multijet production in neutral current dis and the ... · roman kogler on behalf of the h1...
TRANSCRIPT
Roman Kogleron behalf of the H1 collaboration
1
Multijet Production In Neutral Current DIS
And The Determination Of αs
DIS2011 Newport News, April 12, 2011
Roman Kogler Jets At High Q2 and Determination of αs
Jet Production in Leading Order
Only hard QCD processes generate considerable PT in the Breit framen-jet production in LO ∝ αsn-1
Q2
e
q
e'
p
xBj·P
q
g!·P
q
q
!·P
Boost to Breit frame,PT
only EW coupling
2xP + q = 0
∝αs
Momentum fraction of struck parton (in LO):
∝αs
! = x
!1 +
M212
Q2
"
2Roman Kogler Jets At High Q2 and Determination of αs
Multijet Measurement
Neutral current phase space:
150 < Q2 < 15 000 GeV2
0.2 < y < 0.7
Common Jet Phase Space:
-1.0 < ηlab < 2.5
Inclusive Jets:
7 < PT < 50 GeV
Dijets and Trijets:
5 < PT < 50 GeVM12 > 16 GeV
3Roman Kogler Jets At High Q2 and Determination of αs
H1
scattered electron
ep
jet
jet
Q2
yηlab
PT
M12
... virtuality of exchanged boson
... inelasticity
... jet pseudorapidity in lab frame
... jet transverse momentum in Breit frame... invariant mass of two leading jets
inclusive kT algorithm with R0 = 1
Jet and Event Reconstruction
4Roman Kogler Jets At High Q2 and Determination of αs
Energy flow algorithm: combines information from tracks and calorimeter clusters
Neural networks employed to separateelectromagnetic from hadronic showers in the LAr calorimeter
Electromagnetic probability derived from neural network output
Final reconstruction and analysis softwareImprovements in many aspects:
• Track and vertex finding• Scattered electron: energy and polar angle measurement• Reconstruction of the hadronic final state
The Hadronic Final State (HFS):
Network output−1 −0.8−0.6−0.4−0.2 0 0.2 0.4 0.6 0.8 1
even
ts210
310
410±π
0π, γ
Jet Energy Scale Uncertainty
5Roman Kogler Jets At High Q2 and Determination of αs
>da T
/ P
h T<
P
0.95
1
1.05
Calibration Sample
H1 Preliminary
DataDjangohRapgap
[GeV]jetE20 30 40 100 200
Data
/ M
C0.98
11.02 Data/Djangoh Data/Rapgap
Overconstrained kinematics allow calibration of jets in dedicated sample
Calibration takes the probability of clusters to originate from electromagnetic showers into account
Jet Energy Scale uncertainty of 1% over a large range in pseudorapidity
Improved resolutions
electron
jet
Jet Measurement
6Roman Kogler Jets At High Q2 and Determination of αs3
10
×En
tries
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10
2103 1
0×
Entri
es
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210 H1 Preliminary2 < 15000 GeV2400 < Q
[GeV]TP6 7 8 10 20 30 40 100
Ratio
0.5
1
1.5
3 1
0×
Entri
es
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3 1
0×
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es
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210H1 Preliminary
2 < 400 GeV2150 < QH1 Incl. JetDjangoh (rew.)Rapgap (rew.)Background
[GeV]TP6 7 8 10 20 30 40 100
Ratio
0.5
1
1.5 Data/Djangoh Data/Rapgap
Full Hera-2 dataset with L ≈ 350 pb-1
Background between 1.1 and 0.4%
MCs were reweighted to improve the description of the data → reliable detector correction
Measurement of single and double-differential cross sections as function of Q2, PT and ξ
Main experimental uncertainties:
acceptance correction → Δσ/σ = 1.5-8%
jet energy scale 1% → Δσ/σ = 2-5%
luminosity measurement → Δσ/σ = 2.5%
Multijet Cross Sections
7Roman Kogler Jets At High Q2 and Determination of αs
NLO calculations: NLOJet++ using HERAPDF1.5
NLO corrected for hadronisation and effects from Z0 exchange
Data: corrected for detector effects and QED radiation
αs(MZ)=0.118, µr = µf =!"
