extract the η rad. decay width with as high accuracy as possible.

How: from the measured absolute diff. cross sections.

The method:

  1. measure the Compton diff. cross section on 5% Be target;
  2. compare with the known theoretical cross section and extract the so-called “setup normalization constant-Be” (ideally it should be “1”, this number will be sensitive to photon flux and efficiencies of CCAL and FCAL);
  3. measure the same Compton diff. cross section on 4He target;
  4. compare with theory prediction obtained with estimated 4He target density and with the “setup normalization constant-Be”. This new number will be used to normalize our dN(η)/dθ to get the cross sections in μb/Sr.

Run Plan

  1. With empty target:
    1. Remove the LH2 target cell (if ST needs to come out then remove it also). day shift, 7am - ~4pm
    2. Checkout and calibration of CCAL 2 shifts ~4pm – 7am
  2. With Be target:
    1. Install Be target, ST possibly in w/o cabling and survey. Day shift, 7am – ~4 pm
    2. If Be-target is ready, run Compton ~5 shifts ~4pm – 7am
  3. With 4He target:
    1. Work on target, remove Be (if needed remove ST) day shift, 7am – ~4 pm
    2. If 4He target is not ready, run “Be empty” target (ST is back) 2 shifts, ~4pm – 7 am
    3. Work on target install 4He, ST cabling day shift, 7am - ~4pm
    4. Setup checkout with beam 2 shifts, ~4pm – 7am
    5. Continue work on 4He, survey day shift, 7am - ~4pm
    6. If LHe4 still empty, run “4He empty” 2 shifts, ~4pm – 7am
    7. If “empty” is finished, fill 4He target and run LHe4 Compton
    8. Prepare the setup and run for η-Primakokf ~4pm – April
    9. Keep analyzing data