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

Elastic/Inelastic region Rates

Ratio of Elastic to Inelastic Region Rates = [math]\frac{650 MHz}{20 MHz + 50 MHz}[/math] = 9.3:1 = Rate ratio for QTOR=100% / 75%

In the denominator 20 MHz = Inelastic rate and 50 MHz is the elastic rate; according to the simulation

QW_Mayers2009Sim

[math]\frac{\mbox{QTOR(8921)}}{\mbox{QTOR(7583)}} = \frac{650}{84} = 7.74[/math]

Qtor	Rate (MHz)
9367	590
9144	633
8921	650
8698	528
8475	278
8252	163
8109	131
8029	121
7806	97
7583	84
7360	78
7226	76
7137	74
7048	74
6958	72
6869	69
6780	67
6691	64
6468	58
6245	52

Using the root command below

Mps_Tree->Draw("2*qwk_md3pos.hw_sum_raw/(qwk_bcm1.hw_sum+qwk_bcm2.hw_sum)","ErrorFlag==0")

I saw

Yield of MD3 Pos in Run 9905 = 1.644E4 MD counts/BPM counts

Yield of MD3 Pos in Run 9912 = 1.143E5 MD counts/BPM counts

Giving a ratio of 6.95

If I add both bar ends

Mps_Tree->Draw("2*(qwk_md3pos.hw_sum_raw+qwk_md3neg.hw_sum_raw)/(qwk_bcm1.hw_sum+qwk_bcm2.hw_sum)","ErrorFlag==0")

I saw

Yield of MD3 in Run 9905 = 4.179E4 MD counts/BPM counts

Yield of MD3 in Run 9912 = 3.239E5 MD counts/BPM counts

Giving a ratio of 7.75

using

Mps_Tree->Draw("qwk_mdallbars.hw_sum","ErrorFlag==0")

Yield of All Bars in Run 9905 = 0.027 MD counts/BPM counts

Yield of All Bars in Run 9912 = 0.0030 MD counts/BPM counts

ratio = 8.9

There seems to be some error in the comparison.

using the Hel tree

Hel_Tree->Draw("yield_qwk_mdallbars.hw_sum","ErrorFlag==0")

Shows same results as MPS tree mdallbars tree

Elastic Aluminum Asymmetry

The Aluminum asymmetry was measured to be [math]1.61 \pm 0.16[/math] PPM

0.2 MHz/nA using warm gas target

Warm gas contribution about same size as downstream aluminum window.

To do aluminum measurement we can't use warm gas cell.

Aluminum window dilution 0.022+/- 0.002

Transverse Aluminum in Elastic

A sin wave with amplitude of about 4 PPM

You can weight the yields so the transverse asymmetry gets averaged over all octants.

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

FOM

Qtor	Meas. Rate (MHz)	Elastic Simulation	Inelastic Simulation
9367	590
9144	633
8921	650
8698	528
8475	278
8252	163
8109	131
8029	121
7806	97
7583	84
7360	78
7226	76
7137	74
7048	74
6958	72
6869	69
6780	67
6691	64
6468	58
6245	52

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

Other runs

These runs were taken 16/Mar/2011 at the tail end of the Dilution factor program. The runs of interest are:

Pedestal runs: 10797, 10799, 10802 QTOR scan runs: 10798 (8921, 8943, 8988, 9200, 9010, 9032, 9054, 9200, 8921)

               10800 (1500-6500 in +500 increments, 6700, 7000, 7300, 7600, 8000)
               10801 (8029, 8188, 8207, 8300, 8386, 8475, 8500, 8564, 8653, 8700, 8743, 8832, 8899, 8921)

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

Qtor scans

Data taken on 4/12/11 check for run numbers

N->Delta Runlist

Slug / IHWP flip	Runs	Dates	Run Summaries	Notes	Slug Plots
500004 / IN R	11505-11513	Apr. 20, 2011	Runlet plots	Qtor = 6700	Slug plots
500003 / OUT R	11496-11502,11504	Apr. 20, 2011	Runlet plots	Qtor = 6700	Slug plots
500002 / OUT L	9908	Feb. 11, 2011	Runlet plots	Qtor=6700
500001 / IN L	9903,9905,9906	Feb. 11, 2011	Runlet plots	Qtor=6700

flip

The R and L refer to the setting of the solenoid in the double Wien injector spin flipper. The first Wien orients the polarization vertically, the solenoid rotates it 90 degrees to the left or right, and then the second Wien orients in horizontally by 90 degrees so it ends up either in a positive or negative helicity state. So this is our second slow helicity flip (in addition to the IHWP IN/OUT).

IHWP

This is an insertable half wave plate which changes the circular polarization of the incident laser light used to ejects electrons off the photocathode.

