Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August
description
Transcript of Hot Topics from CDF and D0 D.Glenzinski Fermilab ICHEP 2006 01-August
Hot Topics from CDF and D0
D.GlenzinskiFermilab
ICHEP 200601-August
01-Aug-2006 D.Glenzinski, Fermilab 2
Fermilab Tevatron
CellularField
Main Injector
Tevatron
DØCDF
Chicago
Wrigley Field • pp collider at world’s
highest energy
Ecm = 2 TeV
• Run-I 1990-1995 (110 pb-1 /experiment)
• Run-II 2001-2009 (6-8 fb-1 / exp expected)
• Performing excellently
01-Aug-2006 D.Glenzinski, Fermilab 3
Tevatron Run-II
• Data set has doubled every year
• ICHEP-04 Results : 200 pb-1
• ICHEP-06 Results : 1000 pb-1
2002 2003 2004 2005 2006
Del
iver
ed L
umin
osity
pb-1
(per experiment)
01-Aug-2006 D.Glenzinski, Fermilab 4
z
y
x))2/ln(tan(
Experiments: CDF
FeaturesFeatures:
• Precision silicon vertexing
• Large radius drift chamber (r=1.4m)
• 1.4 T solenoid
• EM+HAD Calorimetry
• muon chambers (|| < 1.1)
• Particle Identification
01-Aug-2006 D.Glenzinski, Fermilab 5
Experiments: CDF
01-Aug-2006 D.Glenzinski, Fermilab 6
Experiments: DZero (D0)
FeaturesFeatures:
• Precision silicon vertexing
• Outer Fiber Tracker (r=0.5m)
• 2.0 T solenoid
• EM+HAD Calorimetry
• muon chambers (|| < 2.0)
01-Aug-2006 D.Glenzinski, Fermilab 7
Experiments: D0
01-Aug-2006 D.Glenzinski, Fermilab 8
Tevatron Results Published
• From Run II:– 41 Physics publications by CDF– 33 Physics publications by D0– In 2005: 1 Tevatron publication every 7 days
• So far in 2006– Each experiment has ~15 Published+Accepted,
plus another ~15 submitted analyses
• At this conference– A total of 39 talks in parallel sessions
01-Aug-2006 D.Glenzinski, Fermilab 9
Tevatron Results at ICHEP-06• Parallel Speakers
– F.Canelli, A.Hocker, J.Nielsen, C.Hill, K.Hatakeyama, A.Kupco, M.Sanders, C. Schwanenberger, S.Blessing, M.Verzochi, G.Bernardi, D.O’Neil, D.Wicke, T.Moulik, M.Strauss, G.Borrisov, A.Nomerotski, S.Anderson, W.Taylor, E.Kajfacz, H.Greenlee, T.Hebbeker, P.Savard, I.Gorelov, B.Kilminster, E.Lipeles, M.Lancaster, A.Kraan F.Wuerthwein, P.Busey, R.Field, S.Giagu, S.Farrington, L.Pinera, M.Kreps, Y.S.Chung, A.Hamilton, A.Pronko, W.Wagner
• Plenary Speakers– R. Barlow “Rare B and Tau Decays”– E. Gallo “Beyond the Standard Model (Experiment)”– D. Wood “Precision Electroweak Results”
01-Aug-2006 D.Glenzinski, Fermilab 10
with 1 fb-
1
1.4 x 101
1 x 1011
6 x 106
6 x 105
14,0005,000
100 ~ 10
Pro
duct
ion
cros
s-se
ctio
n (b
arns
)
In 1 fb-1
Tevatron Physics Program(b)
• QCD• Heavy Flavor• Electroweak• Top Quark• New Phenomena
I Will discuss only a fewof the “Hottest” Results
• QCD• Heavy Flavor• Electroweak• Top Quark• New Phenomena
01-Aug-2006 D.Glenzinski, Fermilab 11
Hot Topics (Doug’s Opinion)
• Latest Bs Mixing Results
• Latest Top Mass Results
• Latest New Phenomena Results
