Difference between revisions of "Run1 - January 2015"
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| − | + | ;[[CEBAF_MeV_Mott_Polarimeter]] | |
| − | = | + | Mott Run 1 was performed January 13-19 with physics energy KE=5.0 MeV |
| − | |||
| − | + | == [[Mott Run 1 Journal]] - Our online summary of the experiment with many useful links == | |
| − | * | + | |
| − | * | + | == [[Mott Run1 Target Thickness Study]] == |
| + | * elastic rates summary tables from January and May [[media:rates_summarytable.ods]] | ||
| + | |||
| + | == Run1 January Analysis Documents == | ||
| + | * element locations [[media:Run1_Beamlines.pdf]] | ||
| + | * MBH3D00H/V are in reality MAD3D00H/V and use MAD field maps [[media:MAD_FMAP.pdf]] | ||
| + | * chronology in different formats [[media:run1summary.txt]], [[media:run1summary.docx]], [[media:run1summary.pdf]] | ||
| + | * on-line summary spreadsheets [[media:run1database.ods]], [[media:run1database.xlsx]] | ||
| + | |||
| + | == Matt's Campaign Strategy Notes from 5/1/2015 meeting == | ||
| + | |||
| + | |||
| + | '''''Measure Asymmetry vs Target Thickness''''' | ||
| + | * Take data at 5 MeV/c (done) | ||
| + | * Measure the thickness of companion foils, our x-axis error bar (Mamun finished with measurements, Marcy completing analysis) | ||
| + | * Assess mott spectra and assign sensible cuts, energy and time (Joe working on this now) | ||
| + | * Using the cut guidance from above, analyze our runs and create the Asym vs Target Thickness plot, with statistical error bars in Y and error bars in foil thickness from step 1b (Daniel to work on this soon, with Joe's help. Batch runs favored) | ||
| + | |||
| + | |||
| + | '''''How to assign Systematic Error?''''' | ||
| + | * Review our results, hopefully we find Asymmetry was relatively insensitive to the things we varied. Still a bit vague to me, how to assign a systematic error. (Daniel will analyze and summarize results from systematic studies, group should brainstorm to assign the value) | ||
| + | |||
| + | |||
| + | '''''Extrapolate asymmetry to Zero Thickness, determine single atom Mott Asymmetry''''' | ||
| + | * What is a sensible functional form to fit data? GEANT model will tell us this. (Marty working on this now). Assign a systematic error to the extrapolation. | ||
| + | * Use our fit result of Mott Asymmetry at zero thickness and Xavier’s theoretical prediction of Sherman function to calculate beam polarization, what is the error on the theoretical prediction? (Charlie working on this now, Joe mentions this might already be on wiki) | ||
| + | |||
| + | |||
| + | '''''Assign a polarization value to our beam: Pol = P ± Stat ± Syst ± Theory''''' | ||
| + | * Joe makes the point, Asym vs Thickness at different energies can provide more confidence (in Syst uncertainty) that our functional form fit is credible. | ||
| + | * A good fit obtained for all tested beam energies, with each fit indicating the same beam polarization, like Michael did, would be a powerful validation of our "model" (could take more data in summer, Riad cautions, better to assess Run1 first) | ||
| + | |||
| + | ''Riad favors asymmetry measurements using low-Z target material, as providing more impact for Theory'' | ||
Latest revision as of 20:00, 13 August 2015
Mott Run 1 was performed January 13-19 with physics energy KE=5.0 MeV
Mott Run 1 Journal - Our online summary of the experiment with many useful links
Mott Run1 Target Thickness Study
- elastic rates summary tables from January and May media:rates_summarytable.ods
Run1 January Analysis Documents
- element locations media:Run1_Beamlines.pdf
- MBH3D00H/V are in reality MAD3D00H/V and use MAD field maps media:MAD_FMAP.pdf
- chronology in different formats media:run1summary.txt, media:run1summary.docx, media:run1summary.pdf
- on-line summary spreadsheets media:run1database.ods, media:run1database.xlsx
Matt's Campaign Strategy Notes from 5/1/2015 meeting
Measure Asymmetry vs Target Thickness
- Take data at 5 MeV/c (done)
- Measure the thickness of companion foils, our x-axis error bar (Mamun finished with measurements, Marcy completing analysis)
- Assess mott spectra and assign sensible cuts, energy and time (Joe working on this now)
- Using the cut guidance from above, analyze our runs and create the Asym vs Target Thickness plot, with statistical error bars in Y and error bars in foil thickness from step 1b (Daniel to work on this soon, with Joe's help. Batch runs favored)
How to assign Systematic Error?
- Review our results, hopefully we find Asymmetry was relatively insensitive to the things we varied. Still a bit vague to me, how to assign a systematic error. (Daniel will analyze and summarize results from systematic studies, group should brainstorm to assign the value)
Extrapolate asymmetry to Zero Thickness, determine single atom Mott Asymmetry
- What is a sensible functional form to fit data? GEANT model will tell us this. (Marty working on this now). Assign a systematic error to the extrapolation.
- Use our fit result of Mott Asymmetry at zero thickness and Xavier’s theoretical prediction of Sherman function to calculate beam polarization, what is the error on the theoretical prediction? (Charlie working on this now, Joe mentions this might already be on wiki)
Assign a polarization value to our beam: Pol = P ± Stat ± Syst ± Theory
- Joe makes the point, Asym vs Thickness at different energies can provide more confidence (in Syst uncertainty) that our functional form fit is credible.
- A good fit obtained for all tested beam energies, with each fit indicating the same beam polarization, like Michael did, would be a powerful validation of our "model" (could take more data in summer, Riad cautions, better to assess Run1 first)
Riad favors asymmetry measurements using low-Z target material, as providing more impact for Theory