Analysis

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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[math]EC_{inner}[/math] and an outer[math]EC_{outer}[/math] region. The total energy absorbed by the calorimeter system is recorded in the variable [math]EC_{tot}[/math]. The momentum ([math]P[/math]) is calculated using the reconstructed track and the known torus magnetic field. The distributions of [math]EC_{tot}[/math] and [math]EC_{inner}[/math] are shown below where both have been divided by the electron momentum and no cuts have been applied.


[math]EC_{tot}\gt 0.2*p[/math]

Without any cuts we have 181018 entries. After using the following cut [math]EC_{tot}\gt 0.2*p[/math] we are getting 127719 entries, which is about 70.55% of 181018.

Etotal P using tot cut.gif Einner P using tot cut.gif

[math]EC_{inner}\gt 0.08*p[/math]

After the cut on the energy deposited into inner part of electron calorimeter, number of entries decreases by 22%.

Etotal P using inner cut.gif Einner P using inner cut.gif

Both cuts [math] EC_{tot}\gt 0.2*p [/math] and [math] EC_{inner}\gt 0.08*p [/math]

In case of using the cuts of the total deposited energy and the energy deposited into inner calorimeter number of entries decreases ~36%

Etotal P using both cuts.gif Einner P using both cuts.gif

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([math]10^6[/math]) expected # evts([math]10^6[/math]) p<3,[math]EC_{tot}\gt 0.2*p [/math],[math] EC_{inner}\gt 0.08*p[/math](%) p>3,[math]EC_{tot}\gt 0.24*p [/math],[math] EC_{inner}\gt 0.06*p[/math](%)
[math]EC_{tot}\gt 0.2*p[/math] [math]EC_{inner}\gt 0.08*p[/math] [math]EC_{tot}\gt 0.2*p [/math] and [math] EC_{inner}\gt 0.08*p[/math]
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 [math]nphe\gt 2.5[/math]. The plots below show the effect of the number of photoelectrons cuts on the Cerenkov distribution. We see that after using cut the number of entries decreases ~40.7%

Nphe before cut file 27070.gif Nphe1 after cut file 27070.gif


Used cuts [math]EC_{tot}\gt 0.24p[/math] and [math]EC_{inner}\gt 0.06p[/math]


Nphe before electron cuts file 27070.gif Nphe1 after electron cuts file 27070.gif


Used file dst28181_03(energy 4.2GeV). In this case was applied cuts on the polar angle([math]15\lt \theta\lt 20[/math]) and momentum([math]2.2\lt P\lt 2.6[/math]). Number of entries decreased by 96%(?????????????/)


Nphe before cuts file 28181.gif Nphe1 after cuts file 28181.gif

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 [math]EC_{tot}/p[/math] vs [math]EC_{inner}/p[/math]

In this case is used file dst27070(Energy 5.735 GeV and Torus 2250) and are applied the following EC cuts: For ECtotal - [math]EC_{tot}\gt 0.2p[/math], for EC inner - [math]EC_{inner}\gt 0.08p[/math].

P<3

After using above cuts the number of entries decreases ~46%

E total vs e inner1 before cuts file dst27070.gif E total vs e inner1 after cuts file dst27070.gif

0.5<P<1

The number of entries decreased by ~51.8%

E total vs e inner1 before cuts P1 file dst27070.gif E total vs e inner1 after cuts P1 file dst27070.gif

1<P<1.5

The number of entries decreased approximately by 47.8%

E total vs e inner1 before cuts P1.5 file dst27070.gif E total vs e inner1 after cuts P1.5 file dst27070.gif

1.5<P<2

In this case the number of entries decreased by 46.1%

E total vs e inner1 before cuts P2 file dst27070.gif E total vs e inner1 after cuts P2 file dst27070.gif

2<P<2.5

In this case the number of entries decreased by 38%

E total vs e inner1 before cuts P2.5 file dst27070.gif E total vs e inner1 after cuts P2.5 file dst27070.gif

P>3

Used file dst27070(Energy 5.735 GeV and Torus 2250) and are applied the following EC cuts: For ECtotal - [math]EC_{tot}\gt 0.24p[/math], for EC inner - [math]EC_{inner}\gt 0.06p[/math].

The number of entries decreased by~40.2%

E total vs e inner1 before cuts P3 file dst27070.gif E total vs e inner1 after cuts P3 file dst27070.gif

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 [math]n_{pe} \lt 1.xx [/math] are thought to be misidentified pions. The images which follow represent the effects of several cuts made for the purpose of removing misidentified particles.

