# Expected results

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

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

### Elastic/Inelastic region Rates

Ratio of Elastic to Inelastic Region Rates = = 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

Katherine's simulation results

#### John Leacock's Summer 2011 Analysis

 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

#### ROOT commands used to check rates

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

#### Rakitha's Sept 2011 Analysis

An old ELOG entry has been updated: Logbook: Analysis & Simulation Message ID: 408 Entry time: 09/19/11, 22:26 Author: Rakitha Beminiwattha Category: Analysis Status: Current Subject: Background Contribution to the Main Detector Yield

Summary for octant 1 and 5 results are given in the Table 2 and 3 respectively Background contribution for,

MD1 = 1 - ( TDC_R_MD1.TS2 times ADC_counts_MD1.TS2 )/( TDC_R_MD1 times ADC_counts_MD1 ) MD5 = 1 - ( TDC_R_MD5.TS1 times ADC_counts_MD5.TS1 )/( TDC_R_MD5 times ADC_counts_MD5 )

The ADC spectrum and correlation plot between two PMT signals for all the QTOR currents are given in the attachment 1 for MD1 and attachment 2 for MD5. The red curve is the Landau fit for the pedestal and black curve is the Gaussian fit for ADC mean channel counts.

The split yield of MD1 ADC sum due to the glue joint issue see on the Figure 4 of the attachment 1. MD5 ADC sum yield has no such effect. Around nominal QTOR currents the ADC spectrum for MD.TS lacks any pedestal counts. The pedestal contribution creeps in as QTOR currents is reduced.

Table 2: Octant 1
MD real	(MD1)				MD good(MD1.TS2)			Yield
Fractions
QTOR	Ped.					Ped.
(A)	corrected 				corrected
Mean  					Mean
Channels	Error	Rate 		Channels	Error	Rate		Good	Bkg

9200	747.30		1.89	7.98		755.90		1.89	7.61		96.48	3.52
9000	738.70		36.61	7.10		742.90		2.01	6.79		96.10	3.9
8700	596.10		2.68	6.25		603.40		2.68	5.94		96.27	3.73
8500	493.00		5.24	2.53		515.70		4.66	2.33		96.51	3.49

8300	471.10		6.40	1.57		505.80		5.54	1.38		94.33	5.67
8000	405.30		11.67	0.98		466.80		8.99	0.82		95.34	4.66
7600	302.60		16.34	0.89		413.40		10.96	0.7		107.64	-7.64
7000	352.80		15.20	0.73		395.60		12.12	0.55		83.90	16.1
6700	332.90		15.63	0.76		385.60		12.43	0.56		85.74	14.26
6500	366.20		13.55	0.64		400.30		11.56	0.48		80.53	19.47
6000	241.50		23.46	0.55		300.80		19.57	0.38		86.16	13.84
5500	149.30		38.20	0.47		230.50		28.24	0.3		100.02	-0.02
5000	124.60		11.20	0.54		204.60		8.00	0.34		102.10	-2.1
4500	66.70		13.40	0.56		136.80		11.00	0.34		123.76	-23.76
4000	-22.60		17.00	0.53		78.40		13.30	0.31		-202.57	302.57
3500	-265.00		20.60	0.56		85.60		6.40	0.32		-18.59	118.59
3000	-445.50		30.30	0.61		31.60		7.20	0.34		-4.02	104.02
2500	-544.20		42.10	0.59		-49.00		10.60	0.33		5.05	94.95
2000	-782.40		137.30	0.83		-150.80		14.30	0.49		11.44	88.56
1500	-575.30		89.30	1.88		-269.60		21.70	1.35		33.83	66.17
1000	-401.10		53.90	9.10		-353.00		38.50	7.62		73.74	26.26
Table 3: Octant 5
MD real	(MD5)				MD good(MD5.TS1)			Yield
Fractions
QTOR	Ped.					Ped.
(A)	corrected 				corrected
Mean  					Mean
Channels	Error	Rate 		Channels	Error	Rate		Good	Bkg
9200	1017.60		2.31	7.98		1038.20		2.12	7.61		97.32	2.68
9000	999.20		2.53	7.10		1022.90		2.34	6.79		97.82	2.18
8700	811.10		3.30	6.25		834.00		3.01	5.94		97.79	2.21
8500	664.70		7.05	2.53		710.80		6.15	2.33		98.66	1.34