Q2 + P 2T
#/2
Theoretical uncertainty estimated by variation of μr and μf by a factor of 2
Hadronisation correction 0.94-0.98 (0.8-0.9 for trijet)
H1 Preliminary
]-1 [p
b G
eVT
/dP
jet
σd 1
10
210
]-1 [p
b G
eVT
/dP
jet
σd 1
10
210Inclusive Jet H1 Data (prel.)
0 Z⊗ h c⊗NLO HERAPDF 1.5
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2H1 Preliminary H1 Preliminary
]-1>
[pb
GeV
T/d
<Pdi
jet
σd -110
1
10
210
]-1>
[pb
GeV
T/d
<Pdi
jet
σd -110
1
10
210 Dijet H1 Data (prel.)0 Z⊗ h c⊗NLO
HERAPDF 1.5
> [GeV]T<P8 9 10 20 30 40
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20 30 40
Ratio
0.81
1.2H1 Preliminary H1 Preliminary
]-1>
[pb
GeV
T/d
<Ptri
jet
σd -110
1
10
]-1>
[pb
GeV
T/d
<Ptri
jet
σd -110
1
10
Trijet H1 Data (prel.)0 Z⊗ h c⊗NLO
HERAPDF 1.5
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2H1 Preliminary
Inclusive Jet Cross Sections
8Roman Kogler Jets At High Q2 and Determination of αs
H1 Preliminary
Inclusive Jet Cross Section
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
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-110
1 ]-3
[pb
GeV
TdP2
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2σd
-310
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1 2 < 200 GeV2150 < QH1 Data (prel.)
0 Z⊗ h c⊗NLO
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
]-3
[pb
GeV
TdP2
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2σd
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2 < 270 GeV2200 < Q
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
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-110
]-3 [p
b G
eVT
dP2/d
Q2
σd
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[pb
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TdP2
/dQ
2σd -410
-310
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-110 ]-3 [p
b G
eVT
dP2/d
Q2
σd -410
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-110 2 < 700 GeV2400 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd -510
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-310
]-3
[pb
GeV
TdP2
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2σd -510
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2 < 5000 GeV2700 < Q
]-3
[pb
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TdP2
/dQ
2σd
-610
-510
-410
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
-510
-410 2 < 15000 GeV25000 < Q
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
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[GeV]TP8 9 10 20 30 40
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0.81
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[GeV]TP8 9 10 20 30 40
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0.81
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0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
H1 Preliminary
Inclusive Jet Cross Section
H1 Preliminary
Inclusive Jet Cross Section
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
1 ]-3
[pb
GeV
TdP2
/dQ
2σd
-310
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-110
1 2 < 200 GeV2150 < QH1 Data (prel.)
0 Z⊗ h c⊗NLO
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
]-3
[pb
GeV
TdP2
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2σd
-310
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2 < 270 GeV2200 < Q
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
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-110
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
-1102 < 400 GeV2270 < Q ]-3
[pb
GeV
TdP2
/dQ
2σd -410
-310
-210
-110 ]-3 [p
b G
eVT
dP2/d
Q2
σd -410
-310
-210
-110 2 < 700 GeV2400 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd -510
-410
-310
]-3
[pb
GeV
TdP2
/dQ
2σd -510
-410
-310
2 < 5000 GeV2700 < Q
]-3
[pb
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TdP2
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-610
-510
-410
]-3
[pb
GeV
TdP2
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-610
-510
-410 2 < 15000 GeV25000 < Q
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
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0.81
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[GeV]TP8 9 10 20 30 40
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0.81
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0.81
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[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
H1 Preliminary
Inclusive Jet Cross Section
H1 Preliminary
Inclusive Jet Cross Section
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
1 ]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
1 2 < 200 GeV2150 < QH1 Data (prel.)
