Technical note for Gas Ring ImagiNg CHerenkov (GRINCH) detector for E12-06-112 Huan Yao ∗ The college of William and Mary (Dated: June 18, 2013) Background Use GRINCH for Bigbite in experiment E12-06-112 . Purpose Design GRINCH to extract the electrons from detected particles. Method Simulate GRINCH in Geant4 and build prototype detector to test it. Results FIXME. Conclusions FIXME. I. INTRODUCTION The E12-06-112 will measure the A n 1 asymmetry in the DIS region up to x Bj ≈ 0.71 through the reaction 3 He(e,e ′ ) using the Hall A polarized 3 He target and BigBite spectrometer with beam energies of E =6.6 and 8.8 GeV. The BigBite spectrometer will be fixed at a scattering angle of 30 ◦ . From previous experiments with 3-6 GeV beam energies, 12-15µA at the same angle and target, it is found that the background singles rates in the BigBite gas Cherenkov detector were unexpectedly high, particularly on the side of the detector closest to the beamline. Based on the studies done during those runs, the issues are associated with large diameter (5”) PMT’s. Those PMT’s require long ADC gate, have large cross sectional area of tube and thick glass PMT face. They are also very sensitive to magnetic fields, which ultimately limited the number of photoelectrons produced per event in the old BigBite Cherenkov detector. For E12-06-112 , the beam current will be increased to 30µA and a longer target (50cm active length) will be used, resuling in an increase in overall rates at the location of BigBite by a factor of approximately 4 or more. Clearly a new Cherenkov detector is required o handle this large background and overall rates. A new heavy Gas Ring-ImagiNg CHerenkov (GRINCH) detector that uses a single large array of small-diameter PMT’s and timing information to detect Cherenkov radiation in a high rate environment. The proposed GRINCH detect will use a segmented array of ∼ 553 29mm(Diameter) PMT’s located on the large- angle side of BigBite. Approximately 4 cylindrical mirrors will be used to transport the Cherenkov light to the PMT array. 1. The detector must fit within a 90 cm keep-out zone between the GEM chambers in the new BigBite(BB) detector frame. For the purpose of assembling GRINCH to BB frame, 2.5 cm gap at front and back side of GRINCH should be conserved. So the length of GRINCH ≤ 85 cm. 2. It was observed during the d n 2 experiment that the performance of the Cherenkov detector was significantly compromised by unexpectedly large background rates in the PMT. The multi-wire drift chambers(MWDCs) however, were measuring rates that were consistent with previous BigBite experiments and a Monte Carlo simulation 1 . Through shielding studies, many attempts were made to understand and eliminate the background. However, no significant drop in the background rate was achieved during the d2n run. Later, the simulation 2 showed that the neutron induced background rate in the 5” tubes was three orders of magnitude smaller than the total background rate measured during d2n. And the other simulation 1 have shown that a significant background of low-energy electrons is present due to production from material near the beam line and in the target scattering chamber which was not under vacuum. Bench tests 3 have shown that ∼ 1 MeV electrons from a 106 Ru source will produce Cherenkov radiation in the PMT glass which produces a single-photoelectron hit 30% of the time. Segmented PMT array (29mm tubes); Area=0.05x smaller than 5” tube; 3x thinner face. PMT array located at large angle side away from beam pipe. 3. C 4 F 8 O heavy gas radiator (n =1.00135 at 1 atm). 4. No ADC (240ns gate) during production runs.Search for timing clusters in 5-10 ns window and clusters of 10 PMT ′ s with threshold of 20-30% of the single p.e. ∗ E-mail me at:[email protected]
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Technical note for Gas Ring ImagiNg CHerenkov (GRINCH) detector for E12-06-112
Huan Yao∗
The college of William and Mary
(Dated: June 18, 2013)
Background Use GRINCH for Bigbite in experiment E12-06-112 .
Purpose Design GRINCH to extract the electrons from detected particles.
Method Simulate GRINCH in Geant4 and build prototype detector to test it.
Results FIXME.
Conclusions FIXME.
I. INTRODUCTION
The E12-06-112 will measure the An1asymmetry in the DIS region up to xBj ≈ 0.71 through the reaction 3 ~He(~e, e′)
using the Hall A polarized 3He target and BigBite spectrometer with beam energies of E = 6.6 and 8.8 GeV. TheBigBite spectrometer will be fixed at a scattering angle of 30◦. From previous experiments with 3-6 GeV beamenergies, 12-15µA at the same angle and target, it is found that the background singles rates in the BigBite gasCherenkov detector were unexpectedly high, particularly on the side of the detector closest to the beamline. Basedon the studies done during those runs, the issues are associated with large diameter (5”) PMT’s. Those PMT’srequire long ADC gate, have large cross sectional area of tube and thick glass PMT face. They are also very sensitiveto magnetic fields, which ultimately limited the number of photoelectrons produced per event in the old BigBiteCherenkov detector.For E12-06-112 , the beam current will be increased to 30µA and a longer target (50cm active length) will be used,
resuling in an increase in overall rates at the location of BigBite by a factor of approximately 4 or more. Clearly a newCherenkov detector is required o handle this large background and overall rates. A new heavy Gas Ring-ImagiNgCHerenkov (GRINCH) detector that uses a single large array of small-diameter PMT’s and timing information todetect Cherenkov radiation in a high rate environment.The proposed GRINCH detect will use a segmented array of ∼ 553 29mm(Diameter) PMT’s located on the large-
angle side of BigBite. Approximately 4 cylindrical mirrors will be used to transport the Cherenkov light to the PMTarray.
1. The detector must fit within a 90 cm keep-out zone between the GEM chambers in the new BigBite(BB) detectorframe. For the purpose of assembling GRINCH to BB frame, 2.5 cm gap at front and back side of GRINCHshould be conserved. So the length of GRINCH ≤ 85 cm.
2. It was observed during the dn2experiment that the performance of the Cherenkov detector was significantly
compromised by unexpectedly large background rates in the PMT. The multi-wire drift chambers(MWDCs)however, were measuring rates that were consistent with previous BigBite experiments and a Monte Carlosimulation1. Through shielding studies, many attempts were made to understand and eliminate the background.However, no significant drop in the background rate was achieved during the d2n run. Later, the simulation2
showed that the neutron induced background rate in the 5” tubes was three orders of magnitude smaller than the
total background rate measured during d2n. And the other simulation1 have shown that a significant backgroundof low-energy electrons is present due to production from material near the beam line and in the target scatteringchamber which was not under vacuum. Bench tests3 have shown that ∼ 1 MeV electrons from a 106Ru sourcewill produce Cherenkov radiation in the PMT glass which produces a single-photoelectron hit 30% of the time.Segmented PMT array (29mm tubes); Area=0.05x smaller than 5” tube; 3x thinner face. PMT array locatedat large angle side away from beam pipe.
3. C4F8O heavy gas radiator (n = 1.00135 at 1 atm).
4. No ADC (240ns gate) during production runs.Search for timing clusters in 5-10 ns window and clusters of 10PMT′s with threshold of 20-30% of the single p.e.
∗E-mail me at:[email protected]
2
5. Long active path length to have more photons.
6. ηe ≈ 1 and ηπ ≤ 0.1
7. Add magnetic shielding for PMT array.
1. Scattering electron energy from 1.6 GeV to 3.3 GeV.
2. 30◦scattering angle.
3. 70cm active path length.
4. 29mm PMT (9125B) typical spectral response wavelength is from 275nm to 635nm. Positive HV (≤ 1500V ).
5. C4F8O heavy gas radiator (n = 1.00135 at 1 atm, n = 1.002 at 1.5 atm).
6. Assume 110cm path length for photon, radius of ring on PMT array is 7cm. Approximately 9-10 PMT’s in acluster with single p.e. hit.
7. PMT array located at large angle side away from beam pipe.
8. Expect 5-10 times increase in luminosity over previous BigBite experiments.
9. No ADC (240ns gate) during production runs.
Particle P threshold (MeV/c) θ (◦) Number of γ
e− 8 3.64 36
π 2196 3.28 29
TABLE I: Cherenkov light table for e− and π. Number of photons is calculated with PMT quantum effiency, mirrorreflective effiency and effective PMT area. The gas path length is 70cm. λ ranges from 275nm to 635nm. n = 1.002
for C4F8O at 1.5 atm.
II. FEATURES OF GAS CHERENKOV DETECTOR
Gas Cherenkov detector is used for particle identification in E12-06-112 . When a charged particle with speedv = βc travels through a transparent material with index of refraction n, if v is greater than the speed of light in thematerial c
n(c is the speed of light in the vacuum), the particle will generate Cherenkov light. This is because the
particle along the trajectory in the material at each point radiates, if v ≥ cn, the interference of each point will be
maximum at an angle θc and disappear at other directions. By detecting if a given particle emits Cherenkov light,one can detect if its velocity is larger than a threshold velocity dependent on the material as shown in equation 1.The angle θc of Cherenkov light is equation 2.
β ≥1
n
p ≥mc√n2 − 1
(1)
cosθc =1
βn(2)
The number of photons emitted along the particle path for a particle with charge ze and per unit energy intervalof the photons is
d2N
dEdx=
αz2
h̄csin2θc ≈ 370sin2θc(E)eV −1cm−1 (z = 1) (3)
E =2πh̄c
λ=
1240(eV )
λ(nm)
d2N
dλdx=
2παz2
λ2
(
1−1
β2n2(λ)
)
(4)
3
FIG. 1: Side view of BigBite
III. DESIGN
The coordinate system used here is the following:
• X-axis(Vertical down or height H): Gas Cherenkov center to bottom
• Y-axis(Horizontal left or length L): Gas Cherenkov center to left side
• Z-axis(Beam or thickness or width W): Gas Cherenkov center to back side
• Box
– Entrance and exit window dimension are 50cm(L) X 200cm(H) X 0.635cm(T)
– Mirror dimension is 130cm(Radius) X 60cm(L) X 70cm(H) X (0.635cm(T). The distance between thecentral point of surface and the central point of two edge points is around 4.8cm. The central point ofsurface is located at (x,0,28.7cm) relative to the central of box. Here x means different vertical offset foreach mirror. Once it’s located at the point, all mirrors need to be rotated -17.92◦about X-axis with respectto the central point of the surface. Then rotate ∓16◦about horizontal axis through central point of thesurface w.r.t the same point for top and bottom mirrors respectively.