Our raison d’etre Unique to Tevatron Program
Have significant impact
01-Aug-2006 D.Glenzinski, Fermilab 12
Bs MixingBs Mixing
D0 Results using 1 fb-1
CDF Results using 1 fb-1
01-Aug-2006 D.Glenzinski, Fermilab 13
B s
Bs
Bs Mixing: Motivation
• Bs particles can change into their anti-particles
• The rate at which Bs Bs oscillate : ms
• Important consistency check of CKM quark-mixing Matrix in Standard Model: ms ~ Vts
01-Aug-2006 D.Glenzinski, Fermilab 14
Bs Mixing: Basics
• Probability that Bs at t=0 decays as Bs at time t
• Experimentally, measure Asymmetry as a function of proper decay time
P(mixed) 1
2e
t
(1 cosmst)
A(t) # unmixed(t) - #mixed(t)
# unmixed(t) + #mixed(t)
01-Aug-2006 D.Glenzinski, Fermilab 15
Bs Mixing: Basics
Perfect Detector Actual
01-Aug-2006 D.Glenzinski, Fermilab 16
Bs Mixing: Ingredients
• For each event we need to determine
1)Bs or Bs at production?
1)Bs or Bs at decay?
1)Proper decay time
Signif NBD
2
2 e
(ms t )2
2 NB
N total
determined using “Flavor Taggers” D2
determined by reconstruction of Bs at decay t
determined by reconstruction of Bs at decay NB
mixedor
unmixed?
01-Aug-2006 D.Glenzinski, Fermilab 17
Ds , K*K ,
K K , K* K
Bs Mixing: 1) Identify Sample
• Bs is reconstructed via semi-leptonic decays
Bs Ds e, Ds
CDF 1 fb-1
Eve
nts
/ 0.
001
GeV
/c2
Ds mass [GeV/c2]
01-Aug-2006 D.Glenzinski, Fermilab 18
Bs Mixing: 1) Identify Sample
• Bs reconstructed via hadronic decays: unique to CDF
Bs Ds , Ds
Mass of Bs (GeV/c2)
CDF1 fb-1
01-Aug-2006 D.Glenzinski, Fermilab 19
Bs Mixing: 1 fb-1 Yields
# reconstructed Bs
D0 CDF
Semi-leptonic 36,500 37,000
Hadronic - 3,600
Next, determine proper decay time…
01-Aug-2006 D.Glenzinski, Fermilab 20
Bs Mixing: 2) Proper Decay Time
• Determine proper decay time from final state:
+
Ds-
LT
x
yproduction vertex
Bs decayvertex
LT MBs
PTvtx
+
determined from Monte Carlo (MC) simulation
01-Aug-2006 D.Glenzinski, Fermilab 21
Bs Mixing: Decay Time Resolution
• Hadronic decays have excellent proper time resolution
Semileptonic Decays
<> ~ 45 m
Hadronic Decays
<> ~ 25 m
proper decay time resolution () / cm
01-Aug-2006 D.Glenzinski, Fermilab 22
b
b
Bs Mixing: 3) Flavor Tagging
• B-Hadron Production at the Tevatron– Predominantly produced in bb pairs– b and b hadronize independently
Bd, B+, b, …
Bs
A) Opposite Side Tag (OST)
Infer production flavor knowing flavor of the other b in the event
B) Same Side Tag (SST)
Infer production flavor knowing flavor of fragmentation tracks
K-
01-Aug-2006 D.Glenzinski, Fermilab 23
Bs Mixing: 3) Flavor Tagging
• Flavor Taggers are characterized by:
• The effective statistics depend on these terms:
efficiency : dilution : D = 2(Purity) - 1
A(stat) ~ NB D2
01-Aug-2006 D.Glenzinski, Fermilab 24
Bs Mixing: Flavor Tagging
• Determining the dilution:
Bd, B+, b, …
BsB-For OST