0 Z⊗ h c⊗NLO
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
2 < 270 GeV2200 < Q
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
-110
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
-1102 < 400 GeV2270 < Q ]-3
[pb
GeV
TdP2
/dQ
2σd -410
-310
-210
-110 ]-3 [p
b G
eVT
dP2/d
Q2
σd -410
-310
-210
-110 2 < 700 GeV2400 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd -510
-410
-310 ]
-3 [p
b G
eVT
dP2/d
Q2
σd -510
-410
-310
2 < 5000 GeV2700 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
-510
-410
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
-510
-410 2 < 15000 GeV25000 < Q
[GeV]TP8 9 10 20 30 40
Ratio
0.81
1.2
[GeV]TP8 9 10 20 30 40
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0.81
1.2
[GeV]TP8 9 10 20 30 40
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0.81
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[GeV]TP8 9 10 20 30 40
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0.81
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0.81
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0.81
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Ratio
0.81
1.2
H1 Preliminary
Inclusive Jet Cross Section
Data are well described by NLO calculations over large range in Q2 and PT
Experimental uncertainty of 4-8% about half the theoretical uncertainty
H1 Preliminary
Inclusive Jet Cross Section ]
-3 [p
b G
eVT
dP2/d
Q2
σd -310
-210
-110
1 ]
-3 [p
b G
eVT
dP2/d
Q2
σd -310
-210
-110
12 < 200 GeV2150 < Q
H1 Data (prel.)0 Z⊗ h c⊗NLO
HERAPDF 1.5
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
1 ]-3
[pb
GeV
TdP2
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2σd
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1 2 < 270 GeV2200 < Q ]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
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-110
2 < 400 GeV2270 < Q ]-3 [p
b G
eVT
dP2/d
Q2
σd -410
-310
-210
-110 ]-3
[pb
GeV
TdP2
/dQ
2σd -410
-310
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]-3
[pb
GeV
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/dQ
2σd -510
-410
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-210 ]-3
[pb
GeV
TdP2
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2σd -510
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-210 2 < 5000 GeV2700 < Q
]-3
[pb
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]-3
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[GeV]TP8 9 10 20 30 40
Ratio
0.81
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0.81
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H1 Preliminary
Inclusive Jet Cross Section
Comparison With Different PDFs
9Roman Kogler Jets At High Q2 and Determination of αs
[GeV]TP
NLO
/ Da
ta
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
10
bin 12Q
10
bin 22Q
10
bin 32Q
10
bin 42Q
10
bin 52Q
10
bin 62Q
) = 0.1180Z
(MsαHERAPDF 1.5 with NLO unc.NNPDF 2.0CT10
H1 PreliminaryInclusive Jet
Differences small in most regions of phase space, visible differences at high PT
Central predictions for different PDFs shown
Different x regions of gluon and valence distributions probed in different regions of Q2 and PT
Trijet Cross Sections
10Roman Kogler Jets At High Q2 and Determination of αs
H1 Preliminary
Trijet Cross Section ]
-3 [p
b G
eVT
dP2/d
Q2
σd
-310
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[pb
GeV
TdP2
/dQ
2σd
-310
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-110 2 < 200 GeV2150 < QH1 Data (prel.)
0 Z⊗ h c⊗NLO
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/dQ
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-310
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]-3
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b G
eVT
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Q2
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0.81
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H1 Preliminary
Trijet Cross Section
H1 Preliminary
Trijet Cross Section
]-3
[pb
GeV
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-310
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[pb
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TdP2
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0 Z⊗ h c⊗NLO
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> [GeV]T<P8 9 10 20
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H1 Preliminary
Trijet Cross Section
H1 Preliminary
Trijet Cross Section
]-3
[pb
GeV
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[pb
GeV
TdP2
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2σd
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0 Z⊗ h c⊗NLO
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]-3
[pb
GeV
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2 < 270 GeV2200 < Q
]-3 [p
b G
eVT
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Q2
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eVT
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]-3 [p
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H1 Preliminary
Trijet Cross Section
H1 Preliminary
Trijet Cross Section
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110 ]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
-110 2 < 200 GeV2150 < QH1 Data (prel.)
