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University of Rochester Participation in CDF. 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. Current CDF Group Members.
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University of RochesterParticipation inCDF DOE, July 23, 2003, P.Tipton
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
Current CDF Group Members Three sub-groups function as one on many projects, but primary hardware/physics interests align us as follows: 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) • 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) • 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: PI’s Senior Res. Assoc. Postdoc. Fellows Grad Students Undergrads DOE, July 23, 2003, P.Tipton
CDF • CDF 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
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
CDF Plug Operations Run 2Problem: 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
Rochester Silicon Operations 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
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
CDF, cont Third 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
260 pb-1 delivered ~200 pb-1 recorded Run 1 luminosity CDF Data-Taking ~190 of 225 pb-1 goal delivered y.t.d. Typically run with 85-90% efficiency Ultimately collect 4-8 fb-1 Between ~67 and 130 pb-1 used in analyses presented here DOE, July 23, 2003, P.Tipton
Great Progress in One Year 1 year ago (2002) Now (2003) • 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. Lum1553 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) DOE, July 23, 2003, P.Tipton
Silicon Performance • Inclusive B lifetime with J/y’s ct=458±10stat. ±11syst.mm (PDG: 469±4 mm) • Exclusive B+J/yK+lifetime ct=446 ±43stat. ±13syst.mm (PDG: 502±5 mm) 11 micron resolution 18.4/pb BsJ/yf More mass plots DOE, July 23, 2003, P.Tipton
.B(Wee) ·B(We) = 2.640.01stat0.09sys0.16lum nb NNLO @ s=1.96 TeV‡: 2.69 0.10 nb • Candidates: 38625 in ~ 72 pb-1 • Backgrounds ~6% (dominated by QCD) ‡ Nucl. Phys. B359,343 (1991) Phys.Rev. Lett. 88,201801 (2002) DOE, July 23, 2003, P.Tipton
Run 2 Measurements of sB(Wen, mn) s•B(Wmn) = 2.70±.04stat±.19syst ±.27lum MT 5547 candidates in 10 pb-1 4561 candidates in 16 pb-1 sW*BR(Wen) (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
·B(Z0ee) = 2676stat15sys16lum pb ·B(Z0mm) = 2466stat12sys15lum pb .B(Z0l+l-) VERY CLEAN • Candidates: 1830 in ~ 72 pb-1 • Backgrounds ~0.6% • Candidates: 1631 in ~ 72 pb-1 • Backgrounds: ~0.9% NNLO@ s=1.96 TeV‡: 252 9 pb ‡ Nucl. Phys. B359,343 (1991) Phys.Rev. Lett. 88,201801 (2002) DOE, July 23, 2003, P.Tipton
W & Cross Sections vs. ECM Our new measurements NNLO DOE, July 23, 2003, P.Tipton
PDG combined Exp PDG SM Theoretical prediction Measure (ppW)(W e)(Z) R= (ppZ)(W)(Z ee) Extract G(W) DOE, July 23, 2003, P.Tipton
- Df vs. ET N jets 2 / tt = 13.2 5.9stat 1.5sys 0.8lum pb NLO@ s=1.96 TeV for Mtop = 175 GeV‡: 6.70+0.71–0.88 pb - stt DileptonChannel: tt llbb Run II Top Dilepton Summary Table: CDF Run II Preliminary - ‡ MLM ‡ hep-ph/0303085(ML Mangano et al) DOE, July 23, 2003, P.Tipton
New Results forstt in the Dilepton Channel: tt llbb Using ~125pb-1 • Theoretical prediction: (6.7 +/- 0.5) pb DOE, July 23, 2003, P.Tipton
Inventing New Experimental and Analysis Techniques 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
Run I versus Run IIRochester analyses 0.1 fm-1 vs 2 fm-1 2 fm-1 Run II analysis - McFarland/Lee Run I analysis - Bodek/Chung DOE, July 23, 2003, P.Tipton
Run I versus Run IIRochester analyses 0.1 fm-1 vs 2 fm-1 2 fm-1, Run II analysis Bodek/McFarland/Han/Gyu 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/Chung/Han DOE, July 23, 2003, P.Tipton
Constraining PDFs : (d/u) with W asymmetry;(d+u) with y distribution for Z’s and W’s Measure W decay lepton charge asymmetry - V-A has opposite asymemtry. Unkown neutrino Z momentum yields two solutions for yw New technique Needed to Limit the Error on W Mass from PDFs uncertainties New technique to unfold the two yw solutions to get the true W production asymmetry -being developed by Bodek, McFarland- expected errors. Shown: U-quark carries more momentum than d-quark DOE, July 23, 2003, P.Tipton
Constraining PDFs : (d/u) with W asymmetry;(d+u) with y distribution for Z’s and W’s W with 0.5 fb-1 generated Z with 1.5 fb-1 - generated 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). DOE, July 23, 2003, P.Tipton
Conclusions • U or R continues to play an indispensable role in CDF DOE, July 23, 2003, P.Tipton