Difference between revisions of "Analysis"
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Q^2=4*2.5*Energy*sin(particle_ptr[i].trl1_theta/2)*sin(particle_ptr[i].trl1_theta/2);<br> | Q^2=4*2.5*Energy*sin(particle_ptr[i].trl1_theta/2)*sin(particle_ptr[i].trl1_theta/2);<br> | ||
X=Q/(2*(5.7-Energy)*mp);<br> | X=Q/(2*(5.7-Energy)*mp);<br> | ||
− | [[Image: | + | [[Image:vs_paddle_x.gif|200px]] |
− | + | [[Image:vs_paddle_x_1.gif|200px]]<br> | |
Used file dst26988_05.B00(Energy=5.7GeV and Torus=-2250)<br> | Used file dst26988_05.B00(Energy=5.7GeV and Torus=-2250)<br> | ||
Revision as of 20:55, 11 September 2007
EG1 run database
run summary
polarization info
Particle Identification
Electron
Cuts
Calorimeter based cuts
The distributions below represent two types of cuts applied to improve the electron particle identification (PID) using a 4 GeV electron beam incident on an NH3 target. The electron calorimeter is segmented into an inner
and an outer region. The total energy absorbed by the calorimeter system is recorded in the variable . The momentum ( ) is calculated using the reconstructed track and the known torus magnetic field. The distributions of and are shown below where both have been divided by the electron momentum and no cuts have been applied.
Without any cuts we have 181018 entries. After using the following cut
After the cut on the energy deposited into inner part of electron calorimeter, number of entries decreases by 22%.
Both cuts and
In case of using the cuts of the total deposited energy and the energy deposited into inner calorimeter number of entries decreases ~36%
summary table
The "# of triggers" columns represents the number of events which generated a signal above threshold in the calorimeter and the scintillator. The expected # of events column represents the number of reconstructed events with tracks that also make it through the cuts defined in the table.
The semi-inclusive analysis will focus on the 4 GeV and 6 GeV data which have both inbending and outbending torus settings. Specifically runs 28074 - 28579 ( 4 GeV) and Runs 27356 - 27499 and 26874 - 27198 (6 GeV)
Beam Energy | Torus Current | Begin Run | End Run | file used | cuts | # trig( | )expected # evts( | )p<3, | , (%)p>3, | , (%)||
---|---|---|---|---|---|---|---|---|---|---|---|
and | |||||||||||
1606 | 1500 | 25488 | 25559 | dst25504_02.B00 | 64% | 49.5% | 78% | 60 | 3.2 | ||
1606 | 1946 | 25560 | 25605 | 44 | |||||||
1606 | 1500 | 25669 | 25732 | dst25669_02.B00 | 64% | 49% | 78% | 226 | 10 | ||
1606 | 1500 | 25742 | 26221 | dst25754_02.B00 | 21% | 11% | 24% | 3154 | 13.3 | ||
1606 | -1500 | 26222 | 26359 | dst26224_02.B00 | 4.6% | 3% | 6.6% | 703 | 13.1 | ||
1724 | -1500 | 27644 | 27798 | dst27649_02.B00 | 4.8% | 2.2% | 5.9% | 211 | 20 | ||
1724 | 1500 | 28512 | 28526 | 159 | |||||||
1724 | -1500 | 28527 | 28532 | 93 | |||||||
2288 | 1500 | 27205 | 27351 | dst27225_02.B00 | 20.2% | 13% | 25.6% | 1647 | 16.1 | ||
2562 | -1500 | 27799 | 27924 | dst27809_02.B00 | 5.7% | 4.6% | 8.6% | 1441 | 13.1 | ||
2562 | -1500 | 27942 | 27995 | dst27942_02.B00 | 6.1% | 4.4% | 8.9% | 841 | 32.3 | ||
2562 | 1500 | 28001 | 28069 | dst28002_02.B00 | 27.8% | 13% | 29.6% | 1013 | 30.7 | ||
2792 | -1500 | 27936 | 27941 | dst27937_02.B00 | 6.7% | 5% | 9.9% | 69 | 20.6 | ||
3210 | -2250 | 28549 | 28570 | 436 | |||||||
4239 | 2250 | 28074 | 28277 | dst28075_02.B00 | 35.3% | 23.9% | 40.5% | 2278 | 19.6 | ||
4239 | -2250 | 28280 | 28479 | dst28281_02.B00 | 9.1% | 9.4% | 13.6% | 2620 | 15.2 | ||
4239 | 2250 | 28482 | 28494 | 7 | |||||||
4239 | -2250 | 28500 | 28505 | 107 | |||||||