IHWP(IN) Flip(R) = IHWP(OUT) Flip(L)

Slug list

https://qweak.jlab.org/wiki/index.php/N_to_Delta_Slugs

On Wednesday 4/20/11 Qweak measured the Inelastic N->Delta asymmetry using 160 uA

Run 11498 Summary Table 11498 Run 11498 -

Inelastic MD allbars Asym

HWP	Solenoid	Run	Hw_sum	block 0	block 1	block 2	block 3
IN	R	11512
Out	R	11498	-2.506 [math]\pm[/math] 0.764	-1.444 [math]\pm[/math] 1.522	-3.042[math] \pm[/math] 1.523	-2.874 [math]\pm[/math] 1.523	-2.218 [math]\pm[/math] 1.524
IN	L	9905	-1.493 [math]\pm[/math] 1.020	-1.137 [math]\pm[/math] 2.707	-0.114 [math]\pm[/math] 2.707	-8.419 [math]\pm[/math] 2.986	0.4385 [math]\pm[/math] 2.714
Out	L	9908	0.8482 [math]\pm[/math] 0.8523	1.074 [math]\pm[/math] 2.384	1.350 [math]\pm[/math] 2.839	-1.862 [math]\pm[/math] 2.817	-0.352 [math]\pm[/math] 2.392

background

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

Carbon

Run 10678: Dilution tests: 0.5% Carbon, TS trig, QTOR=6700 (score: 18)

Run 10677: Dilution tests: 0.5% Carbon, TS trig, QTOR=8921

Aluminum

10751-10769

Run 10885: DS 4% AL Date: Fri, 18 Mar 2011 13:04:55 -0500

Run 10821: DS Al 4% 30uA Date: Thu, 17 Mar 2011 08:39:43 -0500

Run 10769: DS 4% Al production Date: Wed, 16 Mar 2011 07:29:58 -0500

Run 10768: DS 4% Al production Date: Wed, 16 Mar 2011 06:21:17 -0500

Run 10767: DS 4% Al production Date: Wed, 16 Mar 2011 05:50:22 -0500

Run 10766: DS 4% Al production Date: Wed, 16 Mar 2011 04:47:55 -0500

10731-10739

Run 10739: Parity 4% DS Al, 25uA, QTOR=8921 A, 3.5x3.5 mm, HWP= IN. Date: Tue, 15 Mar 2011 07:37:22 -0500

11335 -- 6700A 4% Al HWP IN

11333 -- 6700A 4% Al HWP OUT

11331 -- 2000A 4% Al HWP OUT

11330 -- SCAN 4% Al HWP OUT

Qtor scan

10478-10495 Run 10495: 4% DS dummy coarse QTOR scan run @ 45 nA,QTOR @ 8921 A Date: Sat, 12 Mar 2011 09:29:29 -0500

QTor scan using Aluminum target

5/4/2011 - 5/5/2011 (Night shift)

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*

looking for GOOD runs in database

There is a GUI interface on cdaql4 which can be run to look at run numbers and see their quality as recorded in the data base.

On cdaql4 run

./good_for_GUI

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. The HLS tree constructs helicity differences and asymmetries for each device in the data stream.

The devices listed in each tree above are folders which have sorted the data into 4 time windows within the helicity gate.

In the MPS_Tree there is a Bock0, Block1, Block2, Block3 which measures devices at 4 intervals within the helicity pulse, Block0 is first.

Several devices in the MPS_Tree are actually folders which contain branches that are raw readout, processed readout (value is converted to a unit via a calibration constant).

Drawing tree elements

Mps_Tree->Draw("qwk_bcm1.hw_sum","ErrorFlag==0")

If you get an error try

.ls

or try going up to the file subdirectory

if you pass the filename on the command line then the file is opened under the name file(0) so

_file0->cd()

should take you to the main subdirectory.

I think using the old TBrowser(0 screws up the pointers. "cd" to the file pointer when that happens.

Creating Analysis Framework with MakeClass

http://www.hep.ph.ic.ac.uk/~villeneu/analysis/rasta.html

Get a listing of available trees/ntuples

root [9] .ls
TFile**         QwPass1_9905.000.root   QWeak ROOT file
 TFile*         QwPass1_9905.000.root   QWeak ROOT file
  OBJ: TTree    Hel_Tree        Helicity event data tree : 0 at: 0x96ce3a0
  KEY: TList    9905.000_condition;1    object title
  KEY: TDirectoryFile   mps_histo;1     mps_histo
  KEY: TDirectoryFile   hel_histo;1     hel_histo
  KEY: TTree    Mps_Tree;1      MPS event data tree
  KEY: TTree    Hel_Tree;1      Helicity event data tree
  KEY: TTree    Slow_Tree;1     EPICS and slow control tree

Create a class to analyze the Hel_Tree

root [10] Hel_Tree->MakeClass()
Info in <TTreePlayer::MakeClass>: Files: Hel_Tree.h and Hel_Tree.C generated from TTree: Hel_Tree
(Int_t)(0)

Comparing Tree to created histos

I created an analysis framework using MakeClass and pass 1 root file QwPass1_9905.000.root

Below I compare the tree entries in

Hel_Tree->asym_qwk_mdallbars_hw_sum

to filing a histogram using the analysis framework

MDall->Fill(asym_qwk_mdallbars_hw_sum);

They are identical

Now compare the histogram when you multiply the entries by 1000000.

The are identical.

So I have some faith in my analysis program to create histograms in units of PPM

Chaining

Now lets chain several files together from within the Analysis framework generated by MakeClass

In file QwPass1_11498.000.root I see 94,765 events in the Hel_Tree.ErrorFlag Tree

In file QwPass1_11498.001.root I see 94,765 events in the Hel_Tree.ErrorFlag Tree (The mean is different because they are two different time parts of the same run)

Doing the same for Hell_Tree.asym_qwk_mdallbars.hw_sum Is see the same number of events and different means

Now I chain the files using

and I see the expected 189530 events. The MDallBars asymmetry looks like

The middle spike near zero appears when there is a device error. The spike goes away when you cut on device error==0.