Difference between revisions of "Spring 2019 Primex"
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− | ## Remove the | + | ## Remove the LH2 target cell <strike>(if ST needs to come out then remove it also)</strike>. day shift, 7am - ~4pm |
## Checkout and calibration of CCAL 2 shifts ~4pm – 7am | ## Checkout and calibration of CCAL 2 shifts ~4pm – 7am | ||
#With Be target: | #With Be target: |
Latest revision as of 09:34, 18 January 2019
Draft Run Plan for the PrimEx-D Run for first few weeks
(Updated: 01/10/2019)
Overview
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:
- measure the Compton diff. cross section on 5% Be target;
- 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);
- measure the same Compton diff. cross section on 4He target;
- 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
- With empty target:
- Remove the LH2 target cell
(if ST needs to come out then remove it also). day shift, 7am - ~4pm - Checkout and calibration of CCAL 2 shifts ~4pm – 7am
- Remove the LH2 target cell
- With Be target:
- Install Be target, ST
possiblyin w/o cabling and survey. Day shift, 7am – ~4 pm - If Be-target is ready, run Compton ~5 shifts ~4pm – 7am
- Install Be target, ST
- With 4He target:
- Work on target, remove Be
(if needed remove ST)day shift, 7am – ~4 pm - If 4He target is not ready, run “Be empty” target
(ST is back)2 shifts, ~4pm – 7 am - Work on target install 4He, ST cabling day shift, 7am - ~4pm
- Setup checkout with beam 2 shifts, ~4pm – 7am
- Continue work on 4He, survey day shift, 7am - ~4pm
- If LHe4 still empty, run “4He empty” 2 shifts, ~4pm – 7am
- If “empty” is finished, fill 4He target and run LHe4 Compton
- Prepare the setup and run for η-Primakokf ~4pm – April
- Keep analyzing data
- Work on target, remove Be