Download - HES-HKS analysis meeting
HES-HKS analysis meeting
Toshiyuki Gogami10Jan2014
Contents
• About missing mass resolution• Blind analysis• Resolution and linearity balance• Response function
• Missing mass status• Binding energy and cross section• 12
ΛB, 10ΛBe and 7
ΛHe
Missing mass estimation by the full-modeled Monte Carlo simulation
Achievable resolutionHyperon Hypernucleus
Target [mg/cm2]
Intrinsic Mass offset due to energy loss
Matrix z-dependence (B)
Simulated total resolution (A)
Achievable resolution (A-B)
Present work(Toshi’s anlysis)
Λ CH2 (450) 830 1000 730 2100 1380 16007
ΛHe 7Li (184.0) 440 260 550 1300 750 13009
ΛLi 9Be(188.1) 440 260 170 740 560 Not yet10
ΛBe 10B (56.1) 430 80 40 590 550 80012
ΛB 12C (87.5) 430 130 80 620 540 89052
ΛV 52Cr (134.0) 430 160 30 630 600 Not yet
Part of the z-dependence (Λ, Σ0 and 12ΛB) is absorbed by the matrices in a matrix tuning.
Effects of z-dependence absorption for other hypernuclei are not trivial. Blind analysis
( FWHM, Unit: keV )
Blind analysis
• Width and linearity balance• Matrix z-dependence (Λ,Σ0) absorption effect for hypernuclei
• Response function
Flow chartInitial matrices(not distorted)
Tuned matrices
Tune
Λ, Σ0 and hypernucei
Λ, Σ0 and hypernuceiAbsorbing effects of • z-dependence• Asymmetry shape• Etc.
Compare after tuningΛ + B.G.Σ0 + B.G.12
ΛB s-shell
Generated
Results
FWHM
[keV
]
ΔMM
[keV
]
Mean value displacement Width
Λ, Σ0, 12ΛB
Λ, Σ0
Λ, Σ0, 12ΛBΛ, Σ0
ΔMM < 130 keV 500 ~ 700 keV (12ΛB, 10
ΛB, 52ΛV)
~ 1000 keV (7ΛHe)
~ 1500 keV (Λ, Σ0) Achieved simultaneously !
Λ + B.G.Σ0 + B.G.12
ΛB s-shellNo matrix distortion+
Achievable resolutions
Response function
Missing mass status
12C(e,e’K+)12ΛB
7Li(e,e’K+)7ΛHe
10B(e,e’K+)10ΛBe
9Be(e,e’K+)9ΛLi
52Cr(e,e’K+)52ΛV
12C(e,e’K+)12ΛB
7Li(e,e’K+)7ΛHe
10B(e,e’K+)10ΛBe
9Be(e,e’K+)9ΛLi
Accidental background
52Cr(e,e’K+)52ΛV
Binding energy and Cross section• About cross section• Definition• Cut conditions• Efficiencies and correction factors
• Results• 12C(γ*,K+)12
ΛB• 7Li(γ*,K+)7
ΛHe• 10B(γ*,K+)10
ΛBe
Definition of differential cross section
Number of virtual photonincluding HES acceptance
Number of target protons EfficienciesHKS acceptance
Cut conditions
• 0.80 < pe < 0.98 [GeV/c]
• Abs(m2-m2K) < 0.3
• -1.0 < ctime < 1.0
Efficiencies and correction factors• Efficiencies• DAQ• Trigger• Tracking• K+ selection
• AC, WC, m2,
• Correction factors• K+ decay (momentum dependent)• Solid angle (momentum dependent)• K+ absorption • Event loss due to matrix and large energy loss (not included for the present work)
• Already studied by Fujita ~ 5- 10%
12C target
RemarksEfficiencies are different
between low and high current data
Two set of HES collimator positions are used.