4239 | 2250 | 28506 | 28510 | dst28509_02.B00 | 29.5% | 22% | 36% | 75 | 18.1 | ||
5627 | 2250 | 27356 | 27364 | dst27358_02.B00 | 33.2% | 27.8% | 41.3% | 56 | 19.4 | 44.6 | 40.1 |
5627 | -2250 | 27366 | 27380 | dst27368_02.B00 | 12.6% | 14.8% | 19.5% | 130 | 13.6 | 25.3 | 8.8 |
5627 | 2250 | 27386 | 27499 | dst27388_02.B00 | 33.4% | 27.8% | 41.4% | 1210 | 20.2 | 44.8 | 40.1 |
5627 | 965 | 27502 | 27617 | 493 | |||||||
5735 | -2250 | 26874 | 27068 | dst26904_02.B00 | 13% | 15% | 20% | 1709 | 19.9 | 25.6 | 9.1 |
5735 | 2250 | 27069 | 27198 | dst27070_02.B00 | 33.3% | 28.8% | 42.2% | 1509 | 15 | 46 | 40.2 |
5764 | -2250 | 26468 | 26722 | dst26489_02.B00 | 12.2% | 14.4% | 19.1% | 1189 | 10 | 24.6 | 9.3 |
5764 | 0 | 26723 | 26775 | 268 | |||||||
5764 | -2250 | 26776 | 26851 | dst26779_02.B00 | 13.5% | 15.5% | 20.5% | 662 | 15.9 | 26.4 | 9.2 |
Cut on the number of photoelectrons
In this case is used a cut on the number of photoelectrons, which is
Used cuts and
Used file dst28181_03(energy 4.2GeV). In this case was applied cuts on the polar angle(
Tamuna: follow this link to see the OSIPENKO cuts described in part 5 add graphs of their effect below Dr. Forest I think I did this cuts but they do not change a lot. Maybe I am wrong.
Plot of vs
In this case is used file dst27070(Energy 5.735 GeV and Torus 2250) and are applied the following EC cuts: For ECtotal -
P<3
After using above cuts the number of entries decreases ~46%
0.5<P<1
The number of entries decreased by ~51.8%
1<P<1.5
The number of entries decreased approximately by 47.8%
1.5<P<2
In this case the number of entries decreased by 46.1%
2<P<2.5
In this case the number of entries decreased by 38%
P>3
Used file dst27070(Energy 5.735 GeV and Torus 2250) and are applied the following EC cuts: For ECtotal -
The number of entries decreased by~40.2%
Plot of EC_tot/P vs nphe for Electrons
Used file dst27070(Energy 5.735 GeV and Torus 2250)
p<3 GeV
The graphs below represents all electron candidates having a momentum smaller than 3 GeV. Negatively charged pions are the most likely particle to be misidentified as an electrons by the tracking software. A negatively charged pion having a momentum of 3 GeV would generate less than ?? photons in the cerenkov counter. As a result the electron candidates which
are thought to be misidentified pions. The images which follow represent the effects of several cuts made for the purpose of removing misidentified particles.p<3 GeV and
p<3 GeV, and
p<3 GeV, , and nphe>2.5
Dr. Forest , in this case I applied all cuts as you see.
Plot of EC_total vs EC_inner
In this case file dst28181_03.B00 was used(Energy 4.2 GeV and Torus +2250). The following cuts were applied:
, , ec_chi_sqr<0.1 and nphe>3.I wanted to compare this result with
http://www.jlab.org/Hall-B/secure/eg1/EG2000/sharon/ec_cut_4p2gev/Final_ec_cuts/Electron_cuts.html
Raster and vertex correction
A raster calibration and a cut on the vertex distribution was made in order to select electrons from the polarized target, also the ones scattered from other materials in the beam path. A plot of the uncorrected vertex distribution is presented below for dst27070_02.B00 file(energy=5.7GeV Torus=2250)
Pion
Summary Table
Tamuna: The pion id code is at:
http://www.jlab.org/Hall-B/secure/eg1/EG2000/josh/pion.cc
There are two subroutines, one which uses a constant cut for every paddle, one that has a different cut for every paddle. The only other requirement is that the particle be produced with an angle less than 48 degrees in the lab (so as to miss the magnet can). The requirment that the pion fail the electron cut is not written in stone. I still haven't checked to see the effects of it.