Compare taggerdecision to knownflavor using fully
reconstructed B
For SST
Determined from MC. Validate MC usingreconstructed B
+
Dilution [%]
01-Aug-2006 D.Glenzinski, Fermilab 25
Bs Mixing: Flavor Tagging Performance
D2
D0 CDF
OST 2.5% 1.5%
SST - 3.5%
Total 2.5% 5.0%
01-Aug-2006 D.Glenzinski, Fermilab 26
Bs Mixing: Sensitivity
• “Sensitivity” = expected 95% CL upper limit on ms
• Determined from data
World 2006: 18
D0 2006: 17
CDF 2006: 25
ms Sensitivity (ps-1)
01-Aug-2006 D.Glenzinski, Fermilab 27
Bs Mixing: Measuring ms
• Look for evidence of Bs mixing using Amplitude Scan– Fourier transform to frequency domain
– Determine amplitude for fixed ms
– Scan ms : Amplitude = 1 at true ms, 0 otherwise
ms (ps-1)
01-Aug-2006 D.Glenzinski, Fermilab 28
Bs Mixing: D0 Results (Mar-06)
17< ms < 21 ps-1 @ 90% CL
PRL 97 (2006) 021802
1 fb-1
(Aug-06)
8% probability Random tags would look as significant
New! 50% more Bs
1 fb-1
For more details see the talk by T.Moulik.
01-Aug-2006 D.Glenzinski, Fermilab 29
Bs Mixing: CDF Results (Apr-06)
ms = 17.31 (sta) 0.07 (sys)0.2% probability Random tags would look as significant
CDF 1fb-1
hep-ex/0606027 (accepted by PRL)
For more details see the talk by S.Giagu.
+0.33-0.18
01-Aug-2006 D.Glenzinski, Fermilab 30
Bs Mixing: Constraints
• measured ms agrees with SM prediction
• relative precision of measured
ms)/ms = 1.5%
md)/md = 1.0%
• precision of measured ms is statistics limited
(syst)/ms < 0.5%
01-Aug-2006 D.Glenzinski, Fermilab 31
• use measured ms to constrain CKM
• agrees with SM prediction
• x5 more precise than previous determination
• limited by Lattice uncertainty
Bs Mixing: Constraints
Vtd
Vts
= md
ms
mBs
mBd
0.208 0.0020.001 (stat) -0.007
0.008(theor)
01-Aug-2006 D.Glenzinski, Fermilab 32
Bs Mixing: Constraints
For latest fit results see talks by S.T’Jampens, V.Vagnoni,and M.Bona
01-Aug-2006 D.Glenzinski, Fermilab 33
Bs Mixing: New Physics Constraints
• Use ms and CP violation in Bs sector to constrain New Physics contributions
– Bs sector largely unexplored
– Bs sector largely independent of Bd sector
– Bs sector more sensitive than Bd sector
• New Physics can affect ms and CP phase ()
BsSM ~ 1, Bd
SM ~ 20
ms = CNP msSM, Bs = Bs
SM + NP
01-Aug-2006 D.Glenzinski, Fermilab 34
Bs Mixing: NP Constraints
Bs = BsSM + NP
ms = CNP msSMConstraint from
ms, s, ACH
combined
XSM
CNPBs
NP(B
s) /
deg
rees
dark: 68%light: 95%
For decails see:hep-ph/0012219, hep-ph/0406300,
hep-ph/0605028, talks by S.T’Jampens and V.Vagnoni
• Recall
01-Aug-2006 D.Glenzinski, Fermilab 35
Bs Mixing: NP Constraints
Bs (rad)
New!
1 fb-1
SM
• CDF and D0 can also constrain
• D0 combines 3 measurements to get first constraints
• precision of all 3 are statistics limited
– more data to come– CDF + D0
• direct CP using flavor tagged decays
Bs J / For more details see the talk by G.Borissov.
