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Mark Oreglia Activities in the EFI HEP Group. OPAL ATLAS (Muon Collider/Beamline Instrumentation)* International Linear Collider * ICAR project. OPAL: 1985-2005. There was much more hair around here in 1987 … when we built OPAL’s Presampler Barrel
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Mark Oreglia Activities in the EFI HEP Group OPAL ATLAS (Muon Collider/Beamline Instrumentation)* International Linear Collider * ICAR project M. Oreglia/NSF Site Visit
OPAL: 1985-2005 • There was much more hair around here in 1987 … when we built OPAL’s Presampler Barrel • Shows the stress of reductions in NSF funding • What Pilcher did not cover: • Chicago searches • b ID and B physics • Tau physics • Exotic Higgs bosons • LEP-wide Higgs combo M. Oreglia/NSF Site Visit
Searches for Higgs Bosons • Chicago has been involved in the OPAL Higgs searches since day-1: • Oreglia authored first OPAL Higgs search paper (1990) • Presented first LEP search summary at Neutrino ‘90 • Oreglia, Strom, Roney: dilepton channel • Hocker, Oreglia: tau channel and MSSM strategy • Tau channel sensitive to new physics • Contributed to flavor-independent Higgs limit • Nguyen, Merritt: first decay-mode independent LEP search (1991) • Coverage of low mass region filled a gap and is still the best limit M. Oreglia/NSF Site Visit
From Hogan’s Flavor-Independent Paper • LEP-1 analysis from 1991 • set limits to mH=0 • tagged recoil against: • Z → ee, mm • Z → nn • still best low-mass limits M. Oreglia/NSF Site Visit
Nonstandard Higgs Bosons • Exploration of more general 2HDM led to “photonic Higgs” LEP industry (Oreglia, Turcot) • First paper in 1993; followed by other 3 LEP collabs • Led to development of better photon ID tools • Promoted better investigation of theory space • Expanded fermiophobic 2HDM • Higgs triplet models • Final analysis of all LEP data: • OPAL limit is still the best, so there! • Oreglia has combined the LEP results … limit to 109 GeV • Inclusion of WW, ZZ channels in process (publication in 2005) • Participation in MSSM analysis → CP-violating model • Only OPAL has limits on this now-popular model M. Oreglia/NSF Site Visit
Results from OPAL Photonic Higgs Search M. Oreglia/NSF Site Visit
b ID and B physics • Kroll: chaired lepton ID working group; improved b ID for first Rb analyses • Glenzinski, Hocker: applied first likelihood + ANN techniques to b ID … platform for W mass • Bellrive extended this to charm and got improved Vcs and RWc • Also resulted in single-top production search and limits on FCNC • Amaral, Oreglia revisited measurement of the semileptonic decays of the b quark into P-wave charmed meson D** states M. Oreglia/NSF Site Visit
BR(BD**ℓ ) • disagreement among experiments on branching ratios into the two narrow states (D1 and D2*) and whether two predicted broad states exist • difficult because the D** decay products must be identified in the core of a jet. • Advances in data analysis techniques (especially b-tagging and particle ID) warranted a repeat measurement, and the new analysis has obtained much better results compared to the previous OPAL publication. • It was nice to measure something that exists M. Oreglia/NSF Site Visit
Other Chicago Contributions • Heavy leptons: Merritt, Anderson, Redmond, Schappert • Excited leptons: Teuscher, Oreglia, Zhao • Tau Physics: Evans, Pilcher,Tecchio • Instrumentation: • Eric Torrence (with Mike Hildreth) came up with the idea of designing a beamline spectrometer to check the LEP energy calibration … 10 MeV precision • Luminometer: • DAQ electronics designed/built at EFI (Anderson, Pilcher) • Si prototyping and construction: Tecchio developed 5 mm metrology • lumi testbeam organized by Chicago: Oreglia, Evans, Wagner, Hart, Strom • Tools: • Bellerive, Kroll, Glenzinski, Hocker: vastly improved lepton, b- and tau tagging using likelihood techniques incorporating neural network elements • Evans, Tecchio, Pilcher: Kaon ID in multihadron modes • Oreglia, Turcot: improved conversion ID … package used in all post-1995 photon analyses • Amaral, Oreglia: improved b-ID in multi-jet environment • Merrett, Anderson: major fix in heavy lepton MC • Strom, Wagner; Hart, Pilcher; Oreglia: luminosity analysis M. Oreglia/NSF Site Visit