IV. GEANT4 SIMULATION
The coordinate system used here is the following:
• X-axis(Beam or depth L): Bigbite center to gas Cherenkov center
• Y-axis(Vertical up or height H): gas Cherenkov center to top
• Z-axis(Beam right or width W): gas Cherenkov center to right side
4
PRODUCED BY AN AUTODESK EDUCATIONAL PRODUCT
PRODUCED BY AN AUTODESK EDUCATIONAL PRODUCT
PR
OD
UC
ED
BY
AN
AU
TO
DE
SK
ED
UC
AT
ION
AL P
RO
DU
CT
PR
OD
UC
ED
BY
AN
AU
TO
DE
SK
ED
UC
AT
ION
AL P
RO
DU
CT
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
hyao 6/18/2013
DWG NO
A1n_SideView
TITLE
A1n
SIZE
CSCALE
REV
1:12
Material
Mass 9111.7 kg
89.0
45.9
81.2
111.4
28.5
70.0̇
65.0
187.5
10.0̇
91.0
97.0
4.0
122.5
85.0
219.0
228.0
240.0
258.0
4.010.0
34.0
150.0
192.0
200.0
210.0
221.0
FIG. 2: Side view of A1n simulation (unit: cm)
PRODUCED BY AN AUTODESK EDUCATIONAL PRODUCT
PRODUCED BY AN AUTODESK EDUCATIONAL PRODUCT
PR
OD
UC
ED
BY
AN
AU
TO
DE
SK
ED
UC
AT
ION
AL P
RO
DU
CT
PR
OD
UC
ED
BY
AN
AU
TO
DE
SK
ED
UC
AT
ION
AL P
RO
DU
CT
1
1
2
2
3
3
4
4
A A
B B
C C
D D
SHEET 1 OF 1
DRAWN
CHECKED
QA
MFG
APPROVED
hyao 6/18/2013
DWG NO
A1n_TopView
TITLE
A1n
SIZE
CSCALE
REV
1:12
Material
Mass 9111.7 kg
60.0
30.0̇
263.7
10.8
FIG. 3: Top view of A1n simulatio (unit: cm). The angular acceptance of BigBite is ≈ ±2.5◦.
Design goals are:
• Mirror array to cover the acceptance of scattered particles.
• PMT array to get as more photon-electrons per PMT as possible but enough number of PMTs to be a ring.
5
(a) Top view of gas Cherenkov detector.
(b) Side view of gas Cherenkov detector.
FIG. 4: Gas Cherenkov detector GEANT4 simulation
The definitions in the figures:
• Mirror array collection efficiency: Nλ hit on mirror
Nλ generated in GRINCH before mirror
• PMT array collection efficiency: Nλ hit on PMT
Nλ reflected from mirror
The following are some studies of design parameters:
• L is the distance from Bigbite magnet center to the center of gas Cherenkov detector. The larger the distanceis, the smaller the angular acceptance of GRINCH is if the geometry of GRINCH is fixed. But we also wantto have a gap between GRINCH and other neighbouring detectors in the package so that we have to keep thedistance far enough to fit the GRINCH in.
6
Distance from BB to GC(cm)100 120 140 160 180 200
Mirr
or c
olle
ctio
n ef
f
0.85
0.9
0.95
1
1.05
Mirror collection eff vs Distance from BB to GC(cm) Mirror collection eff vs Distance from BB to GC(cm)
Entries 10Mean x 145Mean y 0.958RMS x 28.72RMS y 0.009316
Mirror collection eff vs Distance from BB to GC(cm)
(a) Mirror array collection efficiency vs L (cm).
Distance from BB to GC(cm)100 120 140 160 180 200
PM
T c
olle
ctio
n ef
f
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs Distance from BB to GC(cm) PMT collection eff vs Distance from BB to GC(cm)
Entries 10Mean x 145Mean y 0.705RMS x 28.72RMS y 0.004588
PMT collection eff vs Distance from BB to GC(cm)
(b) PMT array collection efficiency vs L (cm).
Distance from BB to GC(cm)100 120 140 160 180 200
pmt
N
9.6
9.810
10.210.410.610.8
1111.211.411.611.8
vs Distance from BB to GC(cm)pmtN vs Distance from BB to GC(cm)pmtN
Entries 10Mean x 145Mean y 10.67RMS x 28.72RMS y 0.05884
vs Distance from BB to GC(cm)pmtN
(c) NPMT vs L (cm).
Distance from BB to GC(cm)100 120 140 160 180 200
pmt
/Np.
eN
2.3
2.4
2.5
2.6
2.7
vs Distance from BB to GC(cm)pmt/Np.eN vs Distance from BB to GC(cm)pmt
/Np.eN
Entries 10Mean x 145Mean y 2.481RMS x 28.72RMS y 0.01974
vs Distance from BB to GC(cm)pmt/Np.eN
(d) Np.e/NPMT vs L.
FIG. 5: Study of L (cm) between Bigbite magnet center and gas Cherenkov detector center.
The distance L in design is 165 ± 3 cm. This will make sure there will be around 20 cm gap between gasCherenkov detector and the front 2nd GEM detector and the back MWDC detector.
• The active length La of gas decides how long the electron is passing through the gas. The longer the length is,the more cherenkov light is generated. Then finally more photon-electrons are detected by PMT array.
7
Gas active length(cm)40 50 60 70 80
Mirr
or c
olle
ctio
n ef
f
0.8
0.85
0.9
0.95
1
1.05
Mirror collection eff vs Gas active length(cm) Mirror collection eff vs Gas active length(cm)
Entries 10Mean x 57.5Mean y 0.9216RMS x 14.36RMS y 0.03327
Mirror collection eff vs Gas active length(cm)
(a) Mirror array collection efficiency vs La (cm).
Gas active length(cm)40 50 60 70 80
PM
T c
olle
ctio
n ef
f
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs Gas active length(cm) PMT collection eff vs Gas active length(cm)
Entries 10Mean x 57.5Mean y 0.7051RMS x 14.36RMS y 0.004048
PMT collection eff vs Gas active length(cm)
(b) PMT array collection efficiency vs La (cm).
Gas active length(cm)40 50 60 70 80
pmt
N
7
8
9
10
11
12
vs Gas active length(cm)pmtN vs Gas active length(cm)pmtN
Entries 10Mean x 57.5Mean y 9.112RMS x 14.36RMS y 1.498
vs Gas active length(cm)pmtN
(c) NPMT vs La (cm).
Gas active length(cm)40 50 60 70 80
pmt
/Np.
eN
1.8
2
2.2
2.4
2.6
2.8
vs Gas active length(cm)pmt/Np.eN vs Gas active length(cm)pmt
/Np.eN
Entries 10Mean x 57.5Mean y 2.327RMS x 14.36RMS y 0.2148
vs Gas active length(cm)pmt/Np.eN
(d) Np.e/NPMT vs La (cm).
FIG. 6: Study of La (cm) active length of gas between GRINCH front surface and mirror surface center.
8
cutpeN10 15 20 25 30
e- d
etec
tion
effic
ienc
y
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
cutpe
e- detection efficiency vs N cutpe
e- detection efficiency vs N
(a) e- for La = 70 cm
P (MeV)1600 1800 2000 2200 2400 2600 2800 3000 3200
- re
ject
ion
π
-310
-210
-110
1
cutpe
- rejection vs P (MeV) for different Nπ
=8peN=11peN=14peN=17peN=20peN=23peN=26peN=29peN=32peN
cutpe
- rejection vs P (MeV) for different Nπ
(b) π− for La = 70 cm
cutpeN10 15 20 25 30
e- d
etec
tion
effic
ienc
y
0
0.2
0.4
0.6
0.8
1
cutpe
e- detection efficiency vs N cutpe
e- detection efficiency vs N
(c) e- for La = 60 cm
P (MeV)1600 1800 2000 2200 2400 2600 2800 3000 3200
- re
ject
ion
π
-310
-210
-110
1
cutpe
- rejection vs P (MeV) for different Nπ
=8peN=11peN=14peN=17peN=20peN=23peN=26peN=29peN=32peN
cutpe
- rejection vs P (MeV) for different Nπ
(d) π− for La = 60 cm
cutpeN10 15 20 25 30
e- d
etec
tion
effic
ienc
y
0
0.2
0.4
0.6
0.8
1
cutpe
e- detection efficiency vs N cutpe
e- detection efficiency vs N
(e) e- for La = 45 cm
P (MeV)1600 1800 2000 2200 2400 2600 2800 3000 3200
- re
ject
ion
π
-310
-210
-110
1
cutpe
- rejection vs P (MeV) for different Nπ
=8peN=11peN=14peN=17peN=20peN=23peN=26peN=29peN=32peN
cutpe
- rejection vs P (MeV) for different Nπ
(f) π− for La = 45 cm
FIG. 7: e− detection efficiency / π− rejection vs La (cm). The error is statistical error.
9
• The larger the gas pressure is, the more atoms of gas exist, the more cherenkov light is generated.
Gas Pressure(atm)0 0.5 1 1.5 2 2.5
Mirr
or c
olle
ctio
n ef
f
0
0.2
0.4
0.6
0.8
1
Mirror collection eff vs Gas Pressure(atm) Mirror collection eff vs Gas Pressure(atm)
Entries 10Mean x 1.35Mean y 0.8634RMS x 0.8617RMS y 0.2879
Mirror collection eff vs Gas Pressure(atm)
(a) Mirror array collection efficiency vs Pressure (atm).
Gas Pressure(atm)0 0.5 1 1.5 2 2.5
PM
T c
olle
ctio
n ef
f
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
PMT collection eff vs Gas Pressure(atm) PMT collection eff vs Gas Pressure(atm)
Entries 10Mean x 1.35Mean y 0.6389RMS x 0.8617RMS y 0.213
PMT collection eff vs Gas Pressure(atm)
(b) PMT array collection efficiency vs Pressure (atm).
Gas Pressure(atm)0 0.5 1 1.5 2 2.5
pmt
N
0
2
4
6
8
10
12
14
16
18
vs Gas Pressure(atm)pmtN vs Gas Pressure(atm)pmtN
Entries 10Mean x 1.35Mean y 9.376RMS x 0.8617RMS y 5.274
vs Gas Pressure(atm)pmtN
(c) NPMT vs Pressure (atm).