Beam Energy | Torus Current | Begin Run | End Run | file used | cuts | # trig( | )expected # evts( | )p>3, | , (%)p<3, | , (%)||
---|---|---|---|---|---|---|---|---|---|---|---|
and | |||||||||||
1606 | 1500 | 25488 | 25559 | dst25504_02.B00 | 60 | 3.2 | |||||
1606 | 1500 | 25669 | 25732 | dst25669_02.B00 | 226 | 10 | |||||
1606 | 1500 | 25742 | 26221 | dst25754_02.B00 | 3154 | 13.3 | |||||
1606 | -1500 | 26222 | 26359 | dst26224_02.B00 | 703 | 13.1 | |||||
1724 | -1500 | 27644 | 27798 | dst27649_02.B00 | 211 | 20 | |||||
2288 | 1500 | 27205 | 27351 | dst27225_02.B00 | 1647 | 16.1 | |||||
2562 | -1500 | 27799 | 27924 | dst27809_02.B00 | 1441 | 13.1 | |||||
2562 | -1500 | 27942 | 27995 | dst27942_02.B00 | 841 | 32.3 | |||||
2562 | 1500 | 28001 | 28069 | dst28002_02.B00 | 1013 | 30.7 | |||||
2792 | -1500 | 27936 | 27941 | dst27937_02.B00 | % | 69 | 20.6 | ||||
4239 | 2250 | 28074 | 28277 | dst28075_02.B00 | % | % | % | 2278 | 19.6 | ||
4239 | -2250 | 28280 | 28479 | dst28281_02.B00 | % | % | % | 2620 | 15.2 | ||
4239 | 2250 | 28506 | 28510 | dst28509_02.B00 | % | % | % | 75 | 18.1 | ||
5627 | 2250 | 27356 | 27364 | dst27358_02.B00 | % | % | % | 56 | 19.4 | 36.1 | 31.5 |
5627 | -2250 | 27366 | 27380 | dst27368_02.B00 | % | % | % | 130 | 13.6 | 25 | 43.8 |
5627 | 2250 | 27386 | 27499 | dst27388_02.B00 | % | % | % | 1210 | 20.2 | 39.8 | 32.4 |
5735 | -2250 | 26874 | 27068 | dst26904_02.B00 | % | % | % | 1709 | 19.9 | 22.5 | 46.4 |
5735 | 2250 | 27069 | 27198 | dst27070_02.B00 | % | % | % | 1509 | 15 | 34.6 | 32.9 |
5764 | -2250 | 26468 | 26722 | dst26489_02.B00 | % | % | % | 1189 | 10 | 25.2 | 44.3 |
5764 | -2250 | 26776 | 26851 | dst26779_02.B00 | % | % | % | 662 | 15.9 | 21.3 | 44 |
Table for Pions
I used the pion id code(both subroutines):
http://www.jlab.org/Hall-B/secure/eg1/EG2000/josh/pion.cc
Beam Energy | Torus Current | Begin Run | End Run | file used | cuts | # trig( | )expected # evts( | )||
---|---|---|---|---|---|---|---|---|---|
first(%) | second(%) | and | |||||||
1606 | 1500 | 25488 | 25559 | dst25504_02.B00 | 96.8 | 99 | 60 | 3.2 | |
1606 | 1500 | 25669 | 25732 | dst25669_02.B00 | 98.1 | 98.9 | 226 | 10 | |
1606 | 1500 | 25742 | 26221 | dst25754_02.B00 | 13.4 | 22.8 | 3154 | 13.3 | |
1606 | -1500 | 26222 | 26359 | dst26224_02.B00 | 11.3 | 15.3 | 703 | 13.1 | |
1724 | -1500 | 27644 | 27798 | dst27649_02.B00 | 15.3 | 18.7 | 211 | 20 | |
2288 | 1500 | 27205 | 27351 | dst27225_02.B00 | 16.4 | 18.9 | 1647 | 16.1 | |
2562 | -1500 | 27799 | 27924 | dst27809_02.B00 | 11.1 | 14.2 | 1441 | 13.1 | |
2562 | -1500 | 27942 | 27995 | dst27942_02.B00 | 11.1 | 14.2 | 841 | 32.3 | |
2562 | 1500 | 28001 | 28069 | dst28002_02.B00 | 22.4 | 23.1 | 1013 | 30.7 | |
2792 | -1500 | 27936 | 27941 | dst27937_02.B00 | 12.3 | 15.4 | % | 69 | 20.6 |
4239 | 2250 | 28074 | 28277 | dst28075_02.B00 | 16.7 | 14.3 | % | 2278 | 19.6 |
4239 | -2250 | 28280 | 28479 | dst28281_02.B00 | 10.4 | 12.6 | % | 2620 | 15.2 |
4239 | 2250 | 28506 | 28510 | dst28509_02.B00 | % | % | % | 75 | 18.1 |
