qcd and b and charm physics at the tevatron and b and charm physics at the tevatron stephen wolbers,...
TRANSCRIPT
QCD and B and charm Physics at the Tevatron
Stephen Wolbers, Fermilab On behalf of the CDF and DØ Collaborations
PLHC 2012, Vancouver June 6, 2012
Overview
• Introduction • Recent QCD results
– Inclusive jets (DØ) – γ+b, γ+c jets (DØ, CDF)
• Heavy quark (b and c) physics – Fragmentation (CDF) – CP asymmetries in B and D physics (CDF) – Rare decays and new states (DØ, CDF) – Lifetimes (DØ)
• Summary
PLHC 2012 Stephen Wolbers 2
Tevatron Collider • The Tevatron Collider ran
from 1985 to 2011 (with intervals of fixed-target running and upgrades)
• Run 2 covers the years from 2001 to 2011
• In Run 2 proton-antiproton collisions occurred at center of mass energy 1.96 TeV
• ≈10 fb-1 luminosity was recorded for each experiment
• This is a large and well-understood dataset
PLHC 2012 Stephen Wolbers 3
CDF and DØ Experiments • The focus today will be on recent
CDF and DØ measurements that satisfy one or more of the following: – Use the entire ~10 fb-1 dataset – Update previous results – Are significant new results in the
areas of QCD or B and charm physics
• Take advantage of: – The p-pbar initial state – Higher luminosity and statistics – Specialized triggers – New analysis techniques – Improved understanding of the
detectors and errors PLHC 2012 Stephen Wolbers 4
CDF
DØ
QCD
• The QCD analyses are primarily concerned with: – Parton Distribution Functions (pdfs) – Tests of QCD calculations (LO, NLO, NNLO, etc.) – Higher precision and new kinematic regions – Rarer processes only accessible now with larger datasets – Processes where p-pbar allow for interesting and
potentially unique measurements – Many of the QCD analysis involve heavy quarks, and some
of the heavy quark analyses have natural connections to QCD and fragmentation.
PLHC 2012 Stephen Wolbers 6
QCD Inclusive Jets • Inclusive jets with:
• Probe of parton distributions and qq, qg and gg subprocesses in collisions. – Contributions depend on the pT of
the jets (xT of partons) – Measurements are sensitive to
high x gluon distributions • Agreement with CTEQ6.5M and
MRST2004 pdf’s is seen. • PRD 85, 052006 (2012)
PLHC 2012 Stephen Wolbers 7
(GeV)T
p50 60 100 200 300 400
dy(p
b/G
eV)
T/d
p!2 d
-610
-510
-410
-310
-210
-110
110
210
310
410
510
610
710 |y|<0.4 (x32)0.4<|y|<0.8 (x16)0.8<|y|<1.2 (x8)1.2<|y|<1.6 (x4)1.6<|y|<2.0 (x2)2.0<|y|<2.4
s = 1.96 TeV= 0.7coneR
NLO pQCD+non-perturbative corrections
CTEQ6.5M
600
DØ, 0.70 fb-1
!"#" $ #"%&
0
0.2
0.4
0.6
0.8
1
pT (GeV)
Frac
tiona
lcon
tribu
tions
xT = 2pT/sqrt(s)0.05 0.1 0.2 0.4
50 100 200 400
gg ! jets
qq ! jets
gq ! jets
Inclusive jets: Tevatron Run II|y|<0.4
−2.4 < η < 2.4, 50 GeV< pT < 600 GeV
ppDØ
γ + b jets • DØ analysis uses 8.7 fb-1 • Contributions from Qg->γQ
(Compton) and qqbar->γQQbar (annihilation) Probe of quark and gluon
distributions in the proton • Select central (|y|<1.0) and
forward (1.5<|y|<2.5) photons. • The differential cross section
is measured as a function of photon pT
• NLO QCD predictions show good agreement with data up to pT < 70 GeV. Higher order QCD corrections are required at higher pT
PLHC 2012 Stephen Wolbers 8
(GeV)T
p0 50 100 150 200 250 300
(pb/
GeV
)T
/dp
d
-410
-310
-210
-110
1
| < 1.0data, |y| < 2.5data, 1.5 < |y
NLO (Stavreva, Owens) fact. (Lipatov, Zotov)Tk
SHERPA, v1.3.1PYTHIA, v6.420
>15 GeVjetT
|<1.5, pjet|y
(x0.3)
-1DØ, L = 8.7 fb
DØ
γ + b jets, γ + c jets
Luminosity 9.1 fb-1
Fits to b, c, light quark jet fractions are made using templates from MC simulation. Cross sections for γ+b and γ+c events are measured, taking into account efficiencies, unfolding, and other effects.