Gas Pressure(atm)0 0.5 1 1.5 2 2.5
pmt
/Np.
eN
0
0.5
1
1.5
2
2.5
3
vs Gas Pressure(atm)pmt/Np.eN vs Gas Pressure(atm)pmt
/Np.eN
Entries 10Mean x 1.35Mean y 2.151RMS x 0.8617RMS y 0.7724
vs Gas Pressure(atm)pmt/Np.eN
(d) Np.e/NPMT vs Pressure (atm).
FIG. 8: Study of gas pressure (atm).
10
cutpeN5 10 15 20 25 30
e-η
0.2
0.4
0.6
0.8
1
cutpe
) vs Ne-
ηe- detection efficiency ( cutpe
) vs Ne-
ηe- detection efficiency (
(a) e− detect efficiency for P = 1.0atm
cutpeN5 10 15 20 25 30
-πη
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
cutpe
) vs N-πη- efficiency (π cut
pe) vs N
-πη- efficiency (π
(b) π− efficiency for P = 1.0atm
cutpeN4 6 8 10 12 14 16 18
e-η
0.8
0.85
0.9
0.95
1
cut (Zoom)pe
) vs Ne-
ηe- detection efficiency ( cut (Zoom)pe
) vs Ne-
ηe- detection efficiency (
(c) e− detect efficiency for P = 1.0atm (Zoom)
cutpeN4 6 8 10 12 14 16 18
-πη
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
cut (Zoom)pe
) vs N-πη- efficiency (π cut (Zoom)
pe) vs N
-πη- efficiency (π
(d) π− efficiency for P = 1.0atm (Zoom)
cutpeN10 15 20 25 30
e- d
etec
tion
effic
ienc
y
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
cutpe
e- detection efficiency vs N cutpe
e- detection efficiency vs N
(e) e− detect efficiency for P = 1.5atm
cutpeN10 15 20 25 30
- co
ntam
inat
ion
π
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
cutpe- contamination vs Nπ cutpe- contamination vs Nπ
(f) π− efficiency for P = 1.5atm
cutpeN8 10 12 14 16 18 20
e- d
etec
tion
effic
ienc
y
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
/ ndf 2χ 0.01536 / 3Prob 0.9995p0 2.103± -7.572 p1 0.1081± 0.2788
/ ndf 2χ 0.01536 / 3Prob 0.9995p0 2.103± -7.572 p1 0.1081± 0.2788
cut (Zoom)pe
e- detection efficiency vs N
cutpeN8 10 12 14 16 18 20
- co
ntam
inat
ion
π
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
/ ndf 2χ 399.9 / 3Prob 0p0 0.01745± 0.67 p1 0.001433± -0.1821
/ ndf 2χ 399.9 / 3Prob 0p0 0.01745± 0.67 p1 0.001433± -0.1821
cut (Zoom)pe- contamination vs Nπ
11
• Since the PMTs are sensitive to magnetic field from target and Bigbite magnet, we need to install shieldingaround PMT array. This will add a gap between the front edge of PMT box and the front surface of PMTarray. The larger the gap is, the smaller the effect of magnetic field to the PMTs is. But if it is too large, it willincrease the size and the weight of gas Cherenkov detector.
Gap between box and front surface of PMT(cm)2 4 6 8 10 12 14 16 18 20
Mirr
or c
olle
ctio
n ef
f
0.85
0.9
0.95
1
1.05
Mirror collection eff vs Gap between box and front surface of PMT(cm) Mirror collection eff vs Gap between box and front surface of PMT(cm)
Entries 10Mean x 10Mean y 0.9524RMS x 5.745RMS y 0.004976
Mirror collection eff vs Gap between box and front surface of PMT(cm)
(a) Mirror array collection efficiency vs Gap (cm).
Gap between box and front surface of PMT(cm)2 4 6 8 10 12 14 16 18 20
PM
T c
olle
ctio
n ef
f
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs Gap between box and front surface of PMT(cm) PMT collection eff vs Gap between box and front surface of PMT(cm)
Entries 10Mean x 10Mean y 0.7097RMS x 5.745RMS y 0.001894
PMT collection eff vs Gap between box and front surface of PMT(cm)
(b) PMT array collection efficiency vs Gap (cm).
Gap between box and front surface of PMT(cm)2 4 6 8 10 12 14 16 18 20
pmt
N
9.5
10
10.5
11
11.5
vs Gap between box and front surface of PMT(cm)pmtN vs Gap between box and front surface of PMT(cm)pmt
N
Entries 10Mean x 10Mean y 10.72RMS x 5.745RMS y 0.1117
vs Gap between box and front surface of PMT(cm)pmtN
(c) NPMT vs Gap (cm).
Gap between box and front surface of PMT(cm)2 4 6 8 10 12 14 16 18 20
pmt
/Np.
eN
2.2
2.3
2.4
2.5
2.6
2.7
vs Gap between box and front surface of PMT(cm)pmt/Np.eN vs Gap between box and front surface of PMT(cm)pmt
/Np.eN
Entries 10Mean x 10Mean y 2.444RMS x 5.745RMS y 0.01228
vs Gap between box and front surface of PMT(cm)pmt/Np.eN
(d) Np.e/NPMT vs Gap (cm).
FIG. 10: Study of Gap (cm) between PMT box front edge and PMT array front surface.
• The rotation angle θ of PMT box is the angle about Y-axis. If it is too small, the PMT box will block theentrance of GRINCH. If it is too large, the width of GRINCH will be increased if we keep the distance betweenmirror surface center and PMT surface fixed.
12
PMT box rotation angle(deg)40 50 60 70 80
Mirr
or c
olle
ctio
n ef
f
0.85
0.9
0.95
1
1.05
Mirror collection eff vs PMT box rotation angle(deg) Mirror collection eff vs PMT box rotation angle(deg)
Entries 10Mean x 57.5Mean y 0.9474RMS x 14.36RMS y 0.0141
Mirror collection eff vs PMT box rotation angle(deg)
(a) Mirror array collection efficiency vs PMT Box θ (deg).
PMT box rotation angle(deg)40 50 60 70 80
PM
T c
olle
ctio
n ef
f
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs PMT box rotation angle(deg) PMT collection eff vs PMT box rotation angle(deg)
Entries 10Mean x 57.5Mean y 0.7063RMS x 14.36RMS y 0.004514
PMT collection eff vs PMT box rotation angle(deg)
(b) PMT array collection efficiency vs PMT Box θ (deg).
PMT box rotation angle(deg)40 50 60 70 80
pmt
N
9.5
10
10.5
11
11.5
12
12.5
vs PMT box rotation angle(deg)pmtN vs PMT box rotation angle(deg)pmtN
Entries 10Mean x 57.5Mean y 10.76RMS x 14.36RMS y 0.3257
vs PMT box rotation angle(deg)pmtN
(c) NPMT vs PMT Box θ (deg).
PMT box rotation angle(deg)40 50 60 70 80
pmt
/Np.
eN
2.2
2.3
2.4
2.5
2.6
2.7
vs PMT box rotation angle(deg)pmt/Np.eN vs PMT box rotation angle(deg)pmt
/Np.eN
Entries 10Mean x 57.5Mean y 2.472RMS x 14.36RMS y 0.02257
vs PMT box rotation angle(deg)pmt/Np.eN
(d) Np.e/NPMT vs PMT Box θ (deg).
FIG. 11: Study of PMT Box angle θ (deg) about vertical-axis.
• The focal length of mirror is about half of mirror radius. And here I set the focal length is equal to the distancebetween mirror surface center and PMT array surface. The smaller the length is, the smaller the size of ring is,then the smaller the number of fired PMTs is.
13
Distance from mirror center to front surface of PMT (cm)40 50 60 70 80
Mirr
or c
olle
ctio
n ef
f
0.7
0.75
0.8
0.85
0.9
0.95
1
1.05
Mirror collection eff vs Distance from mirror center to front surface of PMT (cm) Mirror collection eff vs Distance from mirror center to front surface of PMT (cm)
Entries 10Mean x 57.5Mean y 0.9173RMS x 14.36RMS y 0.05834
Mirror collection eff vs Distance from mirror center to front surface of PMT (cm)
(a) Mirror array collection efficiency vs LF (cm).
Distance from mirror center to front surface of PMT (cm)40 50 60 70 80
PM
T c
olle
ctio
n ef
f
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs Distance from mirror center to front surface of PMT (cm) PMT collection eff vs Distance from mirror center to front surface of PMT (cm)
Entries 10Mean x 57.5Mean y 0.7049RMS x 14.36RMS y 0.005186
PMT collection eff vs Distance from mirror center to front surface of PMT (cm)
(b) PMT array collection efficiency vs LF (cm).
Distance from mirror center to front surface of PMT (cm)40 50 60 70 80
pmt
N
7
8
9
10
11
12
vs Distance from mirror center to front surface of PMT (cm)pmtN vs Distance from mirror center to front surface of PMT (cm)pmtN
Entries 10Mean x 57.5Mean y 10.05RMS x 14.36RMS y 1.19
vs Distance from mirror center to front surface of PMT (cm)pmtN
(c) NPMT vs LF (cm).
Distance from mirror center to front surface of PMT (cm)40 50 60 70 80
pmt
/Np.
eN
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3
vs Distance from mirror center to front surface of PMT (cm)pmt
/Np.eN vs Distance from mirror center to front surface of PMT (cm)pmt
/Np.eN
Entries 10Mean x 57.5Mean y 2.508RMS x 14.36RMS y 0.1406
vs Distance from mirror center to front surface of PMT (cm)pmt
/Np.eN
(d) Np.e/NPMT vs LF (cm).
FIG. 12: Study of LF (cm) focal length between mirror surface center and PMT array surface.
• Many rows of PMT array mean it will cover more reflected photons from mirror but at same time increase theheight and weight of PMT array and box.
14
Number of rows of PMT array40 50 60 70 80
Mirr
or c
olle
ctio
n ef
f
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
1.02
1.04
Mirror collection eff vs Number of rows of PMT array Mirror collection eff vs Number of rows of PMT array
Entries 10Mean x 57.5Mean y 0.9529RMS x 14.36RMS y 0.004807
Mirror collection eff vs Number of rows of PMT array
(a) Mirror array collection efficiency vs Nrow.
