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University of Rochester Participation in CDF. Outline. Introduction/Group Members Our Operational Responsibilities Physics Pursuits Top Physics Non-Standard Top Coupling, Dilepton signature, New physics search in Dileptons, Top to taus Electroweak Physics,
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University of RochesterParticipation inCDF DOE, July 23, 2003, P.Tipton
Outline • Introduction/Group Members • Our Operational Responsibilities • Physics Pursuits • Top Physics • Non-Standard Top Coupling, Dilepton signature, New physics search in Dileptons, Top to taus • Electroweak Physics, • W,Z production rates and asymmetries, extracting PDFs • Search for heavy bosons 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 (entering w/ MS) -G.-B. Yu (entering w/ MS) • Kevin McFarland (75%): • -Anthony Vaiciulis • Gilles deLentdecker • J. Chvojka (entering) • S. Demers (4th year) • B. Y. Han (1st year) • B. Kilminster(graduating) • Jedong Lee (3rd 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
The Rochester CDF Group • 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 • Cabling and Power Supply Specifications DOE, July 23, 2003, P.Tipton
Rochester Silicon Operations, Cont. • Cooling and Interlock Operations/On-Call (All) • UR Person on call 24-7 for Cooling and Interlocks • Tevatron Abort and Radiation Monitoring/Radiation Safety Officers (E. Halkiadakis, A.Hocker, R. Eusebi) • Silicon Power Supply Working Group (A.Hocker, A.Ivanov) • Silicon Leakage-current monitoring (Hocker, Eusebi) • Silicon Online Monitoring (Halkiadakis, Coca) • Typically take 95% of data with about 85% of silicon useful June 2002 May 2003 Improved silicon coverage DOE, July 23, 2003, P.Tipton
3rd Area of Focus:Level-3 / Data Hub(McFarland) • Software trigger based on offline reconstruction • Current→ Upgraded Bandwidth • Input rate: 80→150 MB/sec • Output: 20→60 MB/sec • Level-3 selections determine offline datasets after processing • Seeds both offline production and user analysis • “Data Hub” takes accepted Level-3 events, logs them and distributes to online monitoring system DOE, July 23, 2003, P.Tipton
Level-3 / Data Hub Operations • Both Level-3 and the Data Hub are critical online systems • require extensive pager coverage, hardware and software maintenance • Level-3 Operations (deLentdecker, Demers, B-Y Han, KSM) • Rochester personnel create all Level-3 triggers in trigger DB • Responsible for testing new filter code • Maintain software I/O infrastructure (interface between filtering software and online system) • Data Hub Operations (Vaiciulis, Kilminster, Lee) • Vaiciulis serves as Data Hub sub-project leader • Rochester group carries most of pager load • Hardware maintenance (RAID arrays), software upgrades • Data Hub is key DAQ monitoring point; frequent requests for minor updates DOE, July 23, 2003, P.Tipton
Current Level-3 / Data Hub Development • Level-3 Output reduction (deLentdecker, Demers, McFarland) • Level3Summary replaces and summarizes Level-3 reconstruction results • reduces event size ~25%. Adds permanent record of Level-3 results • Data Hub Operations(Vaiciulis, Kilminster, Lee, Clark) • to improve yield for B physics (hadronic Bs final states), CDF has recently proposed doubling the data rate out of Level-3 • requires a major increase in data hub bandwidth • recent internal review has advised developing a system with triple the bandwidth within one year • Vaiciulis, Clark (NSF REU) doing preliminary tests with IDE-RAID based networkp-attached fileservers • portion of McFarland CAREER award not for outreach purchased test hardware for data hub upgrade 3ware IDE RAID controller for low-cost NAS-based Data Hub DOE, July 23, 2003, P.Tipton
290 pb-1 delivered ~220 pb-1 recorded Run 1 luminosity CDF Data-Taking In first 6 months of 2003, UR Scientists provided 150 8-hour data-taking shifts A. Hocker is current CDF Operations Manager ~195 of 225 pb-1 goal delivered y.t.d. Typically run with 85-90% efficiency Ultimately collect 4-8 fb-1 Between ~67 and 125 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
Top Physics DOE, July 23, 2003, P.Tipton
Search for Non-Standard tbW Vertex KM,BJK ^ { HW = J • P -1 Left handed F-(cos Ψ*l) ~(1 – cos Ψ*l) 2 0 LongitudinalF0(cos Ψ*l) ~(1 - cos Ψ*l 2) +1 Right handed F+(cos Ψ*l) ~(1 +cos Ψ*l)2 = M2lb = ½ (M2T – M2W)(1 + cosΨ*l) CDF Run I Preliminary Result: (Using ttbar dilepton, and lepton+jets events with 1 and 2 SVX b-tagged jets) fV+A= -0.21+0.42-0.25 ± 0.21 fV+A < 0.80 @ 95%CL 2000 pb-1 Run II : expected uncertainties ±0.1 (stat), ± 0.11 (sys) SM V-A Theory: 30% F- 70%F0 <0.04% F+ (Mb) fV+A : 0: corresponds to all V-A, (0 % right-handed W’s) 1: corresponds to all V+A (30% right-handed W’s) 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 Tipton’s Group contributed to all aspects of this analysis 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 in the Dilepton Channel A. Hocker new co-leader of Top Dilepton Group Approximately doubles our acceptance and Uses ~125pb-1 Not Yet ‘Blessed’ • Theoretical prediction: (6.7 +/- 0.5) pb DOE, July 23, 2003, P.Tipton
