doe, july 23, 2003, p.tipton1 university of rochester participation in cdf
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DOE, July 23, 2003, P.Tipton 2
Outline
•Introduction/Group Members
•Our Operational Responsibilities
•Physics Pursuits
•W/Z Physics
•Heavy Zs
•Top Physics
•W Helicity and New physics search in Dileptons
•Top to taus
DOE, July 23, 2003, P.Tipton 3
Current CDF Group Members
Arie Bodek (50%):
-Howard Budd (50%)
-Pawel DeBarbaro (10%)
-Willis Sakumoto
-Yeon Sei Chung (95%)
-Phil Yoon (4th year)
(acc. Phys., FNAL Support)
-J.-Y. Han (1st year-with MS)
-G.-B. Yu (1st year-with MS)
PI’s Senior Res. Assoc. Postdoc. Fellows Grad Students Undergrads
Kevin McFarland (75%?):
-Anthony Vaiciulis
–Gilles deLentdecker
–J. Chvojka (1st year)
–B. Kilminster(graduating)
–S. Kenezny(4th year)
–Jedong Lee (2nd year)
–B. Y. Han (2nd year)
–Chris Clark (REU)
Three sub-groups function as one on many projects, but primary hardware/physics interests align us as follows:
Paul Tipton (75%):
–Eva Halkiadakis(90%)
–Andy Hocker (90%)
–M. Coca (5th year)
–R. Eusebi (70%, 3rd year)
–Andrew Ivanov (5th year)
–Sarah Lockwitz (REU)
Color KEY:
DOE, July 23, 2003, P.Tipton 4
CDFCDF effort led by Bodek, Tipton, McFarland
We are focused on: –Tests of the SM in and around the top candidate sample
–Production and decay parameters of the Top Quark
–Electroweak physics with W and Z Bosons
–Search for new W and Z Bosons
–Higgs Search
–Much experience from Run I (top discovery, heavy Z searches, etc)
DOE, July 23, 2003, P.Tipton 5
Rochester’s Three Areas of Focus and Operational Responsibility
•Run 2 forward calorimeter --‘endplug’ (Bodek)
–Hadronic section a Rochester-led effort
–Constructed at FNAL with Rochester physicists and technicians doing fabrication, QA.
– Rochester in charge of test beam calibration, calibration at B0, installation, commissioning and operations.
–Fermilab responsibility -phototubes and bases
Note: A lot of Physics (e.g. W Asymmetry, W Mass, PDFs needs the plug.
DOE, July 23, 2003, P.Tipton 6
CDF Plug Operations
Run 2 Problem: Degradation of both EM and Hadron Plug calorimeter response at forward plug (eta)
Investigated ->by our group using the laser monitoring system. Problem narrowed down to degradation of phototubes due to high current associated with beam.
Solution ->(a) Lower the voltage to fix the problem. (b)Correct older data using the laser information
Central-Plug Z mass constant after the application of Laser gain corrections
DOE, July 23, 2003, P.Tipton 7
Rochester Silicon OperationsSecond area of Focus: Silicon Tracking
•Run 2 SVXII (Tipton) –Rochester group contributed to SVXII Ladder and Barrel fabrication
–Silicon Cooling and Interlocks
–Radiation Monitoring and Tevatron abort
–Commissioning and Operations
DOE, July 23, 2003, P.Tipton 8
Rochester Silicon Operations, Cont.Second area of Focus: Silicon Tracking
•Run 2 SVXII (Tipton) –Rochester group contributed to SVXII Ladder and Barrel fabrication
–Silicon Cooling and Interlocks
–Radiation Monitoring and Tevatron abort
–Commissioning and Operations
DOE, July 23, 2003, P.Tipton 9
CDF, contThird area of Focus: Level 3 Trigger/Data Hub
•Level 3 (McFarland) –Responsible for software trigger based on offline reconstruction
–Current→Run2b Bandwidth
–Input rate: 80→200 MB/sec
–Output: 20→60 MB/sec
–“Data Hub” takes accepted Level-3 events, logs them and distributes to online monitoring system
–Level-3 selections determine offline datasets after processing
–Allows CDF to find events in its firehose of a datastream
DOE, July 23, 2003, P.Tipton 10
CDF Data-Taking
Run 1 luminosity
260 pb-1 delivered
~200 pb-1 recorded
Between ~67 and 130 pb used in analyses presented here
Typically run with 85-90% efficiency
Ultimately collect 4-8 fb
~190 of 225 pbgoal delivered y.t.d.