Number of rows of PMT array40 50 60 70 80
PM
T c
olle
ctio
n ef
f
0.5
0.55
0.6
0.65
0.7
0.75
PMT collection eff vs Number of rows of PMT array PMT collection eff vs Number of rows of PMT array
Entries 10Mean x 57.5Mean y 0.6735RMS x 14.36RMS y 0.05858
PMT collection eff vs Number of rows of PMT array
(b) PMT array collection efficiency vs Nrow.
Number of rows of PMT array40 50 60 70 80
pmt
N
8
8.5
9
9.5
10
10.5
11
11.5
vs Number of rows of PMT arraypmtN vs Number of rows of PMT arraypmtN
Entries 10Mean x 57.5Mean y 10.22RMS x 14.36RMS y 0.7607
vs Number of rows of PMT arraypmtN
(c) NPMT vs Nrow.
Number of rows of PMT array40 50 60 70 80
pmt
/Np.
eN
2.2
2.3
2.4
2.5
2.6
2.7
vs Number of rows of PMT arraypmt/Np.eN vs Number of rows of PMT arraypmt/Np.eN
Entries 10Mean x 57.5Mean y 2.442RMS x 14.36RMS y 0.03401
vs Number of rows of PMT arraypmt/Np.eN
(d) Np.e/NPMT vs Nrow.
FIG. 13: Study of Nrow of PMT array.
• In the simulation, the PMT array is organized as Nmin + 1, Nmin, Nmin + 1... So to make sure the PMT arraycover the reflected photon area and get enough NPMT , we need enough Nmin but not too many otherwise itwill increase the width and weight of PMT array and box.
15
Min number of PMTs in a row2 4 6 8 10 12
Mirr
or c
olle
ctio
n ef
f
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
1.02
1.04
Mirror collection eff vs Min number of PMTs in a row Mirror collection eff vs Min number of PMTs in a row
Entries 10Mean x 6.5Mean y 0.9544RMS x 2.872RMS y 0.004314
Mirror collection eff vs Min number of PMTs in a row
(a) Mirror array collection efficiency vs Min NPMT in a row.
Min number of PMTs in a row2 4 6 8 10 12
PM
T c
olle
ctio
n ef
f
0.5
0.55
0.6
0.65
0.7
0.75
PMT collection eff vs Min number of PMTs in a row PMT collection eff vs Min number of PMTs in a row
Entries 10Mean x 6.5Mean y 0.6816RMS x 2.872RMS y 0.05245
PMT collection eff vs Min number of PMTs in a row
(b) PMT array collection efficiency vs Min NPMT in a row.
Min number of PMTs in a row2 4 6 8 10 12
pmt
N
7.5
8
8.5
9
9.5
10
10.5
11
11.5
vs Min number of PMTs in a rowpmtN vs Min number of PMTs in a rowpmtN
Entries 10Mean x 6.5Mean y 10.25RMS x 2.872RMS y 0.8151
vs Min number of PMTs in a rowpmtN
(c) NPMT vs Min NPMT in a row.
Min number of PMTs in a row2 4 6 8 10 12
pmt
/Np.
eN
2.2
2.3
2.4
2.5
2.6
2.7
vs Min number of PMTs in a rowpmt/Np.eN vs Min number of PMTs in a rowpmt
/Np.eN
Entries 10Mean x 6.5Mean y 2.463RMS x 2.872RMS y 0.02253
vs Min number of PMTs in a rowpmt/Np.eN
(d) Np.e/NPMT vs Min NPMT in a row.
FIG. 14: Study of minimum NPMT in a row.
• To converge more photons on the PMTs, we use hexagonal cone which is assumed to have 80% reflectivity insimulation as shown in Figure 15.
There are three important parameters for the cone:
– The maximum tangent radius is defined as the smallest distance between center and edge not edge pointat large side or the entrance of the cone. If this radius is too large, it will increase the distance betweeneach PMT and decrease the reflection efficiency so that the size and weight of PMT box and array will beincreased and the Np.e/NPMT will be decreased.
16
FIG. 15: Cone front view
GC PMT Cone max tangent radius(cm)1.2 1.4 1.6 1.8 2 2.2
Mirr
or c
olle
ctio
n ef
f
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
1.02
1.04
1.06
Mirror collection eff vs GC PMT Cone max tangent radius(cm) Mirror collection eff vs GC PMT Cone max tangent radius(cm)
Entries 10Mean x 1.7Mean y 0.9586RMS x 0.2872RMS y 0.00995
Mirror collection eff vs GC PMT Cone max tangent radius(cm)
(a) Mirror array collection efficiency vs PMT Cone max innertangent radius (cm).
GC PMT Cone max tangent radius(cm)1.2 1.4 1.6 1.8 2 2.2
PM
T c
olle
ctio
n ef
f
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
PMT collection eff vs GC PMT Cone max tangent radius(cm) PMT collection eff vs GC PMT Cone max tangent radius(cm)
Entries 10Mean x 1.7Mean y 0.6386RMS x 0.2872RMS y 0.1049
PMT collection eff vs GC PMT Cone max tangent radius(cm)
(b) PMT array collection efficiency vs PMT Cone max innertangent radius (cm).
GC PMT Cone max tangent radius(cm)1.2 1.4 1.6 1.8 2 2.2
pmt
N
6
7
8
9
10
11
12
13
14
vs GC PMT Cone max tangent radius(cm)pmtN vs GC PMT Cone max tangent radius(cm)pmtN
Entries 10Mean x 1.7Mean y 10.39RMS x 0.2872RMS y 2.08
vs GC PMT Cone max tangent radius(cm)pmtN
(c) NPMT vs PMT Cone max inner tangent radius (cm).
GC PMT Cone max tangent radius(cm)1.2 1.4 1.6 1.8 2 2.2
pmt
/Np.
eN
1.9
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
vs GC PMT Cone max tangent radius(cm)pmt/Np.eN vs GC PMT Cone max tangent radius(cm)pmt
/Np.eN
Entries 10Mean x 1.7Mean y 2.303RMS x 0.2872RMS y 0.1547
vs GC PMT Cone max tangent radius(cm)pmt/Np.eN
(d) Np.e/NPMT vs PMT Cone max inner tangent radius(cm).
FIG. 16: Study of PMT Cone max inner tangent radius (cm).
17
– The minimum tangent radius is defined as the smallest distance between center and edge at small sideor the exit of the cone. If this is too small, it will increase the slope of the cone causing the decreasingof reflection efficiency. If too large, not all the photons are hit on the active area of PMT on which thephotons are considered to be detected in simulation.
GC PMT Cone min tangent radius(cm)0.8 1 1.2 1.4 1.6 1.8
Mirr
or c
olle
ctio
n ef
f
0.860.880.9
0.920.940.960.98
11.021.04
1.061.08
Mirror collection eff vs GC PMT Cone min tangent radius(cm) Mirror collection eff vs GC PMT Cone min tangent radius(cm)
Entries 10Mean x 1.3Mean y 0.9591RMS x 0.2872RMS y 0.01241
Mirror collection eff vs GC PMT Cone min tangent radius(cm)
(a) Mirror array collection efficiency vs PMT Cone min innertangent radius (cm).
GC PMT Cone min tangent radius(cm)0.8 1 1.2 1.4 1.6 1.8
PM
T c
olle
ctio
n ef
f
0.3
0.4
0.5
0.6
0.7
PMT collection eff vs GC PMT Cone min tangent radius(cm) PMT collection eff vs GC PMT Cone min tangent radius(cm)
Entries 10Mean x 1.3Mean y 0.5116RMS x 0.2872RMS y 0.132
PMT collection eff vs GC PMT Cone min tangent radius(cm)
(b) PMT array collection efficiency vs PMT Cone min innertangent radius (cm).
GC PMT Cone min tangent radius(cm)0.8 1 1.2 1.4 1.6 1.8
pmt
N
6
7
8
9
10
11
vs GC PMT Cone min tangent radius(cm)pmtN vs GC PMT Cone min tangent radius(cm)pmtN
Entries 10Mean x 1.3Mean y 8.595RMS x 0.2872RMS y 1.436
vs GC PMT Cone min tangent radius(cm)pmtN
(c) NPMT vs PMT Cone min inner tangent radius (cm).
GC PMT Cone min tangent radius(cm)0.8 1 1.2 1.4 1.6 1.8
pmt
/Np.
eN
1.8
2
2.2
2.4
2.6
vs GC PMT Cone min tangent radius(cm)pmt/Np.eN vs GC PMT Cone min tangent radius(cm)pmt
/Np.eN
Entries 10Mean x 1.3Mean y 2.161RMS x 0.2872RMS y 0.1961
vs GC PMT Cone min tangent radius(cm)pmt/Np.eN
(d) Np.e/NPMT vs PMT Cone min inner tangent radius (cm).
FIG. 17: Study of PMT Cone min inner tangent radius (cm).
– The cone length is defined as the height/length of the cone. If the length is too small, the slope of the conewill be large. If too large, it just wastes the cone.
18
GC PMT Cone length(cm)0 0.5 1 1.5 2 2.5
Mirr
or c
olle
ctio
n ef
f
0.86
0.88
0.9
0.92
0.94
0.96
0.98
1
1.02
1.04
1.06
Mirror collection eff vs GC PMT Cone length(cm) Mirror collection eff vs GC PMT Cone length(cm)
Entries 10Mean x 1.35Mean y 0.9573RMS x 0.8617RMS y 0.005975
Mirror collection eff vs GC PMT Cone length(cm)
(a) Mirror array collection efficiency vs PMT Cone length(cm).
GC PMT Cone length(cm)0 0.5 1 1.5 2 2.5
PM
T c
olle
ctio
n ef
f
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
PMT collection eff vs GC PMT Cone length(cm) PMT collection eff vs GC PMT Cone length(cm)
Entries 10Mean x 1.35Mean y 0.6339RMS x 0.8617RMS y 0.1193
PMT collection eff vs GC PMT Cone length(cm)
(b) PMT array collection efficiency vs PMT Cone length(cm).