Tau Dileptons: (e or m) t + jets • Motivation: t b may have contributions not apparent in first and second generation dileptons • from either non-standard amplitudes or even from things other than top (e.g., high tanβ SUSY) • Problems: • jet to fake rates are 1-2 orders of magnitude higher than e or μ • not fully reconstructed, Z+jets background higher • McFarland’s Rochester group responsible for analysis(Demers’ thesis, Vaiciulis, Insler & Petruccelli – former REU students) • Recent progress: • reduced largest background in Run 1 by an order of magnitude by pseudo-reconstruction of the ditau mass (Demers, Petruccelli) • optimization of cuts to lower jet fake rate (Vaiciulis) • Expect 1st result this fall Z→+jets pseudo Mreconstruction DOE, July 23, 2003, P.Tipton
Testing SM with Dilepton Kinematics:The PKS test 1: We plan to use the product of KS tests (PKS) to determine how consistent the kinematic features of the dilepton events are with the SM. 2: We devised an a-priori technique to handle a possible excess of events in the high-energy tails of kinematic distributions, like it was in Run I. The PKS method isolates a subset of most unlikely events and determines its significance. Missing Et : Run I dilepton sample DOE, July 23, 2003, P.Tipton
Chosen kinematic variables. ttbar versus SUSY Angle between them Missing Et Flm Top Dilepton topological variable (goodness-of-fit from NWT) Pt of the leading lepton DOE, July 23, 2003, P.Tipton
Electroweak Physics 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 W. Sakumoto,E. Halkiadakis, J.D. Lee, M.Coca, A. Hocker • 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
·B(Z0ee) = 2676stat15sys16lum pb ·B(Z0mm) = 2466stat12sys15lum pb .B(Z0l+l-) Sakumoto, J.D.Lee, E. Halkiadakis 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
Analyses with W/Z/Drell-Yan Rates and Asymmetries • Run 1 (0.1 fb-1) Achievements of Rochester group • W lepton charge asymmetry (Bodek, Fan) • Reduced error on W Mass from PDF uncertainties from 100 to 15 MeV • Makes possible precision measurement of W mass at hadron colliders! • Use of Silicon to measure charge of forward electron tracks using extrapolation of track stubs in sillicon to shower centroid (Bodek, Fan) • Extended Z and Drell-Yan forward-backward asymmetry and rapidity distributions(Bodek, Sakumoto, Chung) • Asymmetry sensitive to Z’ or other high mass states (2 sigma discrepancy at high mass in Run 1 data) • Z rapidity constrains PDFs • Run 2 (2 fb-1) we are continuing this tradition of novel analyses with these samples • repeat Z rapidity (gain in statistics important) • high mass Drell-Yan (Z’ search), new W asymmetry technique DOE, July 23, 2003, P.Tipton
Z/Drell-Yan FB Asymmetry Run I analysis - Bodek/Chung example of 500 GeV Z’ (E6 model) little observable rate effect, but large asymmetry change (Bodek, Baur) DOE, July 23, 2003, P.Tipton
Drell-Yan: Z’ Search, Z-q couplings • Starting from this hint, we are proposing to combine rate AND asymmetry information to search for Z’ signal in Drell-Yan(Lee thesis, deLentdecker, McFarland) • leads to increased sensitivity • Can also use Drell-Yan FBasymmetry to probe for non-standard NC couplings of quarks(deLentdecker, McFarland) • complementary to NuTeV and atomic parity violation as precise probes of Z coupling to light quarks rate and asymmetry Discovery probability rate only DOE, July 23, 2003, P.Tipton
Z Rapidity Distribution Run I analyses (Z- Bodek/Liu), (W - Bodek/Fan). Using plug electrons together with SVX tracking (Rochester plug-Rochester SVX group), MC shows definitive measurements of PDFs Z rapidity distributions and W asymmetry. 2 fb-1 Run 1 results are statistically limited; Chung/J. Han working on Run 2, particularly forward acceptance. Run II Analysis Bodek/Chung/J.Han DOE, July 23, 2003, P.Tipton
W Charge Asymmetry Run 1 (Bodek, Fan): established d/u ratio of proton. However, measurements at high rapidity are difficult to interpret; sensitive to W pT Run 2 (Bodek, McFarland, B. Han, G.Yu): statistics will improve, but interpretation difficult. Need a new technique direct measurement of W rapidity! 2 fb-1, Run II analysis Bodek/McFarland/B.Han/Gyu 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
Conclusions • U or R continues to play an indispensable role in CDF • Our Contributions to Operations for Calorimetry, Silicon and Trigger/DAQ are essential to CDF data-taking • These put us at the top of CDF University groups with critical operational commitments • CDF physics program for Run II is broad and compelling, even if only 4fb-1 are collected • Many ways to make precision tests of the Standard Model in top and EWK sector. • UR led CDF physics program is also broad and compelling • marked by continued innovation DOE, July 23, 2003, P.Tipton