Exotics – Phase II • LEP exotic Higgs activities have been reborn in Geneva: the CP-violating and non-standard Higgs WG • Application to TeVatron, b-factories, LHC and LC • Making sure we cover all the bases • Just like the yellowbook era of 1990 … new stuff M. Oreglia/NSF Site Visit
NSH: ATLAS Coverage • It is becoming increasingly apparent that there are non-minimal models which have theoretical advantages over MSSM: • Strong EWSB • MSSM+extra singlets = Minimal Nonminimal SSM… MNSSM • Higgs not of this earth: Extra Dimension models • Higgs as a pseudo-Goldstone boson: Little Higgs • 2HDM and triplets: fermiophobic Higgs • … and the list is growing • Problem: adequately covering the phase-space • Are there topological solutions? • What signatures yield fastest unraveling • K-factors still not under control M. Oreglia/NSF Site Visit
ATLAS Activities • Rapidly growing Chicago analysis activity • Gupta and Merritt paved the way • Farbin and Hurwitz advancing SUSY analyses • Martina moving to CERN; devoting to SUSY Emiss analysis • Now primary activity for Oreglia • With Matt Wood: explored calorimeter cell-weighting within Athena • New optimizing event definition for specific processes • Since 2000: working with Elizabeth Richter-Was on covering exotic SSB searches • But aversion to using inadequate older simulations • Going state-of-art has long learning curve these days • Co-coordinator now in CPNSH M. Oreglia/NSF Site Visit
More prosaic: Early studies of calorimeter cell weighting schemes • Work done 2002-3 with student Matthew Wood • Study of jet energy resolution as function of calorimeter cluster weights • The problem: calorimeter calibrated to EM energy scale, and hadron calorimeter is not compensating • We sought to minimize resolution with weights defined for h zones … used full ATHENA framework (ouch!) M. Oreglia/NSF Site Visit
Chicago SUSY Emiss Activity • Gupta, Farbin, Hurwitz very active in crafting second-generation SUSY Emiss analysis • Using the real tools … not old noiseless fortran • Well matched to our work on jet definition and calibration • Farbin has been successful in getting our own GRID production underway • Looking at Meff = ETmiss + ETjets • Have generated good statistics samples now • Seeing big differences from DC1 • Starting to explore: • Resolution … testbeam analysis • Looking for better variables/objects M. Oreglia/NSF Site Visit
My own “pet” project of the moment: Hard, but Interesting physics … Higgs or Strong EWSB or ??? • Challenging process for detector • 2 high-pT forward jets + WW or ZZ in central region • problem background from gg→ttg • Recent progress … discovery of discriminating variables (Dytag, etc) • Can optimizing particle flow help out here? • Can PF lead to better discriminating variables or likelihood? • Can jj mass resolution be optimized by PF to differentiate W or Z? • And this study good for LC too • Therefore, just beginning to study calorimeter clustering and PF matching to tracker with 2 undergrads (Jim McNeur and Tien-tien Yu) M. Oreglia/NSF Site Visit
Muon Collider Interlude • During 2001-2004 I spent a fraction of my time studying Muon Collider physics and beamline instrumentation • Work conducted with Kwang-Je Kim and postdoc Kara Hoffman using funding from State of Illinois • The problem: instrumentation that can survive the extreme environment in a muon ionization channel M. Oreglia/NSF Site Visit
Beam Profile Monitor Ideas • 1st round: concentrated on bolometric concept – attached to liquid-H absorber vessel • Developed graphite, nickel, etc, devices • Refurbished vacuum deposition system; built prototypes • Harold Sanders & Mircea Bogdan developed electronics • Set up pulsed Xe and Ar-laser beam simulators; later beam tests • Trained 5 undergrads (and Kara ) • But: evident now that MuColl technology far in future, and Kara had the idea to try dirty CVD diamond • Hypothesis: near-heatsink grade CVDD might perform adequately in intense beams and survive • Result: it worked; prototypes built and tested • FNAL beams division is producing some now M. Oreglia/NSF Site Visit