PLHC 2012 Stephen Wolbers 9
30 < EγT < 300, |yγ | < 1.0
EjetT > 20, |yjet| < 1.5
(GeV)SecVtxM0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Even
ts/0
.2
0123456789
310×
(GeV)SecVtxM0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Even
ts/0
.2
0123456789
310× <50 GeVT40<E
-1CDF data, L=9.1 fblight jetsc jetsb jetsfake photon + jets
CDF Run II Preliminary
CDF
γ + b jets, γ + c jets
The NLO calculations match the data at low ET, but fall below the data at high ET, showing the need for higher order terms. - Similar conclusion to the DØ results in γ+b jets. - CDF Public Note 10818 PLHC 2012 Stephen Wolbers 10
(GeV)TE50 100 150 200 250 300
(pb/
GeV
)T
/dE
d
-310
-210
-110
1
10-1+jets data, L=9.1 fbCDF
+c+XSystematic uncertaintyNLO (Stavreva, Owens)PYTHIAPYTHIA, mstj(42)=4, mstj(44)=3
CDF Run II Preliminary
(GeV)TE50 100 150 200 250 300
(pb/
GeV
)T
/dE
d
-310
-210
-110
1
10
(GeV)TE50 100 150 200 250 300
(pb/
GeV
)T
/dE
d
-310
-210
-110
1-1+jets data, L=9.1 fbCDF
+b+XSystematic uncertaintyNLO (Stavreva, Owens)PYTHIAPYTHIA, mstj(42)=4, mstj(44)=3
CDF Run II Preliminary
(GeV)TE50 100 150 200 250 300
(pb/
GeV
)T
/dE
d
-310
-210
-110
1
CDF CDF γ+b jets γ+c jets
Heavy Quark Physics
• Heavy Quark Physics – The study of heavy quark physics in p-pbar collisions
provides valuable insight to HEP. – In particular, beyond standard model physics at higher
energy scales can be accessed using low-energy, well-predicted flavor observables.
– This talk will cover just a few results in the areas of: • Fragmentation • CP asymmetry • Decay modes • Lifetimes
PLHC 2012 Stephen Wolbers 12
Quark fragmentation using K in association with Ds
+ /D+
• A study of fragmentation looking at the charged K of same and opposite sign associated with D+ and Ds
+ – Expect to see differences in
rates of opposite-sign and same-sign K
• ~260,000 Ds+ and 140,000 D+
decaying to KKπ. The impact parameter distribution was used to separate prompt Ds
+/D+ from Ds+/D+
from B decays. • The results show expected
qualitative behavior of opposite and like-sign K rates as a function of K pT.
PLHC 2012 Stephen Wolbers 13
-1CDF Run II preliminary - 360 pb
)2) (GeV/c+-K+m(K1.8 1.9 2 2.1 2.2
2En
tries
per
2 M
eV/c
0
10
20
30
40
50310×
+ s+D
+ +D+-+ K+D
background
CDF
Quark fragmentation using K in association with Ds
+/D+ Big difference between Ds (left) and D (right) in opposite sign K production.
Agrees with models
Ds and D similar in same sign K production
Disagrees with fragmention models
Valuable input for further tuning of models.