GC PMT Cone length(cm)0 0.5 1 1.5 2 2.5
pmt
N
7
8
9
10
11
vs GC PMT Cone length(cm)pmtN vs GC PMT Cone length(cm)pmtN
Entries 10Mean x 1.35Mean y 9.874RMS x 0.8617RMS y 1.318
vs GC PMT Cone length(cm)pmtN
(c) NPMT vs PMT Cone length (cm).
GC PMT Cone length(cm)0 0.5 1 1.5 2 2.5
pmt
/Np.
eN
1.9
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
vs GC PMT Cone length(cm)pmt/Np.eN vs GC PMT Cone length(cm)pmt
/Np.eN
Entries 10Mean x 1.35Mean y 2.347RMS x 0.8617RMS y 0.1579
vs GC PMT Cone length(cm)pmt/Np.eN
(d) Np.e/NPMT vs PMT Cone length (cm).
FIG. 18: Study of PMT Cone length (cm).
• The larger the mirror radius is, the more the number of fired PMTs is if we keep the focal length defined asbefore as the half of the mirror radius.
19
GC Mirror radius(cm)60 80 100 120 140 160
Mirr
or c
olle
ctio
n ef
f
0.65
0.7
0.75
0.8
0.85
0.9
0.95
1
1.05
Mirror collection eff vs GC Mirror radius(cm) Mirror collection eff vs GC Mirror radius(cm)
Entries 10Mean x 105Mean y 0.8953RMS x 28.72RMS y 0.08415
Mirror collection eff vs GC Mirror radius(cm)
(a) Mirror array collection efficiency vs Mirror radius (cm).
GC Mirror radius(cm)60 80 100 120 140 160
PM
T c
olle
ctio
n ef
f
0.58
0.6
0.62
0.64
0.66
0.68
0.7
0.72
0.74
0.76
0.78
PMT collection eff vs GC Mirror radius(cm) PMT collection eff vs GC Mirror radius(cm)
Entries 10Mean x 105Mean y 0.6901RMS x 28.72RMS y 0.02395
PMT collection eff vs GC Mirror radius(cm)
(b) PMT array collection efficiency vs Mirror radius (cm).
GC Mirror radius(cm)60 80 100 120 140 160
pmt
N
5
6
7
8
9
10
11
12
vs GC Mirror radius(cm)pmtN vs GC Mirror radius(cm)pmtN
Entries 10Mean x 105Mean y 8.959RMS x 28.72RMS y 2.059
vs GC Mirror radius(cm)pmtN
(c) NPMT vs Mirror radius (cm).
GC Mirror radius(cm)60 80 100 120 140 160
pmt
/Np.
eN
2.2
2.4
2.6
2.8
3
3.2
3.4
vs GC Mirror radius(cm)pmt/Np.eN vs GC Mirror radius(cm)pmt
/Np.eN
Entries 10Mean x 105Mean y 2.733RMS x 28.72RMS y 0.2933
vs GC Mirror radius(cm)pmt/Np.eN
(d) Np.e/NPMT vs Mirror radius (cm).
FIG. 19: Study of Mirror radius (cm).
• In simulation, I set up four mirrors. Two in the middle are only rotated about Y-axis but the top and bottomone are not only rotated about Y-axis first but also rotated by ±α ◦about new Z-axis which is rotated by Y-axisfrom the old defined Z-axis.
20
GC Mirror 1/4 rotation angle about hor plane (deg)10 20 30 40 50
Mirr
or c
olle
ctio
n ef
f
0.75
0.8
0.85
0.9
0.95
1
Mirror collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg) Mirror collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg)
Entries 10Mean x 27.5Mean y 0.8683RMS x 14.36RMS y 0.03738
Mirror collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg)
(a) Mirror array collection efficiency vs Mirror 1/4 α (deg).
GC Mirror 1/4 rotation angle about hor plane (deg)10 20 30 40 50
PM
T c
olle
ctio
n ef
f
0.55
0.6
0.65
0.7
0.75
PMT collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg) PMT collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg)
Entries 10Mean x 27.5Mean y 0.6603RMS x 14.36RMS y 0.04279
PMT collection eff vs GC Mirror 1/4 rotation angle about hor plane (deg)
(b) PMT array collection efficiency vs Mirror 1/4 α (deg).
GC Mirror 1/4 rotation angle about hor plane (deg)10 20 30 40 50
pmt
N
8.5
9
9.5
10
10.5
11
11.5
vs GC Mirror 1/4 rotation angle about hor plane (deg)pmtN vs GC Mirror 1/4 rotation angle about hor plane (deg)pmt
N
Entries 10Mean x 27.5Mean y 10.12RMS x 14.36RMS y 0.5717
vs GC Mirror 1/4 rotation angle about hor plane (deg)pmtN
(c) NPMT vs Mirror 1/4 α (deg).
GC Mirror 1/4 rotation angle about hor plane (deg)10 20 30 40 50
pmt
/Np.
eN
2.1
2.2
2.3
2.4
2.5
2.6
2.7
vs GC Mirror 1/4 rotation angle about hor plane (deg)pmt
/Np.eN vs GC Mirror 1/4 rotation angle about hor plane (deg)pmt
/Np.eN
Entries 10Mean x 27.5Mean y 2.378RMS x 14.36RMS y 0.09767
vs GC Mirror 1/4 rotation angle about hor plane (deg)pmt
/Np.eN
(d) Np.e/NPMT vs Mirror 1/4 α (deg).
FIG. 20: Study of Mirror 1&4 rotation angle α (deg) about horizontal plane. Mirror 1 means the top mirror, 4 is thebottom mirror.
• Also I study the PMT response to the cherenkov photon.
• e− detection efficiency is defined as how many electrons are detected if known number of electrons N sample isshoot in gas Cherenkov detector. To detect electron on PMT array, we need to set number of PMTs as a cut.And use same cut, we can also calculate pion rejection factor which is defined as one pion is accidently treatedas an electron if known number of pions Nπ is scattered into gas Cherenkov detector. For example, electrondetector efficiency 99% means 99% of incoming electrons are detected by gas Cherenkov detector. Pion rejectionfactor 100 : 1 means one pion in 100 pions is thought as electron in gas Cherenkov detector.
– Active length is 70 cm.
– Active length is 45 cm.
• Space between PMT.
21
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34
35 36 37 38 39 40 41 42 43
44 45 46 47 48 49 50 51
52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68
69 70 71 72 73 74 75 76 77
78 79 80 81 82 83 84 85
86 87 88 89 90 91 92 93 94
95 96 97 98 99 100 101 102
103 104 105 106 107 108 109 110 111
112 113 114 115 116 117 118 119
120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136
137 138 139 140 141 142 143 144 145
146 147 148 149 150 151 152 153
154 155 156 157 158 159 160 161 162
163 164 165 166 167 168 169 170
171 172 173 174 175 176 177 178 179
180 181 182 183 184 185 186 187
188 189 190 191 192 193 194 195 196
197 198 199 200 201 202 203 204
205 206 207 208 209 210 211 212 213
214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230
231 232 233 234 235 236 237 238
239 240 241 242 243 244 245 246 247
248 249 250 251 252 253 254 255
256 257 258 259 260 261 262 263 264
265 266 267 268 269 270 271 272
273 274 275 276 277 278 279 280 281
282 283 284 285 286 287 288 289
290 291 292 293 294 295 296 297 298
299 300 301 302 303 304 305 306
307 308 309 310 311 312 313 314 315
316 317 318 319 320 321 322 323
324 325 326 327 328 329 330 331 332
333 334 335 336 337 338 339 340
341 342 343 344 345 346 347 348 349
350 351 352 353 354 355 356 357
358 359 360 361 362 363 364 365 366
367 368 369 370 371 372 373 374
375 376 377 378 379 380 381 382 383
384 385 386 387 388 389 390 391
392 393 394 395 396 397 398 399 400
401 402 403 404 405 406 407 408
409 410 411 412 413 414 415 416 417
418 419 420 421 422 423 424 425
426 427 428 429 430 431 432 433 434
435 436 437 438 439 440 441 442
443 444 445 446 447 448 449 450 451
452 453 454 455 456 457 458 459
460 461 462 463 464 465 466 467 468
469 470 471 472 473 474 475 476
477 478 479 480 481 482 483 484 485
486 487 488 489 490 491 492 493
494 495 496 497 498 499 500 501 502
503 504 505 506 507 508 509 510
(a) Event 13
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34
35 36 37 38 39 40 41 42 43
44 45 46 47 48 49 50 51
52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68
69 70 71 72 73 74 75 76 77
78 79 80 81 82 83 84 85
86 87 88 89 90 91 92 93 94
95 96 97 98 99 100 101 102
103 104 105 106 107 108 109 110 111
112 113 114 115 116 117 118 119
120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136
137 138 139 140 141 142 143 144 145
146 147 148 149 150 151 152 153
154 155 156 157 158 159 160 161 162
163 164 165 166 167 168 169 170
171 172 173 174 175 176 177 178 179
180 181 182 183 184 185 186 187
188 189 190 191 192 193 194 195 196
197 198 199 200 201 202 203 204
205 206 207 208 209 210 211 212 213
214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230
231 232 233 234 235 236 237 238
239 240 241 242 243 244 245 246 247
248 249 250 251 252 253 254 255
256 257 258 259 260 261 262 263 264
265 266 267 268 269 270 271 272
273 274 275 276 277 278 279 280 281
282 283 284 285 286 287 288 289
290 291 292 293 294 295 296 297 298
299 300 301 302 303 304 305 306
307 308 309 310 311 312 313 314 315
316 317 318 319 320 321 322 323
324 325 326 327 328 329 330 331 332
333 334 335 336 337 338 339 340
341 342 343 344 345 346 347 348 349
350 351 352 353 354 355 356 357
358 359 360 361 362 363 364 365 366
367 368 369 370 371 372 373 374
375 376 377 378 379 380 381 382 383
384 385 386 387 388 389 390 391
392 393 394 395 396 397 398 399 400
401 402 403 404 405 406 407 408
409 410 411 412 413 414 415 416 417
418 419 420 421 422 423 424 425
426 427 428 429 430 431 432 433 434
435 436 437 438 439 440 441 442