8300	701.70		8.35	1.57		738.40		7.45	1.38		92.45	7.55
8000	620.80		14.33	0.98		681.80		11.93	0.82		90.91	9.09
7600	556.90		21.42	0.89		643.60		17.70	0.7		91.05	8.95
7000	394.60		24.42	0.73		533.70		16.42	0.55		101.20	-1.2
6700	329.40		26.38	0.76		484.70		17.87	0.56		108.93	-8.93
6500	344.00		27.61	0.64		503.00		17.11	0.48		107.72	-7.72
6000	352.20		29.01	0.55		472.40		19.61	0.38		92.78	7.22
5500	178.30		42.50	0.47		365.30		24.71	0.3		132.73	-32.73
5000	100.20		15.40	0.54		286.30		9.70	0.34		177.66	-77.66
4500	-7.60		19.60	0.56		218.90		11.20	0.34		-1737	1837.98
4000	-148.30		26.90	0.53		131.80		14.50	0.31		-51.90	151.9
3500	-331.50		34.20	0.56		20.70		16.80	0.32		-3.59	103.59
3000	-526.30		46.70	0.61		-90.90		21.00	0.34		9.79	90.21
2500	-970.20		132.10	0.59		-285.50		36.20	0.33		16.49	83.51
2000	-1395.50	164.90	0.83		-507.50		69.40	0.49		21.58	78.42
1500	-2136.80	58.80	1.88		-1024.50	13.10	1.35		34.61	65.39
1000	-1655.80	36.60	9.10		-1438.10	11.61	7.62		72.77	27.23



## Elastic Aluminum Asymmetry

The Aluminum asymmetry was measured to be 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.

## Peiqing Wang Simulation of contributions to elastic asymmetry

 Source Contributions to the Overall Det. Yield (%) f = Y/Ytot. Asymmetry A (ppb) Q2 (GeV2) Scattering Angle Theta (degree) Contributions to the Overall Asymmetry i.e. Yield-weighted Asymmetry (ppb) Acont =A*Y/Ytot. Contributions to the Overall Asymmetry (%) Acont/(-158.2) Elastic e-p (LH2 tgt.) 95.8 ±0.3 -216.53 ± 0.53 0.02452 ±0.00005 7.782 ±0.007 -207.4 ±0.5 131.1 Elastic e-Al (entrance target window) 1.609 ±0.006 1799.53 ± 3.04 0.01983 ±0.00003 6.901 ±0.006 28.95 ±0.05 -18.30 Quasi-elastic e-p (entrance target window) 0.657 ±0.004 -193.77 ± 0.74 0.02250 ±0.00007 7.363 ±0.011 -1.273 ±0.005 0.80 Quasi-elastic e-n (entrance target window) 0.018 ±0.001 -2173.93 ± 4.32 0.02467 ±0.00005 7.710 ±0.008 -0.391 ±0.001 0.25 Elastic e-Al (exit target window) 1.167 ±0.003 2106.99 ± 2.94 0.02321 ±0.00003 7.669 ±0.005 24.59 ±0.04 -15.54 Quasi-elastic e-p (exit target window) 0.581 ±0.003 -248.4 ±1.0 0.02732 ±0.00009 8.325 ±0.013 -1.443 ±0.006 0.91 Quasi-elastic e-n (exit target window) 0.0205 ±0.0001 -2670.2 ± 5.0 0.03019 ±0.00006 8.750 ±0.008 -0.547 ±0.001 0.35 Inelastic e-p (LH2 target) 0.014 ±0.001 -2220.7 ± 61.2 0.0222 ±0.0006 8.570 ±0.106 -0.311 ±0.009 0.20 Moller (LH2 tgt.) 0.16 ±0.04 -210.23 ± 51.72 0.00110 ±0.00002 6.567 ±0.900 -0.34 ±0.08 0.21 Others (e.g. beamline, collimator, shielding wall) N/A N/A N/A N/A N/A N/A Total 100 -158.2 (yield-weighted) 0.02440 (yield-weighted) 7.767 (yield-weighted) -158.2 ±0.5 100