PLHC 2012 Stephen Wolbers 14
(GeV/c)T
p0 1 2 3 4 5 6 7
Kaon
frac
tion
0
0.2
0.4
0.6
0.8
1DataPYTHIAHERWIG
Opposite sign±sPrompt D
(GeV/c)T
p0 1 2 3 4 5 6 7
Kaon
frac
tion
0
0.2
0.4
0.6
0.8
1
DataPYTHIAHERWIG
Opposite sign±Prompt D
(GeV/c)T
p0 1 2 3 4 5 6 7
Kaon
frac
tion
0
0.2
0.4
0.6
0.8
1DataPYTHIAHERWIG
Same sign±sPrompt D
(GeV/c)T
p0 1 2 3 4 5 6 7
Kaon
frac
tion
0
0.2
0.4
0.6
0.8
1
DataPYTHIAHERWIG
Same sign±Prompt D
D Ds CDF
Ds D
CDF Public Note 10704
CDF Run II Preliminary – 360 pb-1
CP Asymmetry in Heavy Quark Decay: ΔAcp(D0->hh)
• CDF measured Acp(D0->KK) and ACP(D0->ππ), as well as the difference in the two quantities, ΔAcp(D0->hh) in 5.9 fb-1 – Acp(D0->KK) = [−0.24 ± 0.22(stat) ± 0.10(sys)]% – ACP(D0->ππ) = [0.22 ± 0.24(stat) ± 0.11(sys)]% – ΔAcp(D0->hh) = [-0.46 ± 0.31(stat) ± 0.12(sys)]% (PRD 85, 012009 (2012))
• The analysis for ΔAcp has been updated with the full Run 2 dataset
• The event selection is relaxed due to cancellation of systematics in the difference measurement, leading to more signal events
• D0 flavor is determined by the D*->D0πs decay • Detector effects are canceled by using the difference of raw
asymmetries of the KK and ππ decays: ΔAcp = A(KK*)-A(ππ*) = Acp(K+K-)-Acp(π+π-) PLHC 2012 Stephen Wolbers 15
ΔAcp(D0->hh)
• ~550K D* tagged D0->π+π- • ~1.21M D* tagged D0->K+K- • Fits were used to extract
the signal, BG, and multibody decays.
• A(ππ*) = (-1.71±0.15)% • A(KK*) = (-2.33±0.14)%
– (Raw quantities) ΔACP=[-0.62±0.21 ±0.10]% 2.7σ different from 0 CDF public note 10784 This result is a confirmation of LHCb measurement: ΔAcp=[-0.83±0.21±0.11]%
PLHC 2012 Stephen Wolbers 16
5
10
15
20
310×+s) -+ (0 D +D* -
s) -+ (0
D -D*
)-1Data (9.7 fbFit
D decaysMultibody
Random pions
CDF Run II Preliminary
2.005 2.01 2.0150
10
20
30
40
50 +s) -K+ K (0 D +D*
2.005 2.01 2.015 2.02
-s) -K+ K (
0D -D*
]2-mass [GeV/cs0Invariant D
2C
andi
date
s pe
r 0.1
MeV
/c
CDF
Acp in D0->Ksππ
• Acp is also measured in CDF in D0 decay to Ksππ – Standard Model
expectations ~10-6 • D* tag is used to
determine D0 flavor • Two methods are used:
– A full Dalitz fit using the isobar model
– A model independent bin-by-bin comparison of D0 and D0-bar plots.
• From the fits Acp is extracted
PLHC 2012 Stephen Wolbers 17
]2) [GeV/c-+0sMass(K
1.8 1.82 1.84 1.86 1.88 1.9 1.92 1.94 1.96 1.98 2
2C
andi
date
s pe
r 1.0
MeV
/c
0
2000
4000
6000
8000
10000
12000
14000
16000
-1CDF Run II preliminary, L = 6.0 fb
353000S 37000B
]2) [MeV/c-+0s)-Mass(K+ -+0
sMass(K140 142 144 146 148 150 152 154 156
2C
andi
date
s pe
r 0.1
MeV
/c
02000400060008000
1000012000140001600018000200002200024000 352000S
38000B
-1CDF Run II preliminary, L = 6.0 fb
CDF
Acp in D0->K0ππ
• Resonance substructure (amplitude and phases) are measured – No evidence for CP violation is
found in any sub resonance, with resolutions better than previous experiments.