443 444 445 446 447 448 449 450 451
452 453 454 455 456 457 458 459
460 461 462 463 464 465 466 467 468
469 470 471 472 473 474 475 476
477 478 479 480 481 482 483 484 485
486 487 488 489 490 491 492 493
494 495 496 497 498 499 500 501 502
503 504 505 506 507 508 509 510
(b) Event 16
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34
35 36 37 38 39 40 41 42 43
44 45 46 47 48 49 50 51
52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68
69 70 71 72 73 74 75 76 77
78 79 80 81 82 83 84 85
86 87 88 89 90 91 92 93 94
95 96 97 98 99 100 101 102
103 104 105 106 107 108 109 110 111
112 113 114 115 116 117 118 119
120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136
137 138 139 140 141 142 143 144 145
146 147 148 149 150 151 152 153
154 155 156 157 158 159 160 161 162
163 164 165 166 167 168 169 170
171 172 173 174 175 176 177 178 179
180 181 182 183 184 185 186 187
188 189 190 191 192 193 194 195 196
197 198 199 200 201 202 203 204
205 206 207 208 209 210 211 212 213
214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230
231 232 233 234 235 236 237 238
239 240 241 242 243 244 245 246 247
248 249 250 251 252 253 254 255
256 257 258 259 260 261 262 263 264
265 266 267 268 269 270 271 272
273 274 275 276 277 278 279 280 281
282 283 284 285 286 287 288 289
290 291 292 293 294 295 296 297 298
299 300 301 302 303 304 305 306
307 308 309 310 311 312 313 314 315
316 317 318 319 320 321 322 323
324 325 326 327 328 329 330 331 332
333 334 335 336 337 338 339 340
341 342 343 344 345 346 347 348 349
350 351 352 353 354 355 356 357
358 359 360 361 362 363 364 365 366
367 368 369 370 371 372 373 374
375 376 377 378 379 380 381 382 383
384 385 386 387 388 389 390 391
392 393 394 395 396 397 398 399 400
401 402 403 404 405 406 407 408
409 410 411 412 413 414 415 416 417
418 419 420 421 422 423 424 425
426 427 428 429 430 431 432 433 434
435 436 437 438 439 440 441 442
443 444 445 446 447 448 449 450 451
452 453 454 455 456 457 458 459
460 461 462 463 464 465 466 467 468
469 470 471 472 473 474 475 476
477 478 479 480 481 482 483 484 485
486 487 488 489 490 491 492 493
494 495 496 497 498 499 500 501 502
503 504 505 506 507 508 509 510
(c) Event 23
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34
35 36 37 38 39 40 41 42 43
44 45 46 47 48 49 50 51
52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68
69 70 71 72 73 74 75 76 77
78 79 80 81 82 83 84 85
86 87 88 89 90 91 92 93 94
95 96 97 98 99 100 101 102
103 104 105 106 107 108 109 110 111
112 113 114 115 116 117 118 119
120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136
137 138 139 140 141 142 143 144 145
146 147 148 149 150 151 152 153
154 155 156 157 158 159 160 161 162
163 164 165 166 167 168 169 170
171 172 173 174 175 176 177 178 179
180 181 182 183 184 185 186 187
188 189 190 191 192 193 194 195 196
197 198 199 200 201 202 203 204
205 206 207 208 209 210 211 212 213
214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230
231 232 233 234 235 236 237 238
239 240 241 242 243 244 245 246 247
248 249 250 251 252 253 254 255
256 257 258 259 260 261 262 263 264
265 266 267 268 269 270 271 272
273 274 275 276 277 278 279 280 281
282 283 284 285 286 287 288 289
290 291 292 293 294 295 296 297 298
299 300 301 302 303 304 305 306
307 308 309 310 311 312 313 314 315
316 317 318 319 320 321 322 323
324 325 326 327 328 329 330 331 332
333 334 335 336 337 338 339 340
341 342 343 344 345 346 347 348 349
350 351 352 353 354 355 356 357
358 359 360 361 362 363 364 365 366
367 368 369 370 371 372 373 374
375 376 377 378 379 380 381 382 383
384 385 386 387 388 389 390 391
392 393 394 395 396 397 398 399 400
401 402 403 404 405 406 407 408
409 410 411 412 413 414 415 416 417
418 419 420 421 422 423 424 425
426 427 428 429 430 431 432 433 434
435 436 437 438 439 440 441 442
443 444 445 446 447 448 449 450 451
452 453 454 455 456 457 458 459
460 461 462 463 464 465 466 467 468
469 470 471 472 473 474 475 476
477 478 479 480 481 482 483 484 485
486 487 488 489 490 491 492 493
494 495 496 497 498 499 500 501 502
503 504 505 506 507 508 509 510
(d) Event 25
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34
35 36 37 38 39 40 41 42 43
44 45 46 47 48 49 50 51
52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68
69 70 71 72 73 74 75 76 77
78 79 80 81 82 83 84 85
86 87 88 89 90 91 92 93 94
95 96 97 98 99 100 101 102
103 104 105 106 107 108 109 110 111
112 113 114 115 116 117 118 119
120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136
137 138 139 140 141 142 143 144 145
146 147 148 149 150 151 152 153
154 155 156 157 158 159 160 161 162
163 164 165 166 167 168 169 170
171 172 173 174 175 176 177 178 179
180 181 182 183 184 185 186 187
188 189 190 191 192 193 194 195 196
197 198 199 200 201 202 203 204
205 206 207 208 209 210 211 212 213
214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230
231 232 233 234 235 236 237 238
239 240 241 242 243 244 245 246 247
248 249 250 251 252 253 254 255
256 257 258 259 260 261 262 263 264
265 266 267 268 269 270 271 272
273 274 275 276 277 278 279 280 281
282 283 284 285 286 287 288 289
290 291 292 293 294 295 296 297 298
299 300 301 302 303 304 305 306
307 308 309 310 311 312 313 314 315
316 317 318 319 320 321 322 323
324 325 326 327 328 329 330 331 332
333 334 335 336 337 338 339 340
341 342 343 344 345 346 347 348 349
350 351 352 353 354 355 356 357
358 359 360 361 362 363 364 365 366
367 368 369 370 371 372 373 374
375 376 377 378 379 380 381 382 383
384 385 386 387 388 389 390 391
392 393 394 395 396 397 398 399 400
401 402 403 404 405 406 407 408
409 410 411 412 413 414 415 416 417
418 419 420 421 422 423 424 425
426 427 428 429 430 431 432 433 434
435 436 437 438 439 440 441 442
443 444 445 446 447 448 449 450 451
452 453 454 455 456 457 458 459
460 461 462 463 464 465 466 467 468
469 470 471 472 473 474 475 476
477 478 479 480 481 482 483 484 485
486 487 488 489 490 491 492 493
494 495 496 497 498 499 500 501 502
503 504 505 506 507 508 509 510
(e) Event 39
FIG. 21: Event Display
22
as cutPMTN2 4 6 8 10 12 14 16
e- e
ffici
ency
0.2
0.4
0.6
0.8
1
e- detection effiencye- detection effiency
(a) e− detector efficiency
z(cm) horizon
-20 -15 -10 -5 0 5 10 15 20
y(cm
) ve
rtic
al
-80
-60
-40
-20
0
20
40
60
80
Particle y vs z with mirror eff<0.9 in DCSParticle y vs z with mirror eff<0.9 in DCS
dz(deg) horizon
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6
dy(d
eg)
vert
ical
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
Particle dir y vs dir z with mirror eff<0.9 in DCSParticle dir y vs dir z with mirror eff<0.9 in DCS
(b) π− rejection factor
as cutPMTN2 4 6 8 10 12 14 16
e+ r
ejec
tion
fact
or
10
20
30
40
50
60
e+ rejection factore+ rejection factor
(c) e+ rejection factor
z(cm) horizon
-20 -15 -10 -5 0 5 10 15 20
y(cm
) ve
rtic
al
-80
-60
-40
-20
0
20
40
60
80
Particle y vs z with mirror eff<0.9 in DCSParticle y vs z with mirror eff<0.9 in DCS
dz(deg) horizon
-0.6 -0.4 -0.2 0 0.2 0.4
dy(d
eg)
vert
ical
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
Particle dir y vs dir z with mirror eff<0.9 in DCSParticle dir y vs dir z with mirror eff<0.9 in DCS
(d) π+ rejection factor
FIG. 22: Efficiency of incoming particles when active length= 70 cm.
23
as cutPMTN2 4 6 8 10 12 14 16
e- e
ffici
ency
0
0.2
0.4
0.6
0.8
1
e- detection effiencye- detection effiency
(a) e− detector efficiency
z(cm) horizon
-20 -15 -10 -5 0 5 10 15 20
y(cm
) ve
rtic
al
-80
-60
-40
-20
0
20
40
60
Particle y vs z with mirror eff<0.9 in DCSParticle y vs z with mirror eff<0.9 in DCS
dz(deg) horizon
-0.4 -0.2 0 0.2 0.4 0.6
dy(d
eg)
vert
ical
-0.4
-0.2
0
0.2
0.4
0.6
Particle dir y vs dir z with mirror eff<0.9 in DCSParticle dir y vs dir z with mirror eff<0.9 in DCS
(b) π− rejection factor
as cutPMTN2 4 6 8 10 12 14 16
e+ r
ejec
tion
fact
or
100
200
300
400
500
600
e+ rejection factore+ rejection factor
(c) e+ rejection factor
z(cm) horizon
-20 -15 -10 -5 0 5 10 15 20
y(cm
) ve
rtic
al
-80
-60
-40
-20
0
20
40
60
80
Particle y vs z with mirror eff<0.9 in DCSParticle y vs z with mirror eff<0.9 in DCS
dz(deg) horizon
-0.2 -0.1 0 0.1 0.2
dy(d
eg)
vert
ical
-0.4
-0.2
0
0.2
0.4
0.6
Particle dir y vs dir z with mirror eff<0.9 in DCSParticle dir y vs dir z with mirror eff<0.9 in DCS
(d) π+ rejection factor
FIG. 23: Efficiency of incoming particles when active length= 45 cm.