0 Z⊗ h c⊗NLO
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
2 < 270 GeV2200 < Q
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-2102 < 400 GeV2270 < Q ]-3
[pb
GeV
TdP2
/dQ
2σd
-410
-310
]-3 [p
b G
eVT
dP2/d
Q2
σd
-410
-310
2 < 700 GeV2400 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd
-510
-410 ]
-3 [p
b G
eVT
dP2/d
Q2
σd
-510
-410
2 < 5000 GeV2700 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
2 < 15000 GeV25000 < Q
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
H1 Preliminary
Trijet Cross Section
First double-differential trijet cross section measurement at high Q2
Experimental uncertainty of 6% (low <PT>) and 15% (high <PT>)
H1 Preliminary
Trijet Cross Section ]
-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
-110 ]
-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
-1102 < 200 GeV2150 < Q
H1 Data (prel.)0 Z⊗ h c⊗NLO
HERAPDF 1.5
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
2 < 270 GeV2200 < Q ]-3
[pb
GeV
TdP2
/dQ
2σd
-310
-210
]-3 [p
b G
eVT
dP2/d
Q2
σd
-310
-210
2 < 400 GeV2270 < Q ]-3 [p
b G
eVT
dP2/d
Q2
σd
-410
-310
-210
]-3 [p
b G
eVT
dP2/d
Q2
σd
-410
-310
-210 2 < 700 GeV2400 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd -510
-410
-310 ]-3
[pb
GeV
TdP2
/dQ
2σd -510
-410
-310 2 < 5000 GeV2700 < Q
]-3
[pb
GeV
TdP2
/dQ
2σd
-610
-510 ]-3
[pb
GeV
TdP2
/dQ
2σd
-610
-510 2 < 15000 GeV25000 < Q
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
> [GeV]T<P8 9 10 20
Ratio
0.81
1.2
H1 Preliminary
Trijet Cross Section
Determination of αs(MZ)NLO calculation depends on PDF and
Keep PDF (CT10) fixed and fit ⇒⇒ Assign an error due to PDF uncertainty
Hessian method: Minimise !2("s)
!s(MZ)
!s(MZ)
11Roman Kogler Jets At High Q2 and Determination of αs
αs
di ... measured cross section in bin i
ti ... theoretical prediction for bin i obtained with FastNLO (based on NLOJet++)
σi,stat ... statistical uncertainty in bin i
σi,uncorr ... uncorrelated systematic uncertainty in bin i
Δik ... effect of correlated systematic uncertainty k in bin i
εk ... free variables of the fit, one for each correlated uncertainty
!2 =N!
i=1
[di ! ti(1!"
k "k!ik)]2
#2i,stat + #2
i,uncorr
+!
k
"2k
Statistical correlations taken into account in case of inclusive jet cross sections
αs(MZ) From Multijet Cross Sections
12Roman Kogler Jets At High Q2 and Determination of αs
Inclusive Jet:
Dijet:
Trijet:
Theoretical uncertainty dominates for all observables, determined from scale variations: μr and μf varied by a factor of 2
αs from trijet cross sections: most precise experimental result, smallest PDF uncertainty
!s(MZ) = 0.1190 ± 0.0021 (exp.) ± 0.0020 (pdf) +0.0050!0.0056 (th.)
!s(MZ) = 0.1146 ± 0.0022 (exp.) ± 0.0021 (pdf) +0.0044!0.0045 (th.)
!s(MZ) = 0.1196 ± 0.0016 (exp.) ± 0.0010 (pdf) +0.0055!0.0039 (th.)
αs(MZ) From Trijet Cross Sections
13Roman Kogler Jets At High Q2 and Determination of αs
> [GeV]T<P
) Z(M s
α
0.08
0.09
0.1
0.11
0.12
0.13
0.14
0.15
0.16
> [GeV]T<P
) Z(M s
α
0.08
0.09
0.1
0.11
0.12
0.13
0.14
0.15
0.16
10
bin 12Q
10
bin 22Q
10
bin 32Q
10
bin 42Q
10
bin 52Q
10
bin 62Q
0.0016 (exp)±) = 0.1196 Z
(Msα
individual fit
Trijet
H1 PreliminaryIndividual fits performed to all data points
Grey band shows the experimental uncertainty of the simultaneous fit
Error bars of individual fit from uncorrelated uncertainties only
PDF, hadronisation uncertainty and uncertainty from terms beyond NLO not shown
αs(MZ) From Different Jet Multiplicities
14Roman Kogler Jets At High Q2 and Determination of αs
αs(MZ) values from inclusive jet, dijet and trijet measurements by H1
Experimental uncertainties always smaller than uncertainties due to terms beyond NLO
Dijet data give smaller values of αs(MZ), within theoretical uncertainty
)Z
(Msα0.11 0.12 0.13
)Z
(Msα0.11 0.12 0.13
uncertaintyexp.th.