01-Aug-2006 D.Glenzinski, Fermilab 36
Top-Quark MassTop-Quark Mass
D0 Results using 0.4-1 fb-1
CDF Results using 1 fb-1
01-Aug-2006 D.Glenzinski, Fermilab 37
Top Mass: Motivation
• Mt is a fundamental parameter of the Standard Model
• Since Mt is large, quantum loops involving top quarks are important to include when calculating precision observables (e.g. sin2w, Rb, Mw,…)
• Within SM, particularly important to help constrain MH
W Wt
b
H Ht
t
Zt
t
b
b
W
01-Aug-2006 D.Glenzinski, Fermilab 38
Top Mass: Motivation
• Mt important input for any model trying to describe high energy particle physics
– In MSSM at tree level: Mh<Mz (very excluded)
w/ Mt loop corrections: Mh < 135 GeV
– Mt impacts soft-SuSy breaking phenomenology
– Mt plays critial role in verifying gauge unification through RGEs
• Precision Mt crucial to understanding underlying theory of HEP, whether SM or SuSy or …
01-Aug-2006 D.Glenzinski, Fermilab 39
Top Mass: Basics
• Top quarks predominantly produced in pairs via the strong interaction
• Production cross-section: ~ 7 pb at Tevatron
q
q
t
t 85%
t
t
g
g15%
01-Aug-2006 D.Glenzinski, Fermilab 40
Top Mass: Basics
• Because Mt > Mw + Mb, and Vtb>> Vts,Vtd
• Final state determined by W decays
(top) ~ 1
10 (hadronization)
BR(t W b) ~ 100%
tt W bW b bb “Di-Lepton”
tt W bW b q q bb “Lepton+Jets” “All Jets”
tt W bW b q q q q bb
01-Aug-2006 D.Glenzinski, Fermilab 41
Top Mass: Basics
• We measure Mt in each of these final states
– Dilepton (DIL)
– Lepton+Jets (LJT)
– All Jets (AJT)
• Compare across channels for consistency
• Combine all channels for improved precision
01-Aug-2006 D.Glenzinski, Fermilab 42
Top Mass: Ingredients
• To measure Mt we need to:
1)Collect top quark sample
2)Reconstruct observable sensitive to Mt
3)Unfold experimental effects
Mreco (EW ,p W )2 (Eb,
p b )2
Mreco M t
01-Aug-2006 D.Glenzinski, Fermilab 43
Top Mass: 1) Collect Sample
• Dilepton: ttllbb2 high energy leptons, missing energy (), 2 jetsIn 1 fb-1: #signal~50, Purity~65%
• Lepton + Jets: ttlqq bb1 high energy lepton, missing energy (), 4 jets (1 Bjet)In 1 fb-1: #signal~230, Purity~90%
• All Jets: ttqq qq bb 6 jets (1 Bjet)
In 1 fb-1: #signal~200, Purity~30%
For more details see talks by C.Hill and D.O’Neil
01-Aug-2006 D.Glenzinski, Fermilab 44
Top Mass: 1) Collect Sample
• cross-sections and kinematics agree with Standard Model
tt production cross- section (pb)
For more details see talks by D.Wicke, A.Kraan, S.Anderson
01-Aug-2006 D.Glenzinski, Fermilab 45
Top Mass: 2) Event Reconstruction
tt W bW b q q bb
Have
Jet 1Jet 2Jet 3Jet 4
LeptonEt
Need
qq’bb
Lepton
?