E total vs nphe momentum cut file dst27070.gif

p<3 GeV and [math]EC_{inner}\gt 0.08p[/math]

E total P vs nphe momentum Ec inner cuts file dst27070.gif

p<3 GeV, [math]EC_{inner}\gt 0.08p[/math] and [math]EC_{tot}\gt 0.2p[/math]

E total P vs nphe momentum EC inner EC total cuts file dst27070.gif

p<3 GeV, [math]EC_{inner}\gt 0.08p[/math], [math]EC_{tot}\gt 0.2p[/math] and nphe>2.5
 Dr. Forest , in this case I applied all cuts as you see.

E total P vs nphe momentum EC inner EC total nphe cuts file dst27070.gif

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:[math]EC_{inner}\gt 0.005[/math], [math]EC_{tot}\gt 0.2*p[/math], 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

Etotal vs Einner file dst28181 03 before cuts.gif Etotal vs Einner file dst28181 03 after cuts.gif


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)

Vertex before corrections dst27070 file.gif

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([math]10^6[/math]) expected # evts([math]10^6[/math]) p>3,[math]EC_{tot}\lt 0.2*p [/math],[math] EC_{inner}\lt 0.08*p[/math](%) p<3,[math]EC_{tot}\lt 0.24*p [/math],[math] EC_{inner}\lt 0.06*p[/math](%)
[math]EC_{tot}\gt 0.2*p[/math] [math]EC_{inner}\gt 0.08*p[/math] [math]EC_{tot}\gt 0.2*p [/math] and [math] EC_{inner}\gt 0.08*p[/math]
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([math]10^6[/math]) expected # evts([math]10^6[/math])
first(%) second(%) [math]EC_{tot}\gt 0.2*p [/math] and [math] EC_{inner}\gt 0.08*p[/math]
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

E total vs nphe pions file dst27070.gif E total vs nphe electrons file dst27070.gif

Quality Checks

Run Summary Table

5764||-2250||26468||26722||dst26489_02.B00||12.2%||14.4%||19.1%||1189||10
Beam Energy Torus Current Begin Run End Run file used cuts # trig([math]10^6[/math]) expected # evts([math]10^6[/math])
[math]EC_{tot}\gt 0.2*p[/math] [math]EC_{inner}\gt 0.08*p[/math] [math]EC_{tot}\gt 0.2*p [/math] and [math] EC_{inner}\gt 0.08*p[/math]
4239 2250 28074 28277 dst28075_02.B00 35.3% 23.9% 40.5%
4239 -2250 28280 28479 dst28281_02.B00 9.1% 9.4% 13.6%
5627 2250 27356 27364 dst27358_02.B00 33.2% 27.8% 41.3% 56 19.4
5627 -2250 27366 27380 dst27368_02.B00 12.6% 14.8% 19.5% 130 13.6
5627 2250 27386 27499 dst27388_02.B00 33.4% 27.8% 41.4% 1210 20.2
5735 -2250 26874 27068 dst26904_02.B00 13% 15% 20% 1709 19.9
5735 2250 27069 27198 dst27070_02.B00 33.3% 28.8% 42.2% 1509 15
5764 -2250 26776 26851 dst26779_02.B00 13.5% 15.5% 20.5% 662 15.9

Rates

Unpolarized Pion electroproduction

Rates from other experiments in our Kinematic range

Pion Rates -vs- Paddle for opposite sign Torus fields

Tamar: we need to use a different runs. Run 26904 is a C12 target and 27070 is an empty target. You need to create a histogram for the FC variable and fill it outside the most inner loop (don't put it inside the loop over the number of particles).


Used file dst26904_02.B00(energy=5.7 GeV and Torus=-2250). The graphs are for [math]\pi^+[/math] .
Number of pions vs sc paddle file dst26904 .gif Sc paddle vs momentum file dst26904 .gif Momentum file dst26904 .gif

Used file dst27070_02.B00(energy=5.7 GeV and Torus=2250).In that case they are for [math]\pi^-[/math] .

Number of pions vs sc paddle file dst27070 .gif Sc paddle vs momentum file dst27070 .gif Momentum file dst27070 .gif


Used file dst26904_02.B00(energy=5.7 GeV and Torus=-2250) for [math]\pi^-[/math] .

Momentum file dst26904 particle id 5.gif

Asymmetries

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