• A model-independent difference bin-by-bin subtraction is also measured
• Integrating over all modes: • Acp = -0.0005 ± 0.0057 ± 0.0054 Assuming no direct CP asymmetry one can derive: • Acp
ind = -0.0002+-0.0025+-0.0024
PLHC 2012 Stephen Wolbers 18
-5
-4
-3
-2
-1
0
1
2
3
4
5
]4/c2 [GeV2(RS)±0
sKM0 0.5 1 1.5 2 2.5 3
]4/c2
[GeV
2-
+M
00.20.40.60.8
11.21.41.61.8
2-1CDF Run II preliminary, L = 6.0 fb
= 49172
NDF = 5092prob = 0.96
B->µ+µ-
• Processes involving FCNC are an excellent way to search for new physics
• SM predictions: BR(Bs->µ+µ-) = (3.2±0.2)x10-9, BR(Bd->µ+µ-) = (1.0±0.1)x10-10
• CDF published results using 7 fb-1 (PRL 107, 191801 (2011)) – BR(Bd->µ+µ-) < 6.0 × 10-9 at 95% C.L. – BR(Bs->µ+µ-) = 1.8+1.1
-0.9 × 10-8 • The CDF analysis was extended to full Run 2 dataset (9.7 fb-1)
– No change to analysis methods – NN to discriminate signal from background – Normalize to BR(B+->J/ψ K+):
PLHC 2012 Stephen Wolbers 19
]2Invariant Mass [GeV/c5.15 5.2 5.25 5.3 5.35 5.4
2C
andi
date
s pe
r 5 M
eV/c
0
2000
4000
6000
8000
10000
-1CDF II Preliminary 9.7 fb
CC+CF
267±) = 40225 ±N(B(B)>4 GeV/c
Tp
NN Output0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Can
dida
tes
per 0
.01
-310
-210
-110
1
CC+CF sidebandCC+CF signal MC
-1CDF II Preliminary 9.7 fb
2>5.0GeV/c-µ+µsideband: M
B->µ+µ-
• The challenge is to reject a large background while keeping most of the signal
• 14 discriminating variables were used to build an optimized neural net classifier to separate signal from background
• Combinatorial background is estimated from mass sidebands • Fake muon background estimated from B->hh and D->Kπ
PLHC 2012 Stephen Wolbers 20
0
10
20
30
< 0.76N0.70 < < 0.85N0.76 < < 0.90N0.85 < < 0.94N0.90 <
-µ+µ0sB
)2 (MeV/cµµm
0
5
10
15
5322 5370 5418 5322 5370 5418 5322 5370 5418 5322 5370 5418
< 0.97N0.94 < < 0.987N0.97 < < 0.995N0.987 < > 0.995N
Background
4.1)×+Signal (SM
2C
andi
date
s pe
r 24
MeV
/c
0
CDF Preliminary 9.7 fb-1 CDF
• Results: BR(Bd→µ+µ-) < 4.6 × 10-9 (95% CL) BR(Bs → µ+µ-)=(1.3+0.9
-0.7)× 10-8
0.8 × 10-9 < BR(Bs-> µ+µ-) < 3.4 × 10-8
(95% CL) BR(Bs → µ+µ-) < 3.1 × 10-8 (2.7× 10-8) 95% (90%) CL CDF publication is in preparation Getting closer to a measurement of the Bs->µµ
Bs->µ+µ-
PLHC 2012 Stephen Wolbers 21
@ 95% CL9 10×)-µ+µsBF(B0 20 40
-1D0 6 fbPLB 693 (2010) 539
-1CDF 7 fbPRL 107 (2011) 191801
-1CDF 10 fbwww-cdf.fnal.gov/physics/new/bottom/120209.bmumu10fb/
-1LHCb 1 fbLHCb-PAPER-2012-007
-1CMS 4.9 fbCMS PAS BPH-11-020
-1ATLAS 2.4 fbATLAS-CONF-2012-010
SM Prediction(68% CL region)
March 2012
• Using the full Run 2 dataset CDF measures the ratio: – R= (fs * BR(Bs->J/ψ ϕ)/ fd * BR(B0->J/ψ K*))
• Selection is optimized by maximizing S/√S+B.