5627 | 2250 | 27356 | 27364 | dst27358_02.B00 | 40.5 | 40.8 | % | 56 | 19.4 |
5627 | -2250 | 27366 | 27380 | dst27368_02.B00 | 9.7 | 12.7 | % | 130 | 13.6 |
5627 | 2250 | 27386 | 27499 | dst27388_02.B00 | 14.1 | 15.5 | % | 1210 | 20.2 |
5735 | -2250 | 26874 | 27068 | dst26904_02.B00 | 12.1 | 14.5 | % | 1709 | 19.9 |
5735 | 2250 | 27069 | 27198 | dst27070_02.B00 | 19.5 | 22.9 | % | 1509 | 15 |
5764 | -2250 | 26468 | 26722 | dst26489_02.B00 | 9.6 | 13.3 | % | 1189 | 10 |
5764 | -2250 | 26776 | 26851 | dst26779_02.B00 | 10.3 | 13.9 | % | 662 | 15.9 |
Plot of EC_tot/P vs nphe for Pions
Quality Checks
Run Summary Table
The table below uses a characteristic DST file to try and estimate the sample size for a semi-inclusive analysis of pion electroproduction. The column marked "cuts" below indicates the number of events kept when the standard EC based electron identification cuts, described above, are used:
. The next step will be to compare unpolarized pion production rates in order to evaluate the CLAS detectors efficiencies for measuring charged pions with different torus polarities. The question is whether you get the same rates for negatively charged pions in one torus polarity to positively charged pions using the opposite torus polarity.
Tamar: We need a convention for choosing only one of the pions in events with multiple pions. I believe I chose the pion with the highest momentum before.
Beam Energy | Torus Current | Target | Begin Run | End Run | file used | # trig( | )events remaining after | cuts(%)events remaining after | and cutsexpected # evts( | )
---|---|---|---|---|---|---|---|---|---|
4239 | 2250 | NH3 | 28205 | 28277 | /cache/mss/home/nguler/dst/dst28205_05.B00 | 1108.72 | 60.8 | 674.1 | |
ND3 | 28074 | 28190 | /cache/mss/home/nguler/dst/dst28187_05.B00 | 1117.87 | 59.6 | 666.25 | |||
-2250 | NH3 | 28407 | 28479 | /cache/mss/home/nguler/dst/dst28409_05.B00 | 1013.57 | 24.2 | 245.28 | ||
ND3 | 28278 | 28403 | /cache/mss/home/nguler/dst/dst28400_05.B00 | 1556.04 | 23.9 | 371.89 | |||
5735 | 2250 | NH3 | 27074 | 27195 | /cache/mss/home/nguler/dst/dst27095_05.B00 | 1442.25 | 57.7 | 832.18 | |
ND3 | 27116 | 27170 | /cache/mss/home/nguler/dst/dst27141_05.B00 | 624.55 | 59.1 | 369.10 | |||
-2250 | NH3 | 26911 | 27015 | /cache/mss/home/nguler/dst/dst26988.B00 | 900.93 | 80.7 | 727.05 | ||
ND3 | 27022 | 27068 | /cache/mss/home/nguler/dst/dst27055_05.B00 | 711.53 | 80 | 569.22 |
Rates
Unpolarized Pion electroproduction
Rates from other experiments in our Kinematic range
Pion Rates -vs- Paddle for opposite sign Torus fields
Tamar: Add a plot of X-bjorken -vs- paddle number below.
Dr. Forest: In X-bjorken do you mean. Used
file dst27070.
Q^2=4*2.5*Energy*sin(particle_ptr[i].trl1_theta/2)*sin(particle_ptr[i].trl1_theta/2);
X=Q/(2*(5.7-Energy)*mp);
![]()
Used file dst26988_05.B00(Energy=5.7GeV and Torus=-2250)
Used file dst26904_02.B00(energy=5.7 GeV and Torus=-2250). The graphs are for
Used file dst27070_02.B00(energy=5.7 GeV and Torus=2250).In that case they are for
Used file dst26904_02.B00(energy=5.7 GeV and Torus=-2250) for .