DOE, July 23, 2003, P.Tipton 11
Great Progress in One Year
• L1/L2/L3 rates: 18k/250/75 Hz 6k/240/30Hz ~45e30 ~15e30
• Biggest run: 1553 nb-1 (run 163064) 447 nb-1 (run 145005)
taken May 17-18th 17h w. Si. taken May 17, 11h w Si.
• Highest Init. Lum. 47.5e30 (May 17th) 20.6e30 (May 19th)
• Best store CDF int. Lum 1553 nb-1 (one run) 602 nb-1 (4 runs) (store 2555, May 17th) (Store 1332, May 17th)
• Best “CDF-week” 9.1 (pb-1)/10.3 (pb-1) 2.97 (pb-1)/3.47 (pb-1) (most pb-1 to tape) (week of May 11th) (week of May 16th)
• Best Store Efficiency 94.2% with Si (1 run) 93.2% no Si (4 runs)(May 17th, 9.1 of 10.3 pb-1) (May 16th, 506 of
543 nb-1)
Now (2003) 1 year ago (2002)
DOE, July 23, 2003, P.Tipton 12
Silicon Performance
• Inclusive B lifetime with J/’sc=458±10stat. ±11syst. m (PDG: 469±4 m)
• Exclusive B+J/lifetimec=446 ±43stat. ±13syst. m (PDG: 502±5 m)
More mass plots
BsJ/18.4/pb
11 micron resolution
DOE, July 23, 2003, P.Tipton 13
.B(Wee)
Candidates: 38625 in ~ 72 pb-1
Backgrounds ~ 6 % (dominated by QCD)
‡ Nucl. Phys. B359,343 (1991)
Phys.Rev. Lett. 88,201801 (2002)
·B(W·B(Wee) = 2.64) = 2.640.010.01statstat0.090.09syssys0.160.16lum lum nbnb
NNLO @ NNLO @ s=1.96 TeVs=1.96 TeV‡‡: 2.69 : 2.69 0.10 nb0.10 nb
DOE, July 23, 2003, P.Tipton 14
Run 2 Measurements of We, )
MT
•B(W) = 2.70±.04stat±.19syst ±.27lum
5547 candidates in 10 pb-1 4561 candidates in 16 pb-1
W*BR(We) (nb) =
2.60±0.07stat±0.11syst ± 0.26lum
Run 1 scaled to 1.96 TeV: 2.72±0.02stat±0.09syst ±0.10lum
DOE, July 23, 2003, P.Tipton 15
.B(Z0l+l-)
Candidates: 1830 in ~ 72 pb-1
Backgrounds ~ 0.6 %
·B(Z·B(Z00ee) = 267ee) = 26766statstat1515syssys1616lum lum pbpb
·B(Z·B(Z00) = 246) = 24666statstat1212syssys1515lum lum pbpb‡ Nucl. Phys. B359,343 (1991)
Phys.Rev. Lett. 88,201801 (2002)
Candidates: 1631 in ~ 72 pb-1
Backgrounds: ~ 0.9 %
NNLONNLO @ @ s=1.96 TeVs=1.96 TeV‡‡: 252 : 252 9 pb 9 pb
VERYCLEAN
DOE, July 23, 2003, P.Tipton 17
(W)
(pp(ppZ)Z) (W)(W) (Z (Z ee) ee)(pp(ppW)W) (W (W e e)) (Z)(Z)
RR =
TheoreticalTheoreticalpredictionprediction
PDGPDGSMSM
PDGPDGcombined Expcombined ExpMeasureMeasure
ExtractExtract
RR (W) [GeV](W) [GeV]
ee 9.889.880.240.24statstat0.470.47
syssys
2.292.290.060.06statstat0.100.10ss
ysys
10.6910.690.270.27statstat0.30.3
33syssys 2.112.110.050.05statstat 0.070.07syssys
e+e+ 10.5410.540.180.18statstat0.30.3
33syssys 2.152.150.040.04statstat0.070.07ss
ysys
DOE, July 23, 2003, P.Tipton 18
tt Dilepton Channel: tt llbb
tt tt = 13.2 = 13.2 5.9 5.9statstat 1.5 1.5syssys 0.8 0.8lum lum pbpb
NLONLO @ @ s=1.96 TeV for s=1.96 TeV for
MMtop top = 175 GeV= 175 GeV‡‡: 6.70: 6.70+0.71+0.71 –0.88–0.88 pb pb‡ MLM
vs. ET N jets 2/
CDF Run II Preliminary
-
Run II Top Dilepton Summary Table:
‡ hep-ph/0303085(ML Mangano et al)
SSoouurrccee eeee ee ll llBackground 0.03 ±0.056 0.093 ±0.054 0.00 ±0.037 0.30 ±0.2
+ SM bkg tt 0.57 ±0.08 0.68 ±0.09 .5 ±0.2 2.8 ±0.3 Data 3 5
-
--
DOE, July 23, 2003, P.Tipton 19
