Qweak Delta

Expected results

The above Figure in EPS format :File:D Delta Qweak Error.eps

File:A d-delta-vs-Q2.xmgrace.txt

The above Figure in EPS format :File:Atot d Delta Qweak Error.eps

File:Atot d-delta-vs-Q2.xmgrace.txt

Media:LOI-03-105.pdf

Media:PCS_Report_4_LOI-03-105.pdf

Katherine's Table

File:Shi-Lin Zhu hep-ph-0107076 2001.pdf

first Inelastic Data

Asym -vs- QTOR

From Logbook entry https://qweak.jlab.org/elog/Analysis+%26+Simulation/254

The inelastic region of interest is expected to line up o the quartz bars when QTOR ~ 0.85 of its value for elastics.

In Feb 2011, QTOR(elastic) = 8921.

=> QTOR(Delta) = 0.85 \times 8921 = 7582

Run 9908

1 hour run with HWP OUT

https://hallcweb.jlab.org/hclog/1102_archive/110211010249.html https://hallcweb.jlab.org/hclog/1102_archive/110211020513.html

Run 9905

1 hour run with HWP IN

https://hallcweb.jlab.org/hclog/1102_archive/110210233842.html https://hallcweb.jlab.org/hclog/1102_archive/110211002416.html

Combining 2 hour of data taking

QTOR= 6700 Amps

I_{beam} = 145 \mu A

[math]A_{raw} = 1.296 \pm 0.579[/math]= Asymmetry averaged over all Main Detectors

If I assume only having 50 \mu A then I would need to take 6 hours of data to get the same statistic as above.

If I take a week of data at 50 \muA then that would correspond to 28 runs like the above.

So the uncertainty would be reduced by [math]\sqrt{28} = 5.29[/math] The measurement would have an uncertainty of 0.579/sqrt{28} = 0.1 PPM

background

Dave Mack's technical note on Qweak Background contributions and propogating their error. File:Qweak Doc 965 v1.pdf

Regression

https://qweak.jlab.org/wiki/index.php/Q-weak_Regression_Wiki_Page

Data Analysis

getting Qweak data from the Silo

jcache -g hallc /mss/hallc/qweak/rootfiles/pass0/*run number here*

Root file format

The Qweak root files contain 2 trees ( MPS_Tree and EL_Tree). As the names suggest, the MPS tree contains data from devices for each Helicity bin