• A binned log likelihood fit is made to signal shape templates and background functions: ~11,000 J/ψϕ ~57,000 J/ψK*
• Final result, corrected for acceptance: – R = 0.239±0.003±0.019
• Using CDF fs/fd and PDG BR(B0->JψK*) we can extract: – BR(Bs->J/ψϕ) =
(1.18±0.02±0.09±0.014±0.05)*10-3
– World’s best measurement. PLHC 2012 Stephen Wolbers 22
BR(Bs → J/ψφ) and fs/fd
)2 invariant mass (GeV/c J/5.25 5.3 5.35 5.4 5.45 5.5 5.55 5.6 5.65 5.7
2ca
ndid
ates
per
3 M
eV/c
200
400
600
800
1000
1200
1400
1600
1800
-1CDF Run II Preliminary, 9.6 fb
)2 invariant mass (GeV/c J/5.25 5.3 5.35 5.4 5.45 5.5 5.55 5.6 5.65 5.7
2ca
ndid
ates
per
3 M
eV/c
200
400
600
800
1000
1200
1400
1600
1800DataTotal Fit
Signal J/ sB K* Bkg. J/ 0B
Bkg.0 f J/ sBComb. Bkg.
)2invariant mass (GeV/c* KJ/5.1 5.15 5.2 5.25 5.3 5.35 5.4 5.45 5.5 5.55 5.6
2ca
ndid
ates
per
3 M
eV/c
1000
2000
3000
4000
5000
6000
7000-1CDF Run II Preliminary, 9.6 fb
)2invariant mass (GeV/c* KJ/5.1 5.15 5.2 5.25 5.3 5.35 5.4 5.45 5.5 5.55 5.6
2ca
ndid
ates
per
3 M
eV/c
1000
2000
3000
4000
5000
6000
7000DataTotal Fit
Signal* K J/ 0B Bkg.* K J/ sB
Bkg. J/ sB Bkg.0 f J/ sB
Comb. Bkg.Part. Recon. Bkg.
CDF
• The fits to Bs->J/ψϕ and Bs->J/ψK* are performed in 4 pT ranges • fs/fd(pT) can be extracted using Belle’s latest BR(Bs->J/ψϕ) • This is the first measurement of fs/fd as a function of pT
• Averaging over all pT: fs/fd=0.254±0.003±0.020±0.044 • More generally, the CDF measurement of fs/fd is a function of BR
(Bs->J/ψϕ) and is shown below
PLHC 2012 Stephen Wolbers 23
)φ ψ J/→sBR(B0 0.0005 0.001 0.0015 0.002 0.0025 0.003
dfsf
0.1
0.2
0.3
0.4
0.5 CDF II measurement
Uncertainty
)φ ψ J/→sBelle BR(B
d/fsPDG f
-4 10⋅ 0.30) ±)=(3.17 φ ψ J/→s BR(B⋅ dfsf
-1CDF Run II Preliminary, 9.6 fb
(GeV/c)TB p5 10 15 20 25
dfsf
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45Statistic UncertaintySystematic UncertaintyCorrelated Uncertainty
PDG valued /fsf
-1CDF Run II Preliminary, 9.6 fb
BR(Bs → J/ψφ) and fs/fd
CDF
• CDF has measured the BR’s of Bs decays: – (Bs->Ds
+Ds+), (Bs->Ds
*+Ds+), (Bs->Ds
*+Ds*+)
• where: (Ds->ϕπ), (Ds->K*0K) • These measurements may provide information on ΔΓs • A neural net is used to separate signal and background
contributions. • The final sample contains ~750 Bs->Ds
(*)Ds(*) decays
• A simultaneous fit is made to Bs and Bd decays to separate the decay contributions. BR’s were normalized to well-measured Bd -> DsD BR’s. – The fitting procedure accounts for partially reconstructed Ds
* decays in the fit using mass shapes.
PLHC 2012 Stephen Wolbers 24
Bs → D(∗)+s D(∗)−
s
• World’s best measurements of the BR’s. • Published in PRL 108, 201801 May
14,2012 • Br(B0
s→ D+sD-
s) = (0.49 ± 0.06 ± 0.05 ± 0.08)% Br(B0
s→ D*+sD-
s) = (1.13 ± 0.12 ± 0.19 ± 0.09)% Br(B0
s→ D*+sD*-
s) = (1.75 ± 0.19 ± 0.17 ±0.29)% Br(B0
s→ D(*)+sD(*)-
s) = (3.38±0.25±0.30±0.56)%
• Values are lower than but consistent with recent Belle result.
• These provide important constraints for indirect searches for new physics.