Using ~125pb-1
pbLumA
BNttbar )5.02.14.31.9()( ±±±=
××−
=∫ε
• Theoretical prediction: (6.7 +/- 0.5) pb
New Results for tt in the Dilepton Channel: tt llbb
DOE, July 23, 2003, P.Tipton 20
Inventing New Experimental and Analysis Techniques
(1) In Run I- 0.1 fb-1. Rochester’s analysis of the W Asymmetry (Bodek,Fan) has led to the reduction on the error on the W mass from PDF uncertainties from 100 MeV down to 15 MeV. Made precision measurements of the W mass at hadron colliders possible.
-- In Run I - A new experimental technique (Bodek-Fan) to identify e+ and e- was invented for this purpose to extend the asymmetry to the forward direction. It combines extrapolation of tracks in the SVX with the position of the shower centroid in the plug calorimeter. If the centroid was shifter to one side it was an electron, if it was on the other, it was a positron,
-- In run I - This technique was also used to measure the Z and DY forward-backward asymmetry. Z - Y distributions were measured (constrains PDFs). High Mass DY-FB Asymmetry shows 2 sigma deviation from SM (possible Z’ ?).
(2) Run-II Investigating physics with 0.5-1.0 fb-1. Developing newer (Bodek,McFarland) techniques to do physics with W’s, Z’s and DY.
DOE, July 23, 2003, P.Tipton 21
Run I versus Run IIRochester analyses 0.1 fm-1 vs 2 fm-1
2 fm-1
Run I analysis - Bodek/Chung
Run II analysis - McFarland/Lee
DOE, July 23, 2003, P.Tipton 22
Run I versus Run IIRochester analyses 0.1 fm-1 vs 2 fm-1
Run I analyses (Z- Bodek/Liu), (W - Bodel/Fan). Run II: Using plug electrons together with SVX tracking (Rochester plug-Rocheser SVX group), MC shows definitive measurements of PDFs from W and Z y-distributions and asymmetry.)
2 fm-1, Run II analysis Bodek/McFarland/Han/Gyu
2 fm-1Run II Analysis
Bodek/Chung/Han
DOE, July 23, 2003, P.Tipton 23
Constraining PDFs : (d/u) with W asymmetry;
(d+u) with y distribution for Z’s and W’s
New technique to unfold the two yw solutions to get the true W production asymmetry -being developed by Bodek, McFarland- expected errors. Shown:
Measure W decay lepton charge asymmetry - V-A has opposite asymemtry. Unkown neutrino Z momentum yields two solutions for yw Needed to
Limit theError on WMass from PDFs uncertainties
U-quark carries moremomentum than d-quark
New technique
DOE, July 23, 2003, P.Tipton 24
Constraining PDFs : (d/u) with W asymmetry;
(d+u) with y distribution for Z’s and W’s
W generated y distribution for 0.5 fb-1. W has higher statistics but cannot be measured directly. Determine indirectly via decay lepton and deconvolution of the two y1 and y2 solutions with the W asymmetry for Central and Plug electrons.
Z generated y distribution for 1.5 fb-1 Z can be measured directly using Plug-Plug events (but cross section is lower than W). Provides constraints on W y distribution and on (u+d). (get d/u from W Asymmetry).
W with0.5 fb-1generated Z with 1.5 fb-1
- generated