World averageS. Bethke, Eur. Phys. J. C64, 689 (2009)
trijet2H1 low QEur. Phys. J. C67, 1 (2010)
norm. trijet2H1 high QEur. Phys. J. C65, 363 (2010)
trijet2H1 high QH1−prelim−11−032
dijet2H1 low QEur. Phys. J. C67, 1 (2010)
norm. dijet2H1 high QEur. Phys. J. C65, 363 (2010)
dijet2H1 high QH1−prelim−11−032
inclusive jet2H1 high QPhys. Lett. B653, 134 (2007)
inclusive jet2H1 low QEur. Phys. J. C67, 1 (2010)
norm. inclusive jet2H1 high QEur. Phys. J. C65, 363 (2010)
inclusive jet2H1 high QH1−prelim−11−032
new
new
new
Comparison With Recent Results
15Roman Kogler Jets At High Q2 and αs Fits
)Z
(Msα0.11 0.12 0.13
)Z
(Msα0.11 0.12 0.13
uncertaintyexp.th.
World averageS. Bethke, Eur. Phys. J. C64, 689 (2009)
D0 incl. midpoint cone jetsPhys. Rev. D80, 111107 (2009)
Aleph Event Shapes, NNLO+NLLAJHEP 08, 036 (2009)
Aleph 3−jet rate, NNLOPhys. Rev. Lett. 104, 072002 (2010)
jets, NLOTZEUS incl. anti−kPhys. Lett. B691, 127 (2010)
jets, NLOTZEUS incl. kPhys. Lett. B 649, 12 (2007)
multijets, NLOT k2H1 low QEur. Phys. J. C67, 1 (2010)
multijets, NLOT norm. k2H1 high QEur. Phys. J. C65, 363 (2010)
H1+ZEUS NC, CC and jet QCD fits, NLOH1−prelim−11−034
trijet, NLO2H1 high QH1−prelim−11−032
dijet, NLO2H1 high QH1−prelim−11−032
inclusive jet, NLO2H1 high QH1−prelim−11−032
new
new
new
Summary
• Stringent test of pQCD
• Tests of available PDFs
• Important for future combined PDF and αs determinations
Extracted values of αs(MZ) competitive with other measurements, dominated by theoretical uncertainties
16Roman Kogler Jets At High Q2 and Determination of αs
Most precise measurement of jet cross sections at e+e-, ep and hadron colliders (together with ZEUS dijets at high Q2)
Inclusive jet, dijet and trijet cross sections at high Q2 measured single and double differentially
Trijet cross sections give smallest PDF and experimental uncertainties on αs(MZ)
Looking forward to eventual NNLO calculations or resummation corrections as calculated for the Tevatron
αs(MZ) From Multijet Cross Sections
17Roman Kogler Jets At High Q2 and Determination of αs
Inclusive Jet:
Dijet:
Trijet:
!s(MZ) = 0.1190 ± 0.0021 (exp.) ± 0.0020 (pdf) +0.0050!0.0056 (th.)
!s(MZ) = 0.1146 ± 0.0022 (exp.) ± 0.0021 (pdf) +0.0044!0.0045 (th.)
!s(MZ) = 0.1196 ± 0.0016 (exp.) ± 0.0010 (pdf) +0.0055!0.0039 (th.)
Norm. Inclusive Jet (Eur. Phys. J C65, 363):
!s(MZ) = 0.1195 ± 0.0010 (exp.) ± 0.0018 (pdf) +0.0049!0.0036 (th.)
Norm. Dijet (Eur. Phys. J C65, 363):
!s(MZ) = 0.1155 ± 0.0009 (exp.) ± 0.0017 (pdf) +0.0042!0.0031 (th.)
Norm. Trijet (Eur. Phys. J C65, 363):
!s(MZ) = 0.1172 ± 0.0013 (exp.) ± 0.0009 (pdf) +0.0052!0.0031 (th.)