24
Half space(cm)1.4 1.6 1.8 2 2.2 2.4
PM
T c
olle
ctio
n ef
f
0.75
0.8
0.85
0.9
0.95
1
PMT collection eff vs Half space(cm) PMT collection eff vs Half space(cm)
Entries 10Mean x 1.9Mean y 0.8962RMS x 0.2872RMS y 0.05211
PMT collection eff vs Half space(cm)
(a) PMT array collection efficiency vs PMT Space (cm).
Half space(cm)1.4 1.6 1.8 2 2.2 2.4
pmt
N
8
9
10
11
12
13
14
vs Half space(cm)pmtN vs Half space(cm)pmtN
Entries 10Mean x 1.9Mean y 10.75RMS x 0.2872RMS y 1.751
vs Half space(cm)pmtN
(b) NPMT vs PMT Space (cm).
Half space(cm)1.4 1.6 1.8 2 2.2 2.4
pmt
/Np.
eN
2.4
2.6
2.8
3
3.2
3.4
3.6
3.8
vs Half space(cm)pmt/Np.eN vs Half space(cm)pmt/Np.eN
Entries 10Mean x 1.9Mean y 3.085RMS x 0.2872RMS y 0.3542
vs Half space(cm)pmt/Np.eN
(c) Np.e/NPMT vs PMT Space (cm).
Half space(cm)1.4 1.6 1.8 2 2.2 2.4
Det
ectio
n ef
ficie
ncy
0.92
0.94
0.96
0.98
1
1.02
1.04
1.06
8)≥pe
Detection efficiency (N 8)≥pe
Detection efficiency (N
(d) e− efficiency vs PMT Space (cm).
FIG. 24: Study of PMT Space (cm). 2x is the spacing between the center of adjecent PMTs.
25
• The position distribution of photons hit on the PMT from different part of mirror.
0
5
10
15
20
25
30
35
ColPMT3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8
Row
PM
T
10
20
30
40
50
for left edge of mirrorCol vs PMTRowPMT h2_0Entries 518Mean x 5.046Mean y 35.94RMS x 0.6705RMS y 16.19
for left edge of mirrorCol vs PMTRowPMT
ColPMT0 1 2 3 4 5 6 7 8 9 10
Row
PM
T
0
10
20
30
40
50
60
for right edge of mirrorCol vs PMTRowPMT h2_1Entries 3953Mean x 7.477Mean y 33.85RMS x 1.476RMS y 16.6
for right edge of mirrorCol vs PMTRowPMT
0
200
400
600
800
1000
1200
1400
ColPMT0 1 2 3 4 5 6 7 8 9 10
Row
PM
T
0
10
20
30
40
50
60
for whole mirrorCol vs PMTRowPMT h2_2Entries 133834Mean x 5.942Mean y 27.96RMS x 1.086RMS y 16.37
for whole mirrorCol vs PMTRowPMT
FIG. 25: Top left figure is the PMT row number versus PMT column number when photons are scattered from theleft edge of mirror. Top right is from the right edge of mirror. Bottom left is from the whole mirror.
26
cutpeN5 10 15 20 25 30
e-η
0
0.2
0.4
0.6
0.8
1
1.2
--15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( --15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0
0.2
0.4
0.6
0.8
1
1.2
-15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( -15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0.2
0.4
0.6
0.8
1
1.2
--15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( --15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0.2
0.4
0.6
0.8
1
1.2
-15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( -15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0
0.2
0.4
0.6
0.8
1
1.2
--15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( --15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0.2
0.4
0.6
0.8
1
1.2
-15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( -15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0
0.2
0.4
0.6
0.8
1
1.2
--15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( --15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
cutpeN5 10 15 20 25 30
e-η
0.2
0.4
0.6
0.8
1
1.2
-15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency ( -15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs Ne-
ηe- detection efficiency (
FIG. 26: This is the electron detection efficiency (ηe−) versus Np.e cut for different part of mirror. Each row of allthese eight figures means which mirror starting from top to bottom. Left and right mean which part of the mirror,
left part or right part.
For π−,
27
020406080100120140160180200220240
ColPMT2 3 4 5 6 7 8 9 10
Row
PM
T
0
10
20
30
40
50
60
for left edge of mirrorCol vs PMTRowPMT h2_0Entries 15163Mean x 5.977Mean y 30.2RMS x 0.722RMS y 15.95
for left edge of mirrorCol vs PMTRowPMT
ColPMT0 1 2 3 4 5 6 7 8 9 10
Row
PM
T
0
10
20
30
40
50
60
for right edge of mirrorCol vs PMTRowPMT h2_1Entries 48573Mean x 7.425Mean y 29.76RMS x 0.6208RMS y 17.46
for right edge of mirrorCol vs PMTRowPMT
0
2000
4000
6000
8000
10000
ColPMT0 1 2 3 4 5 6 7 8 9 10
Row
PM
T
0
10
20
30
40
50
60
for whole mirrorCol vs PMTRowPMT h2_2Entries 799526Mean x 6.031Mean y 26.79RMS x 0.8695RMS y 16.5
for whole mirrorCol vs PMTRowPMT
FIG. 27: Top left figure is the PMT row number versus PMT column number when photons are scattered from theleft edge of mirror. Top right is from the right edge of mirror. Bottom left is from the whole mirror.
28
cutpeN5 10 15 20 25 30
-πη
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
--15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs N-π
η- efficiency (π --15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
-15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs N-π
η- efficiency (π -15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
--15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs N-π
η- efficiency (π --15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
-15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs N-π
η- efficiency (π -15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
--15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs N-π
η- efficiency (π --15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
-15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs N-π
η- efficiency (π -15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
--15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs N-π
η- efficiency (π --15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs N-π
η- efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
-15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs N-π
η- efficiency (π -15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs N-π
η- efficiency (π
FIG. 28: This is the π− efficiency (ηπ−) versus Np.e cut for different part of mirror. Each row of all these eightfigures means which mirror starting from top to bottom. Left and right mean which part of the mirror, left part or
right part.
29
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
--15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
--15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
-15.5227|<15.5227&&Mirror=1mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
--15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
--15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
-15.5227|<15.5227&&Mirror=2mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
--15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
--15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
-15.5227|<15.5227&&Mirror=3mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
--15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
--15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
P (MeV/c)1600 1800 2000 2200 2400 2600 2800 3000 3200
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
-15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
=5peN=8
peN
=11pe
N=14
peN
=17pe
N=20
peN
=23pe
N=26
peN
=29pe
N
-15.5227|<15.5227&&Mirror=4mir
cut with |Horpe
) vs P (MeV/c) for different N-π
η- efficiency (π
FIG. 29: This is the π− efficiency (ηπ−) versus P (MeV/c) for different Np.e cut for different part of mirror. Eachrow of all these eight figures means which mirror starting from top to bottom. Left and right mean which part of
the mirror, left part or right part.
30
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
--15.5227|<15.5227&&Mirror=1mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π --15.5227|<15.5227&&Mirror=1mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=1mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π -15.5227|<15.5227&&Mirror=1mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
--15.5227|<15.5227&&Mirror=2mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π --15.5227|<15.5227&&Mirror=2mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=2mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π -15.5227|<15.5227&&Mirror=2mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
--15.5227|<15.5227&&Mirror=3mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π --15.5227|<15.5227&&Mirror=3mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-15.5227|<15.5227&&Mirror=3mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π -15.5227|<15.5227&&Mirror=3mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
--15.5227|<15.5227&&Mirror=4mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π --15.5227|<15.5227&&Mirror=4mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
cutpeN5 10 15 20 25 30
-πη
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
-15.5227|<15.5227&&Mirror=4mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π -15.5227|<15.5227&&Mirror=4mir
for P=3211.89 MeV/c with |Horpe
) vs N-π
η- detection efficiency (π
FIG. 30: This is the π− efficiency (ηπ−) versus Np.e for P = 3.2 GeV for different part of mirror. Each row of allthese eight figures means which mirror starting from top to bottom. Left and right mean which part of the mirror,
left part or right part.
Primary parameters are used in the GEANT4 simulation.