PLHC 2012 Stephen Wolbers 25
Bs → D(∗)+s D(∗)−
s
10
20
30
40 )-(-s) D+(+
sD DataFit projectionBackground
-s D+
s D s0B
-s D+*s D s
0B-*s D+*s D s
0B
CDF II Preliminary -16.8 fb
Invariant Mass (GeV/c²)5.0 5.50
20
40
60)-(-
s) D+K0*K(+sD - D+
s D 0B- D*+
s D 0B- D+*s D 0B
- D*+*s D 0B
2C
andi
date
s pe
r 10
MeV
/c
CDF
• This measurement uses the full Run 2 dataset : 10.4 fb-1 • Require a 4 track vertex, where the µ+µ- consistent with J/ψ, and
1.35<M(K+K-)<2.0 GeV • MC templates used to separate contributions from (J/ψ f2’(1525)), (J/
ψ ϕ), (J/ψ K2*(1430)), (J/ψ K0*(1430)) • Fitting is done as a function of K+K- mass to extract the f2(1525)
contribution. Contributions from K0*(1430) and f2’(1525) are seen.
PLHC 2012 Stephen Wolbers 26
B0s → J/ψf �
2(1525)
) (GeV)-K+K-µ+µM(5.2 5.4 5.6 5.8
Even
ts /
28 M
eV
0
500
1000
1500
2000 -1DØ Run II, 10.4 fbData
Full Fit
Signal
K*(892)
Bkg
) (GeV)-K+K-µ+µM(5.2 5.4 5.6 5.8
Even
ts /
20 M
eV
0
200
400
600
800 -1DØ Run II, 10.4 fb (a)DataFull FitSignal
(1430)J*K
Bkg
DØ Final Fit Normalization J/ψϕ
• Spin of K+K- is studied and is consistent with a combination of spin 0 and spin 2 and is inconsistent with spin 1.
• R = BR(Bs->J/ψ f2’(1525))/BR(Bs->J/ψ ϕ) = 0.22±0.05±0.04 – arXiv:1204.5723 (submitted to Phys. Rev. D)
• R(LHCb) = 0.26±0.027±0.024
PLHC 2012 Stephen Wolbers 27
B0s → J/ψf �
2(1525)DØ
||cos 0 0.2 0.4 0.6 0.8 1
Even
ts /0
.2
0
200
400
600 DataJ=2 + J=0J=2J=1J=0
-1DØ Run II, 10.4 fb
) (GeV)-K+M(K1.4 1.6 1.8 2
Even
ts /
50 M
eV
-200
0
200
400
-1DØ Run II, 10.4 fb
ϒ candidates in the mass range 9.1<M<9.7 are combined with photons identified by their conversions into e+e -- pairs. 3 peaks in the mass difference Mµµγ-Mµµ are seen corresponding to χb(1P), χb(2P) and a new state with significance 5.6σ, consistent with a state seen by ATLAS.
M(new state)=10.551±0.014±0.017 arXiv:1203.6034 (Submitted to PRD RC) ATLAS: M=10.530±0.005±0.009 (PRL 108, 152001 (2012))
PLHC 2012 Stephen Wolbers 28
] 2 [GeV/c(1S) + mµµ - MµµM9.5 10 10.5 11 11.5
2Ev
ents
/ 5
0 M
eV/c
0
5
10
15
20
25
30
35
40
45 DataFull fitBkg only
(1P)b(2P)
bNew state
-1DØ, 1.3 fb
χb → Υ(1S) + γ
DØ
Λb Lifetime
• Λb lifetime is a puzzle, measurements don’t agree, deviations from predictions. – New measurements are needed to help resolve the mystery.