# 877 MeV Qweak run

## Initial results

It looks like the 2 pion contamination has a positive asymmetry opposite to the one pion production asymmetry. The large uncertainties of PPM (2 hour measurement) for the two pion enhanced region (QTOR=400 A) and PPM for the delta region of interest (QTOR=4650 A) restrict making a definitive claim. The expected asymmetry is

assuming

P = 0.79
= 0.165
= -1.5ppm
= -0.14ppm

unfortunately the uncertainties prevent concluding that the multi-pion asymmetry is a factor of 10 larger than single pion and of opposite sign. Need more running at in the multi-pion region.

# 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

## Run 9905

1 hour run with HWP IN

## Combining 2 hour of data taking

QTOR= 6700 Amps

I_{beam} = 145 \mu A

= 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 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
500015 / IN L 14373- Dec. 13-, 2011 Qtor = 6700; "de-tuning" test from 14375- to try to regenerate the large background/lumi detector asymmetries.
500014 / OUT L 14365-14372 Dec. 12-13, 2011 Qtor = 6700
500013 / IN L 14341-14364 Dec. 12-12, 2011 Qtor = 6700
500012 / OUT L 14338-14340 Dec. 11-12, 2011 Qtor = 6700
500011 / IN L 14329-14337 Dec. 11-12, 2011 Qtor = 6700
500010 / OUT L 14317-14328 Dec. 11-11, 2011 Qtor = 6700 runs 14325, 14326, 14327 Pedestal runs.
500009 / IN L 14314-14316 Dec. 10-11, 2011 Runlet plots Qtor = 6700; beam 0.5 mm beam right.
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

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 Out R 11496 11498 -2.506 0.764 -1.444 1.522 -3.042 1.523 -2.874 1.523 -2.218 1.524 11499 11500 11501 11502 -2.033 0.774 -4.297 1.541 -1.970 1.541 -2.570 1.544 0.760 1.541 11504 IN L 9905 -1.493 1.020 -1.137 2.707 -0.114 2.707 -8.419 2.986 0.4385 2.714 IN R 11506 11507 11508 11509 11510 11512 11513 Out L 9908 0.8482 0.8523 1.074 2.384 1.350 2.839 -1.862 2.817 -0.352 2.392

### =Asym based on helicity pattern

 HWP Solenoid Run Hw_sum (-++-) Hw_sum (+--+) Hw_sum(-++-) block 0 Hw_sum(+--+) block 0 Hw_sum(-++-) block 1 Hw_sum(+--+) block 1 Hw_sum(-++-) block 1 Hw_sum(+--+) block 2 Hw_sum(-++-) block 2 Hw_sum(+--+) block 3 Hw_sum(-++-) block 3 Out R 11496 11498 11499 11500 11501 11502 11504 IN L 9905 IN R 11506 11507 11508 11509 11510 11512 11513 Out L 9908

## Inelastic dslumi_sum Asym

 HWP Solenoid Run Hw_sum block 0 block 1 block 2 block 3 Out R 11496 11498 1.547 0.296 1.449 0.462 1.434 0.463 1.541 0.465 1.390 0.466 11499 11500 11501 11502 11504 IN L 9905 IN R 11506 11507 11508 11509 11510 11512 11513 Out L 9908

# background

## Background Detectors During Inelastic Runs

John shows a large non-zero background during inelastic runs when IHWP/Wein=OUT/R

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)

# 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

A primative script to use MakeClass and Chaining several files

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.