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D Ø and CMS physics program Regina Demina July 23, 2003. Hadron collider program at UR. Rochester is essential institution in D Ø Great number of key D Ø players are or were affiliated with UR at some point in their career It is important to maintain Tevatron program =CDF+DØ
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DØ and CMS physics programRegina DeminaJuly 23, 2003 DOE, July 23, 2003, R. Demina
Hadron collider program at UR • Rochester is essential institution in DØ • Great number of key DØ players are or were affiliated with UR at some point in their career • It is important to maintain Tevatron program =CDF+DØ • Important measurements to come: • Top! – we just opened the door to top physics in Run 1. Run 2 is the time to walk in. Potential role of top quark in EWSB. • Jet (especially heavy flavor) production, W,Z production … • Tevatron program is essential to expedite the way to physics in LHC • UR is making crucial contribution to CMS • UR – bridge from Tevatron to LHC program • Preparation and experience in hadron physics are essential for the fastest way to physics DOE, July 23, 2003, R. Demina
Outline • DØ physics program • Tevatron LHC transition • CMS silicon tracker construction • Work on silicon detectors at UR DOE, July 23, 2003, R. Demina
Focus of DØ physics program • Top quark physics = Hope for surprises • Why is it so heavy? • Why its mass is on the EW scale? • Potential role in EWSB: coupling to gauge bosons • W helicity, • ttj, ttg production • Is it top? – study basic properties, e.g. charge, spin • It is only top? – study kinematics, ttbar invariant mass • Understanding of jets production, heavy flavor • QCD test, background normalization, probe of new physics • “engineering” measurements for LHC DOE, July 23, 2003, R. Demina
Jet production cross section • One of the first run 2 physics results • Dijet mass – new physics probe • Zielinski (QCD convener for 2 years of Run II), Begel, Davis DOE, July 23, 2003, R. Demina
UR for Top cross section Lepton = EM(MU) +track EM showers: Cho CFT: Ginther, Davis Tracking algorithm: Khanov Jet reco: Davis Calorimeter task force: Chan, Zielinski EXAMINE: Canelli Jets+Met Silicon clusters: CSIP: Demina, Khanov B-tagging Matrix element approach (to be applied): Ferbel, Canelli, Estrada Luminosity Lum_ID:Begel, Slattery e+j : Cho l+b-tag: Demina, Khanov Analysis Simulation: Zielinski Color key: PI, Senior RA, Postdocs, Grad. Students DOE, July 23, 2003, R. Demina
Ttbar production cross section • Use NN to improve discrimination between ttbar from W+jets in e+>=4 jets channel. • Inputs: aplanarity(A), scalar ET (HT) D. Cho DOE, July 23, 2003, R. Demina
Ttbar production cross section Demina,Khanov s=7.4+4.4-3.6(stat)+2.1-1.8(sys)±0.7(lum) pb • Allow 3 or more jets in lepton+jets channel, but apply b-tagging • First time in DØ use lifetime based b-tagging! L=45pb-1 e btag DOE, July 23, 2003, R. Demina
W-helicity in top decay • Important measurement that probes top coupling to gauge bosons • Hypothetical top role in EWSB may manifest itself in deviation from Standard Model • Run 1 data • Ferbel, • Canelli (to graduate this summer) • Estrada(graduated) • Great improvements in Run 2: • With 2fb-1 x20 in stat • B-tagging – drastically improve S/N • B-charge tagging – reduce combinatorics in jet assignment SM DOE, July 23, 2003, R. Demina
Ongoing and future analyses • Task B • Zielinski, Begel,Davis: Jet production studies • Cho: top cross section in e+jets • Chan: non-standard coupling to tt prod • C. Garcia: mass resolution in Hbb, Zbb • Pleier: W-helicity, backgrounds to top, heavy flavor production • Task C • Khanov: top x-section with b-tagging • Schwaab: b-charge tagging, W-helicity • E. Grove: b/c separation, b/c g production • ttg, ttg production (need more people) Color key: PI, Senior RA, Postdocs, Grad. Students DOE, July 23, 2003, R. Demina