Combinatoric Background
Have Jet EnergiesNeed Parton Energies
“Jet Energy Scale”(JES)DIL : 2 combinationsLJT: 12 combinationsAJT: 90 combinations
01-Aug-2006 D.Glenzinski, Fermilab 46
Top Mass: 2) Reconstruction
Jet Energy Scale == Absolute Mass Scale
M(qqb) / GeV/c2
UncorrectedCorrected
Monte CarloMt = 175 GeV/c2
• hadronization, non-linearities, pile-up, multiple-interactions, underlying event
• From Data and MC
• known to ~3% for Mt
jet energies
• Leading Run I syst
• Reduced in Run II
01-Aug-2006 D.Glenzinski, Fermilab 47
Top Mass: 2) Reconstruction
• Run II analyses further constrain JES
– In-situ constraint possible by comparing observed
Mqq to known Mw (in LJT and AJT channels)
– with 1 fb-1, reduces (JES) systematic by factor of 2
(JES) will scale with sample statistics
tW
b
q
qMqq = Mw
01-Aug-2006 D.Glenzinski, Fermilab 48
Top Mass: 3) Unfold Exp Effects
• Use detailed Monte Carlo to unfold experimental effects and determine Mt from Mreco
m(reco) GeV/c2
“data”
Lepton+Jets ChannelDilepton Channel
true
Mt
measured Mt
01-Aug-2006 D.Glenzinski, Fermilab 49
Top Mass: Results
• Excellent results in each channel
• Combine all CDF+D0, Run-I+Run-II
• Account for all correlations
• Uncertainty:
Mt(stat) = 1.2
Mt(JES) = 1.4 GeV/c2
Mt(syst) = 1.0
Stat+JES scale with sample sizeMt determined to 1.2%!
(cf. http://tevewwg.fnal.gov)
New!
01-Aug-2006 D.Glenzinski, Fermilab 50
Mt(jes)
(Signal)(Bgd)
(Other)
(syst)(stat)
(total)
170.9
174.0
164.5
LJT AJT DIL
the most precise result in each channel
Top Mass: Results
Jet Energy Scale is leading systematic in all channelsISR, FSR, PDF, NLO effectsComposition, Normalization, and ShapeMC statistics, Method, B-tagging, etcuses in-situ JES calibration comparing Mqq to MwSingle most precise determination
For more details see talk by F.Canelli
(in units of GeV/c2)
01-Aug-2006 D.Glenzinski, Fermilab 51
Top Mass: Results
• The channels are consistent at 15% level
01-Aug-2006 D.Glenzinski, Fermilab 52
Top Mass: Future
• Extrapolations based on present methods– Solid: pessimistic– Dash: optimistic– Reality: in between
• Have surpassed Run-II goal
• TeV will measure Mt with <1% precision
01-Aug-2006 D.Glenzinski, Fermilab 53
Top Mass Constraints
• Indicates Higgs is light, where our sensitivity best!
01-Aug-2006 D.Glenzinski, Fermilab 54
New PhenomenaNew Phenomena
Where do we stand?
Where will we go?
01-Aug-2006 D.Glenzinski, Fermilab 55
New Phenomena: Motivation
• The Standard Model – is an effective (low Energy) theory– does not include a description of gravity– has shortcomings
• There could be something more… but what?– SuperSymmetry (mSuGra, GMSB, SO(10),…)– Compositeness, 4th Generation, LeptoQuarks– Extra Dimensions, Technicolor
• We look for all of these things
01-Aug-2006 D.Glenzinski, Fermilab 56
Searching for
(thanks to Mark Oreglia)
the Higgs Boson
• Higgs required to generate W, Z masses
• Precision EWK prefers light Higgs
• Most SuSy needs 1 light Higgs
01-Aug-2006 D.Glenzinski, Fermilab 57
Higgs: SM Production
• For MH=140-110: (WH+ZH)=100-300 fb
• For MH=180-140: (ggH)=150-500 fb
01-Aug-2006 D.Glenzinski, Fermilab 58
Higgs: MSSM Production
(MSSM/SM) = 1-100 depending on Susy parameters; Tevatron sensitive to large tan
=h,H,A
01-Aug-2006 D.Glenzinski, Fermilab 59
Higgs: Decay
• In SM most important higgs decays are
• In Susy most important higgs decays are
h bb , + , W W
h bb , +
01-Aug-2006 D.Glenzinski, Fermilab 60
Higgs: Experimental Signatures
• Experimental final state determined by W, Z decays
• The most important for the SM Higgs are
• Each experiment has results in all of these final states
WH ebb , bb
(W)H (W)WW* X, X
ZH e+e-bb , -bb
ZH bb
For more details see talks by B.Kilminster, A.Hocker, and G.Bernardi
01-Aug-2006 D.Glenzinski, Fermilab 61
Expected sensitivity within factor of5-10 of SM for all 110 < MH < 200!