• New DØ analysis of the Λb lifetime • Uses full Run 2 Dataset – 10.4 fb-1
• This analysis measures lifetimes in two similar decay modes: – Λb->J/ψΛ, B0->J/ψKs
0 • Separate fits to both Λb and B0 lifetimes in topologically similar
decays
PLHC 2012 Stephen Wolbers 29 ]2c) [GeV/0 /JMass (
5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 6
2 cC
andi
date
s pe
r 18
MeV
/
0
100
200
300
400
500
-1(a) DØ, 10.4 fbDataData fitSignalCombinatorialPartially recon-
hadronsbstructed
J/ψΛ
]2c) [GeV/0SK /JMass (
4.9 5 5.1 5.2 5.3 5.4 5.5 5.6 5.7
2 cC
andi
date
s pe
r 12
MeV
/
0
200
400
600
800
1000
1200
-1(b) DØ, 10.4 fbDataData fitSignalCombinatorialPartially recon-
hadronsbstructed
J/ψKs0 DØ
• Final fit results: – τ(Λb) = 1.303 ± 0.075 ± 0.035 ps – τ(B0) = 1.508 ± 0.025 ± 0.043 ps – τ(Λb)/τ(B0) = 0.864 ± 0.052 ± 0.033
• arXiv:1204.2340, accepted by PRD • Compare to other values (2011):
– τ(Λb) = 1.425 ± 0.032 ps (PDG 2011) – τ(Λb) = 1.537 ± 0.045 ± 0.014 ps
(CDF, PRL 106, 121804 (2011)) • There remains disagreement among the
measurements in the value of τ(Λb) – Puzzle is not yet resolved
Λb lifetime
PLHC 2012 Stephen Wolbers 30 ) [cm]0
SK /J (-0.15 -0.1 -0.05 0 0.05 0.1 0.15 0.2 0.25 0.3
m
µC
andi
date
s pe
r 50
1
10
210
310
-1(b) DØ, 10.4 fb
DataData fitSignalBackground
) [cm]0 /J (-0.15 -0.1 -0.05 0 0.05 0.1 0.15 0.2 0.25 0.3
m
µC
andi
date
s pe
r 50
1
10
210
310
-1(a) DØ, 10.4 fb
DataData fitSignalBackground
DØ
Summary and Prospects
• DØ and CDF have new and important results on many areas of QCD and heavy quark physics. – Many results are world’s best or the only measurements
of these quantities. • Both experiments continue analysis of the full Run 2 dataset. • The emphasis will be on higher precision and use of the
unique capabilities of the Tevatron datasets. • You can expect to see important and interesting results for
some time to come.
PLHC 2012 Stephen Wolbers 31
Z + b jets • Full CDF Run 2 dataset is
used (9.1 fb-1) • Z->µµ and Z->ee events are
selected using an ANN • Templates are used to fit b
jet, c jet and light jet contributions
• Total Z+b jet cross section is normalized to Z+inclusive jets and Inclusive Z events
• The results for the differential cross section is calculated and agrees with MCFM NLO calculations
PLHC 2012 Stephen Wolbers 33
CDF
[GeV/c] jetT
p20 30 40 50 60 70 80 100
-1 [
GeV
/c]
T/d
pZ+
bjet
d
�• Z 1
/
-710
-610
-510
-410
-1CDF Data - 9.13 fbSystematic uncertainties
2T,Z
+p2Z=M2NLO MCFM Q
MSTW 2008 NLO PDFCorrected to hadron level
CDF Run II Preliminary
1 b-jet )+- l+ l(*Z/
Dat
a/Th
eory
1
2
2T,Z
+p2Z=M2NLO MCFM Q Syst. unc.
0; Q=0.5 Q0Q=2 Q PDF unc.
[GeV/c] jetT
p20 30 40 50 60 70 80 100
Dat
a/Th
eory
1
2
2T,Z
+p2Z=M2NLO MCFM Q 0; Q=0.5 Q0 Q=2 Q
2TH=0.5 2NLO MCFM Q
2T,jet
NLO MCFM Q= p
Z + b jets
• σ(Z+b-jet)/σ(Z) = [0.261 ± 0.023 ± 0.29]% • σ(Z+b-jet)/σ(Z) = 0.23% (NLO + MCFM, Q2=mZ
2+pT,Z2)
0.29% (NLO + MCFM, Q2=<pT,jet>2
PLHC 2012 Stephen Wolbers 34
CDF
• Analysis uses full CDF dataset
• Neural-net used to separate signal and background
• ~11,000 J/ψϕ events are analyzed
• A Likelihood fit was used to extract parameters: – ΔΓs and βs
J/ψϕ
PLHC 2012 Stephen Wolbers 35
BRIEF ARTICLE
THE AUTHOR
Some sentence as a test. x = φ
Bs → J/ψφ
1
CDF
• CDF update of βsJ/ψϕ
measurement • The confidence interval
of ϕs is measured to be[-0.60, 0.12] rad at 68% CL, in agreement with the CKM value and recent LHCb and DØ values.