[PrimaryGeneratorAction]Particle Name: e-Particle Min Energy: 1600 MeVParticle Max Energy: 3300 MeVParticle Distribution: Uniform Distribution[DetectorConstruction]World Name: WorldWorld Shape: G4BoxWorld Full Size: (1000 cm, 1000 cm, 1000 cm)World Material: VacuumTarget Name: TargetTarget Shape: G4TubsTarget Length: 50 cmTarget Radius: 2 cm
31
Target Material: VacuumTarget Color: BlackBigbite detector package scattering angle: -30 degBigbite detector package bending angle: 10 degDistance from Bigbite magnet center to target center: 187.5 cmDistance from Bigbite magnet center to gem 1 center: 93 cmDistance from Bigbite magnet center to gem 2 center: 99 cmDistance from Bigbite magnet center to gas cherenkov center: 165 cmDistance from Bigbite magnet center to mwdc 1 center: 221 cmDistance from Bigbite magnet center to mwdc 2 center: 230 cmDistance from Bigbite magnet center to preshower center: 245 cmDistance from Bigbite magnet center to shower center: 275 cmBigbite magnet gap/width: 25 cmBigbite magnet magnetic field: 1.2 teslaBigbite magnet corner radius: 28.5 cmBigbite magnet corner bending angle: 20 degBigbite magnet thickness: 20 cmBigbite magnet top box full size: (45.8601 cm, 28.5 cm, 20 cm)Bigbite magnet top box material: Carbon_SteelBigbite magnet top box color: WhiteBigbite magnet bottom box full size: (81.1967 cm, 28.5 cm, 20 cm)Bigbite magnet bottom box material: Carbon_SteelBigbite magnet bottom box color: WhiteBigbite magnet entrance box full size: (28.5 cm, 89 cm, 20 cm)Bigbite magnet entrance box material: Carbon_SteelBigbite magnet entrance box color: WhiteBigbite magnet exit box full size: (28.5 cm, 111.404 cm, 20 cm)Bigbite magnet exit box material: Carbon_SteelBigbite magnet exit box color: WhiteBigbite magnet top-left corner material: Carbon_SteelBigbite magnet top-left corner color: WhiteBigbite magnet bottom-left corner material: Carbon_SteelBigbite magnet bottom-left corner color: WhiteBigbite magnet top-right corner material: Carbon_SteelBigbite magnet top-right corner color: WhiteBigbite magnet bottom-right corner material: Carbon_SteelBigbite magnet bottom-right corner color: WhiteBigbite magnet electromagnet trapezoid material: Carbon_SteelBigbite magnet electromagnet trapezoid color: BlueBigbite magnet magnetic field trapezoid material: VacuumBigbite magnet magnetic field trapezoid color: MagentaGEM 1 frame full size: (4 cm, 150 cm, 12 cm)GEM 1 frame material: Carbon_SteelGEM 1 frame color: WhiteGEM 1 full size: (4 cm, 150 cm, 40 cm)GEM 1 material: VacuumGEM 1 color: GrayGEM 2 frame full size: (4 cm, 150 cm, 12 cm)GEM 2 frame material: Carbon_SteelGEM 2 frame color: WhiteGEM 2 full size: (4 cm, 150 cm, 40 cm)GEM 2 material: VacuumGEM 2 color: GrayMWDC 1 frame full size: (4 cm, 200 cm, 12 cm)MWDC 1 frame material: Carbon_SteelMWDC 1 frame color: WhiteMWDC 1 full size: (4 cm, 200 cm, 50 cm)MWDC 1 material: Vacuum
32
MWDC 1 color: GrayMWDC 2 frame full size: (4 cm, 200 cm, 12 cm)MWDC 2 frame material: Carbon_SteelMWDC 2 frame color: WhiteMWDC 2 full size: (4 cm, 200 cm, 50 cm)MWDC 2 material: VacuumMWDC 2 color: GrayPreShower full size: (10 cm, 210 cm, 74 cm)PreShower material: VacuumPreShower color: GrayShower full size: (34 cm, 221 cm, 85 cm)Shower material: VacuumShower color: GrayGas Cherenkov tank Name: GC_TankGas Cherenkov tank Shape: G4BoxGas Cherenkov tank Full Size: (100 cm, 200 cm, 153.533 cm)Gas Cherenkov tank active length: 70 cmGas Cherenkov tank space after mirror: 2 cmGas Cherenkov tank Material: C4F8OGas Cherenkov tank Pressure: 1.5 atmosphereGas Cherenkov tank Color: CyanGas Cherenkov tank Visibility: trueGas Cherenkov tank ForceWireframe: trueGas Cherenkov PMT Box Name: GC_PMT_BoxGas Cherenkov PMT Box Shape: G4BoxGas Cherenkov PMT Box Gap Size: (15 cm, 5 cm, 5 cm)Gas Cherenkov PMT Box Full Size: (28.45 cm, 191.436 cm, 40.516 cm)Gas Cherenkov PMT Box Thickness: 0.635 cmGas Cherenkov PMT Box Angle of rotation about Y-axis: 55 degGas Cherenkov PMT Box Distance between front surface of PMT and mirror center: 65 cmGas Cherenkov PMT Box Material: Stainless_SteelGas Cherenkov PMT Box Color: GreyGas Cherenkov PMT Box Visibility: trueGas Cherenkov PMT Box ForceWireframe: trueGas Cherenkov PMT Box Jail Name: GC_PMT_Box_JailGas Cherenkov PMT Box Jail Shape: G4BoxGas Cherenkov PMT Box Jail Full Size: (0.1 cm, 0.25 cm, 40.516 cm)Gas Cherenkov PMT Box Jail Space: 2.5 cmGas Cherenkov Number of PMT Box Jail Bars: 76Gas Cherenkov PMT Box Jail Material: AlGas Cherenkov PMT Box Jail Color: BlackGas Cherenkov PMT Box Jail Visibility: trueGas Cherenkov PMT Box Jail ForceWireframe: trueGas Cherenkov PMT Name: GC_PMTGas Cherenkov PMT Shape: G4TubsGas Cherenkov PMT Cover Radius: 1.751 cmGas Cherenkov PMT Active Radius: 1.25 cmSo Gas Cherenkov PMT Active area ratio: 0.509621Gas Cherenkov PMT Length: 13.45 cmGas Cherenkov PMT Number of rows: 60Gas Cherenkov PMT Min Number of PMTs in a row: 8Gas Cherenkov PMT Min Wavelength: 275 (nm)Gas Cherenkov PMT Max Wavelength: 635 (nm)Gas Cherenkov PMT Quantum Efficiency Fit Parameters:p0=-74.2442 p1=0.968278 p2=-0.00521893 p3=1.49183e-05 p4=-2.38068e-08 p5=2.00603e-11 p6=-6.96098e-15Gas Cherenkov Photon-electron threshold (number of p.e): 0.5Gas Cherenkov PMT Material: AlGas Cherenkov PMT Color: Blue
33
Gas Cherenkov PMT Visibility: trueGas Cherenkov PMT Cover Color: GreyGas Cherenkov PMT Cover Visibility: falseGas Cherenkov PMT Row 1 Col 1: (0,-89.4682,-14.008) (cm)Gas Cherenkov PMT Row 2 Col 1: (0,-86.4354,-12.257) (cm)Horizontal space of PMT: 3.502 cmVertical space of PMT: 3.03282 cmGas Cherenkov PMT Cone Name: GC_PMT_ConeGas Cherenkov PMT Cone Shape: G4PolyhedraGas Cherenkov PMT Cone Max Inner Radius: 1.75 cmGas Cherenkov PMT Cone Min Inner Radius: 1.25 cmGas Cherenkov PMT Cone Length: 1 cmGas Cherenkov PMT Cone Thickness: 0.001 cmGas Cherenkov PMT Cone Reflectivity: 0.8Gas Cherenkov PMT Cone Material: GlassGas Cherenkov PMT Cone Color: YellowGas Cherenkov PMT Cone Visibility: trueGas Cherenkov Number of mirrors: 4Gas Cherenkov Mirror 1 Name: GC_Mirror_1Gas Cherenkov Mirror 1 Shape: CylinderGas Cherenkov Mirror 1 Radius: 130 cmGas Cherenkov Mirror 1 Horizontal Full Size: 70 cmGas Cherenkov Mirror 1 Vertical Full Size: 40 cmGas Cherenkov Mirror 1 Thickness: 0.635 cmGas Cherenkov Mirror 1 Angle of rotation about Y-axis: 27.5 degGas Cherenkov Mirror 1 Angle of rotation about new-axis(0.461749,0,0.887011): 14.1 degGas Cherenkov Mirror 1 Offset relative to center of tank: (20 cm, 80 cm, 0 cm)Gas Cherenkov Mirror 1 Offset along new x-axis(0.887011,0,-0.461749): -4.8723 cmGas Cherenkov Mirror 1 new Offset relative to center of tank: (15.6782 cm, 80 cm, 2.24978 cm)Gas Cherenkov Mirror 1 Reflectivity: 0.8Gas Cherenkov Mirror 1 Material: GlassGas Cherenkov Mirror 1 Color: BlueGas Cherenkov Mirror 1 Visibility: trueGas Cherenkov Mirror 2 Name: GC_Mirror_2Gas Cherenkov Mirror 2 Shape: CylinderGas Cherenkov Mirror 2 Radius: 130 cmGas Cherenkov Mirror 2 Horizontal Full Size: 70 cmGas Cherenkov Mirror 2 Vertical Full Size: 60 cmGas Cherenkov Mirror 2 Thickness: 0.635 cmGas Cherenkov Mirror 2 Angle of rotation about Y-axis: 27.5 degGas Cherenkov Mirror 2 Angle of rotation about new-axis(0.461749,0,0.887011): 0 degGas Cherenkov Mirror 2 Offset relative to center of tank: (20 cm, 30 cm, 0 cm)Gas Cherenkov Mirror 2 no Offset along new x-axis: 0Gas Cherenkov Mirror 2 Reflectivity: 0.8Gas Cherenkov Mirror 2 Material: GlassGas Cherenkov Mirror 2 Color: RedGas Cherenkov Mirror 2 Visibility: trueGas Cherenkov Mirror 3 Name: GC_Mirror_3Gas Cherenkov Mirror 3 Shape: CylinderGas Cherenkov Mirror 3 Radius: 130 cmGas Cherenkov Mirror 3 Horizontal Full Size: 70 cmGas Cherenkov Mirror 3 Vertical Full Size: 60 cmGas Cherenkov Mirror 3 Thickness: 0.635 cmGas Cherenkov Mirror 3 Angle of rotation about Y-axis: 27.5 degGas Cherenkov Mirror 3 Angle of rotation about new-axis(0.461749,0,0.887011): 0 degGas Cherenkov Mirror 3 Offset relative to center of tank: (20 cm, -30 cm, 0 cm)Gas Cherenkov Mirror 3 no Offset along new x-axis: 0Gas Cherenkov Mirror 3 Reflectivity: 0.8
34
Gas Cherenkov Mirror 3 Material: GlassGas Cherenkov Mirror 3 Color: RedGas Cherenkov Mirror 3 Visibility: trueGas Cherenkov Mirror 4 Name: GC_Mirror_4Gas Cherenkov Mirror 4 Shape: CylinderGas Cherenkov Mirror 4 Radius: 130 cmGas Cherenkov Mirror 4 Horizontal Full Size: 70 cmGas Cherenkov Mirror 4 Vertical Full Size: 40 cmGas Cherenkov Mirror 4 Thickness: 0.635 cmGas Cherenkov Mirror 4 Angle of rotation about Y-axis: 27.5 degGas Cherenkov Mirror 4 Angle of rotation about new-axis(0.461749,0,0.887011): -14.1 degGas Cherenkov Mirror 4 Offset relative to center of tank: (20 cm, -80 cm, 0 cm)Gas Cherenkov Mirror 4 Offset along new x-axis(0.887011,0,-0.461749): -4.8723 cmGas Cherenkov Mirror 4 new Offset relative to center of tank: (15.6782 cm, -80 cm, 2.24978 cm)Gas Cherenkov Mirror 4 Reflectivity: 0.8Gas Cherenkov Mirror 4 Material: GlassGas Cherenkov Mirror 4 Color: BlueGas Cherenkov Mirror 4 Visibility: true
1. V. Nelyubin. A GEANT Simulation of Background Rate in Quartz Window of PMT XP4508 in Cherenkov
Detector. 2011.2. P. Degtyarenko. Neutron Note.3. B. Wojtsekhowski. private communication. 2012.
Related Documents