Additional sensitivity from more data, and application of known improvements to all channelsA lot of work - but we will reach SM sensitivities
New! CDF WH,ZH with 1 fb-1
Important at low mass
Differences in single expsensitivity owing to these
luminosity differences
Higgs: Limits
• We combine ~15 CDF+D0 results (250-1000 pb-1)New! D0 ggH, WH with 1fb-1
Important at high massCDF/D0 updates comlimentary
Tev expected = Single experiment @ 1.3 fb-1
(cf. http://tevnphwg.fnal.gov)
01-Aug-2006 D.Glenzinski, Fermilab 62
Higgs: MSSM Sensitivities
Tevatron will have sensitivity to MSSM higgs for all tan>30 and MA<200 GeV/c2
01-Aug-2006 D.Glenzinski, Fermilab 63
Higgs: Progress
SM cross-sections for (di)boson production
CDF 72 pb-1
We~35k evt
D0 96 pb-1
W~xxk evt
Have >106 leptonic Ws in 1 fb-1Tau identification well understood.
D0 177 pb-1
Z e+e-
CDF200 pb-1
Z +-
We have ~105 leptonic Zs in 1 fb-1We have ~103 W,~102 Z in 1 fb-1
W+W -
We have ~102 WW in 1 fb-1
WZ
We have ~10 leptonic WZ in 1 fb-1
• with 1 fb-1 we’re observing cross-sections of order 1 pb in final states similar to SM H
• expect a factor of ~8 more data
• experimental sensitivity on track and will get better
– extended b-tagging– improved jet resolution
• CDF and D0 enthusiastically pursuing the Higgs
01-Aug-2006 D.Glenzinski, Fermilab 64
Conclusions
• Tevatron performing well
– 1 fb-1/experiment in hand
– Expect 6-8 fb-1/experiment by end 2009
• CDF and D0 performing well
– Publishing wide spectrum of world class results (CDF+D0 2005 avg: 1 published paper/week)
– Ready to take advantage of coming data
– Enthusiastically pursuing New Physics and Higgs
01-Aug-2006 D.Glenzinski, Fermilab 65
Conclusions
• The LHC will inherit
– Precise determination of ms and constraints on CP phase in Bs sector Bs
– Precision Mt (Mt=1.0-1.5 GeV/c2) and
Mw (Mw=15-25 MeV/c2)
– A more restricted New Physics parameter space
– A higgs mass
01-Aug-2006 D.Glenzinski, Fermilab 66
Backup Slides
01-Aug-2006 D.Glenzinski, Fermilab 67
Bs Mixing: Decay Time Resolution
(semi-leptonic) depends on decay time
01-Aug-2006 D.Glenzinski, Fermilab 68
Bs Mixing: Likelihoods CDF
Final significance and measurement of ms using Lhood ratio
logL(ms,A 0)
L(ms,A 1)
min = -6.75
01-Aug-2006 D.Glenzinski, Fermilab 69
Bs Mixing: Likelihoods D0
Resolution K-factor variation BR (BsDsX) VPDL model BR (BsDsDs)
Mar-06
D0 Jul-06
Systematics
01-Aug-2006 D.Glenzinski, Fermilab 70
Bs Mixing: D0 A-Scans for New Modes
Ds K*K
BsDs XBsDs (e X
Ds