PLHC 2012 Stephen Wolbers 36
BRIEF ARTICLE
THE AUTHOR
Some sentence as a test. x = φ
Bs → J/ψφ
1
CDF
Z/γ* + jets
• Full CDF Run 2 dataset (9.4 fb-1) • Jets are reconstructed using midpoint algorithm with R=0.7
and pT jet>30 GeV and |yjet|<2.1 • Z/γ*->µµ or ee • Backgrounds estimated using MC and data-driven techniques
PLHC 2012 Stephen Wolbers 37
]2 [GeV/cllZM40 60 80 100 120 140
)]
2 [
fb /
(GeV
/cZ
/dM
d
-110
1
10
210
310 -1Data - 9.43 fbTotal PredictionZ+QCD, W + jettt
ZZ, ZW, WW + jet Z
CDF Run II Preliminary1 jet) + -e+ e*(Z/
]2 [GeV/cllZM40 60 80 100 120 140
)]
2 [
fb /
(GeV
/cZ
/dM
d
-110
1
10
210
310-1Data - 9.44 fb
Total PredictionZ+QCD, W + jettt
ZZ, ZW, WW + jet Z
CDF Run II Preliminary1 jet) + -µ+µ *(Z/CDF
Z/γ* + jets
• Results are unfolded to hadron level and compared to several theoretical predictions
• Comparisons are made with theory.
PLHC 2012 Stephen Wolbers 38
[
fb]
je
tsN
1
10
210
310
410
CDF Run II Preliminary
N jets inclusive ) + -l+ l*(Z/2 > 25 GeV/cl
T| < 1.0; pl; |µl = e,
2.1| jet 30 GeV/c, |Y jetT
p
-1 CDF Data L = 9.44 fb
Systematic uncertainties
NLO BLACKHAT+SHERPA
MSTW2008NLO PDF
Corrected to hadron level
)ZT + E
Tj pj (2
1 = ITH 2
1 = 0µ
jetsN1 2 3 4
Dat
a / B
LACK
HAT
1
1.5
2
2.5 NLO BLACKHAT+SHERPA
LO SHERPA (no shower)/2 (NLO)
0µ = µ ;
0µ = 2µ
Dat
a / T
heor
y
1
2
3 ALPGEN+PYTHIA
Tune P2011s Matched
variationsCKKWs - QCD
1
1.5
2 POWHEG+PYTHIA
Tune Perugia 2011/2
0µ = µ ;
0µ = 2µ
jetsN1 2 3 4
1
1.2
NLO LOOPSIM+MCFMn
NLO MCFM/2
0µ = µ ;
0µ = 2µ
Dat
a / T
heor
y
1
2
3-1 CDF Data L = 9.44 fb
Systematic uncertainties
ALPGEN+PYTHIA
Tune P2011s Matched
variationsCKKWs - QCD
1
1.5
2
2.5 POWHEG+PYTHIA
Tune Perugia 2011
/20µ = µ ;
0µ = 2µ
1
1.2NLO LOOPSIM+MCFMn
NLO MCFM/2
0µ = µ ;
0µ = 2µ
jetsN1 2 3 4
1
2
3 NLO BLACKHAT+SHERPA
LO SHERPA (no shower)
/2 (NLO)0µ = µ ;
0µ = 2µ
N jets inclusive ) + -l+ l*(Z/
CDF Run II Preliminary
CDF
ΔAcp(D0->hh)
• Result: ΔACP=[-0.62±0.21 ±0.10]% 2.7σ different from 0 CDF public note 10784 Using the equation: Acp=Acp
dir+(<t>/τ)Acpind
One can plot: ΔAcp
dir vs Acpind
This result is a confirmation of LHCb measurement: ΔAcp=[-0.83±0.21±0.11]%
P2012 Stephen Wolbers 39
[%]indCPA
-2 0 2
[%]
dir
CPA
-2
0
2
CDFCPARABAB CPA
BelleCPA LHCbCPA
RABAB A BelleA LHCbA
2-dim 68.27% CL2-dim 95.45% CL2-dim 99.73% CL1-dim 68.27% CL
-510×P-value = 8.04No CP violation
CDF