Differential cross section of 12C(γ*,K+)12
ΛB
Peak -B [MeV] Number of event
Cross section [nb/sr]
1 -11.40 ± 0.03 657±26 83 ±3
3 -8.37 ± 0.10 135±11 17 ±1
4 -5.15 ± 0.18 118±11 15 ±1
5 -1.67 ± 0.23 116±11 14 ±1
2 -0.38 ± 0.04 631±25 82 ±3
6 +0.82 ± 0.09 240±15 31 ±2
Only statistical errors
( FWHM ~ 0.89 MeV )
12ΛB comparison
Experiment -BΛ [MeV] Cross section [nb/sr]
E05-115 -11.40 ± 0.03 83 ± 3
E01-011 -11.40 ± 0.01 ± 0.04 101 ± 4.2 (+ 38 – 31)
E89-009 -11.52 ± 0.35 140 ± 17 ± 18
Emulsion -11.37 ± 0.06 N/A
SΛ
Experiment -BΛ [MeV] Cross section [nb/sr]
E05-115 -0.38 ± 0.04 82 ± 3
E01-011 -0.41 ± 0.01 ± 0.13 94 ± 4.0 ±35
E89-009 -0.49 ± 0.16 N/A
pΛ
7Li targetRemarksTarget thickness (Three values)
Shichijo: 184.0 mg/cm2
ELOGWeight and area: 331.2 mg/cm2
Oil ? Nitriding ? Thickness and density: 207 mg/cm2
• Nitriding test• Check Brems. Rate in HES• Etc.
Need to be done !!!!
Differential cross section of 7Li(γ*,K+)7
ΛHe
Peak -B [MeV] Number of event
Cross section [nb/sr]
1 -5.28 ± 0.14 482±22 12.4 ±0.5
2 -3.50 ± 0.14 271±16 7.0 ±0.4
( FWHM ~ 1.3 MeV )
7ΛHe comparison
(FWHM ~ 1.3 MeV) -5.36 without CSB-5.16 with CSB
Peak -B [MeV] Number of event
Cross section [nb/sr]
1 -5.28 ± 0.14 482±22 12.4 ±0.5
2 -3.50 ± 0.14 271±16 7.0 ±0.4
( FWHM ~ 1.3 MeV )
Hiyama’s calc.
10B target
Differential cross section of 10B(γ*,K+)10
ΛBe
Peak -B [MeV] Number of event
Cross section [nb/sr]
1 -8.66 ± 0.08 141±12 11.6 ±0.9
2 -7.81 ± 0.23 51±7 4.3 ±0.7
3 -6.08 ± 0.09 139±12 11.8 ±1.0
4 -5.03 ± 0.14 78±9 6.5 ±0.7
5 -1.98 ± 0.10 156±13 13.0 ±0.9
6 -0.11 ± 0.16 123±11 10.0 ±0.8
7 2.23 ± 0.07 188±14 15.9 ±1.1
8 11 .14± 0.13 94 ± 10 7.8 ±0.8
( FWHM ~ 0.8 MeV )
Comparison with old data
MeV
Differential cross section of 10B(γ*,K+)10
ΛBe
Peak -B [MeV] Number of event
Cross section [nb/sr]
1 -8.66 ± 0.08 141±12 11.6 ±0.9
2 -7.81 ± 0.23 51±7 4.3 ±0.7
3 -6.08 ± 0.09 139±12 11.8 ±1.0
4 -5.03 ± 0.14 78±9 6.5 ±0.7
5 -1.98 ± 0.10 156±13 13.0 ±0.9
6 -0.11 ± 0.16 123±11 10.0 ±0.8
7 2.23 ± 0.07 188±14 15.9 ±1.1
8 11 .14± 0.13 94 ± 10 7.8 ±0.8
( FWHM ~ 0.8 MeV )
-8.84 without CSB-8.76 with CSBHiyama’s calc.
Motoba’s calc.
9Be(γ*,K+)9ΛLi (only figure)
Summary
• Estimated missing mass resolution• Blind analysis• Resolution and linearity balance• Response function
• Missing mass status• Binding energy and cross section• 12
ΛB, 10ΛBe and 7
ΛHe
Backup
Expected achievable missing mass resolution•分解能の表• 各寄与• Z-depenenceを引いた後に残る分解能
Tuningで z-dependenceを吸収 Resolution ? Linearity?
Blind analysis (next)