TevatronLHC transition • Commissioning • Could be lengthy and painful • Experience and preparation is the key: • Ginther (CFT), Demina (SMT), Tipton(SVXII) • Pleier (CMS DAQ, test beam data) • Calibration of detector systems and physics objectson collider data - use methods developed at Tevatron • Physics of hadron environment: • Use of Tevatron data for “engineering” measurements • Zielinski –experience with Tevatron, connection to theory, MC tools • Pleier – heavy flavor production • tt+jets production • L. Orr – theoretical guidance DOE, July 23, 2003, R. Demina
TevatronLHC transition,case study: ttH • Associated ttbar and Higgs(bb) production • One of the discovery channels for low mass Higgs • Tree level at production and decay (unlike ggHgg) • Proof that it is indeed Higgs – probe coupling to two fermions – t and b • To establish the signal in CMS we need • Lepton, jets and missing energy ID and calibration of objects (Zielinski – techniques developed at Tevatron) • 4 b-jets!: B-tagging development and calibration (Demina, Tipton) • Reduce combinatorics in jet assignment – b-charge tagging (Demina, Schwaab) • Understanding production rate (Orr – NLO calculation, Zielinski – MC) • Backgrounds – can be measured at Tevatron(!): • W+bb+jets (Pleier) • tt+jets • Improved mass resolution (C. Garcia’s study) Studies at Tevatron pave the road to discovery at LHC DOE, July 23, 2003, R. Demina
Silicon for CMS • CMS Tracker Outer Barrel (1/3 of the tracker) – US project: Tipton, Demina • 2 production sites:FNAL, UCSB • UR – key institution for FNAL production line. UR DOE, July 23, 2003, R. Demina
UR People on CMS-TOB • Demina: co-leader, liaison with EU, parts delivery • Demina, Ferbel, Korjenevski(50%), undergrads: sensor probing • Tipton: transportation • Pleier(30%), Hocker(10%), Eusebi(30%), Tipton: rod burn-in testing: DAQ, cooling, interlocks • Ginther,Halkiadakis, J. Gielata, A. Sanocka – module/rods construction and mech inspection at FNAL Color key: PI, Senior RA, Postdocs, Grad. Students, Project funds DOE, July 23, 2003, R. Demina
Continue successful approach developed at Kansas State University (R. Demina) Si – the fastest growing technology in HEP Research done using onsite facilities Involve early grad and undergrad students Good training for HEP, solid state, semiconductor industry Work done for two projects (CMS, DØ 2b) with positive interference Success in 2b sensor development Silicon facility setup at UR supported by UR, dean’s funds CMS MOU funds DØ MOU funds Multipurpose CMS sensor probing DØ sensor QA Further development of rad hard technology for super LHC Silicon technology K-State UR Most equipment is in place Probstation is scheduled to be shipped on 7/24 DOE, July 23, 2003, R. Demina
Development of radiation hard Si ELMA • Demina, Korjenevski, Ginther • Run 2b rad hard Si development success Irradiation dose after 20fb-1 at r=1.8cm (L0 @D0) Vdepl <<700V (breakdown) HPK DOE, July 23, 2003, R. Demina
Si R&D for super LHC • R&D for the LHC detectors started in early 90’s • US CMS is planning for super LHC upgrades • Tracker is the first priority, new technology must be developed • Focus on • Rad hardness • Improved resolution • Reduced cost • We have done silicon development for one project (DØ 2b) • We have made significant contribution to the construction of three silicon detectors (CDF SVXII, DØ SMT2b, CMS TOB) • Have expertise, facility, contacts, interested collaborators at UCSB, FNAL • Possible route – join RD50, take advantage of the new approaches under development • Started initial discussions with RD50 leadership and groups • Testing new ideas (e.g. 3D column Si) with CMS electronics DOE, July 23, 2003, R. Demina
Conclusions • UR delivers highest quality • Technology, detectors, algorithms, physics, people • We have a well thought out plan for • DØ algorithms development and physics analysis • DØ and CMS detector construction • Transition from Tevatron to LHC physics • Technology development for future experiments • It’s a lean mean physics machine on its way to discovery • Keep it running DOE, July 23, 2003, R. Demina