Linear Collider Activities • When it became clear that MuColl not feasible, LC activity was ramping up … Snowmass 2001; HEPAP • Chicago hosted ALCPG January 2002 Workshop • Jim Brau and myself suceeded Baltay/Grannis as ALCPG co-chairs • Blucher, Kim on Exec Ctte • Kim on US SG • LC Steering cttes formed • MJO edited US “scope” paper • MJO co-wrote the ILC scope paper • MJO+Dawson: ARNPS 2004 review on LC • Jim & I focusing on getting detectors better defined and important R&D to a higher level • DISCLAIMER: LHC activity has higher priority right now; for moment asking just for LC travel M. Oreglia/NSF Site Visit
Remainder of My Talk:Why LC Detector $ Now; MJO Projects • ILC/FALC schedule call for physics starting 2015 !!! • Not credible, but they have reasons for staying with this for now • Strong reasons to urge startup while LHC still online (2020?) • With that timeline in mind, many feel it is premature to spend R&D money on detectors now • I don’t, so let me explain why • LC detectors have very clear physics missions • They require state-of-the-art 2-10 • Repeat: not LHC technology; not LEP technology The following are adapted from a recent talk at MDI/SLAC M. Oreglia/NSF Site Visit
3 Archetype Physics Topics • Light Higgs -- tracker • Best recoil mass resolution in Z-> dileptons • Strong EWSB -- calorimeter • Important to look at WW scattering • W/Z jet separation crucial • Some SUSY scenarios -- hermeticity • Cosmology “benchmarks” summarized: • “bulk” -> cc annihilation -> smuon/selectron • “coannihilation” -> c-stau annihil. -> staus • Low angle backgrounds M. Oreglia/NSF Site Visit
Momentum Resolution • e+e-gZHgllX • Golden physics channel! • Zgmm BR = 3.4% • d(1/p) = 7 x 10-5/GeV • 1/10 LEP !!! • goal: dMmm <0.1x GZ • dMHdominated by beamstrahlung M. Oreglia/NSF Site Visit
Impact Parameter • dd= 5 mm Å 10/p(GeV) mm • 1/3 SLD !!! • excellent flavor tagging capabilities for charm and bottom quarks • Need exceptional tagging for reducing combinatorial background in multi-jets ... • Charge assignment • Asymmetry measurements • (measurement of Higgs BRs not so sensitive!) • The big question: inner VTX radius • No simple answer – physics reach gains with lever arm and background suppresion, esp low momentum particles • … thus, low MS, small radius is essential • Needs more validation, but we are talking 1.5 cm radius! • Instrument lifetime issue M. Oreglia/NSF Site Visit
(Jet) Energy Resolution • dE/E = 0.3/ÖE(GeV) • <1/2 LEP !!! • DMDijet ~ GZ/W • separation between e+e-gnnWWgnnqqqq and e+e-gnnZZgnnqqqq M. Oreglia/NSF Site Visit
Particle Flow • reconstruction of multijet final states • e+e- H+H- tbtb bqqb bqqb • Emphasis on combined systems now • System compataibility means fine granularity in calorimeters (1 cm2 !!!) • Digital mode possible, if backgrounds controllable M. Oreglia/NSF Site Visit
Hermeticity • hermetic down to q = 5 mrad • Important physics with missing energy topologies (SUSY , extra-dim, Higgs, ...) • Background issues • Ability to veto low-pT particles • Crossing angle optimization • Excellent physics motivation: SUSY-stau M. Oreglia/NSF Site Visit
IR-Related Issues • Good measurements in the low-angle region • Need to make pT cuts for physics analyses • Need to mask and reduce occupancies in low angle region • Need convincing? See Bambade’s summary of X-angle mtg • Beam-beam interaction • broadening of energy distribution (beamstrahlung) • ~5% of power at 500 GeV • backgrounds • e+e- pairs • radiative Bhabhas • low energy tail of disrupted beam • neutron “back-shine” from dump • hadrons from gamma-gamma M. Oreglia/NSF Site Visit
IR Issues pairs Hits/bunch train/mm2 in VXD, and photons/train in TPC M. Oreglia/NSF Site Visit
Beam Energy • need to know <E>lumi-weighted • Some analyses require better than 0.1% • techniques for determining the lumi-weighted <ECM>: • energy spectrometers • Bhabha acolinearity • Other possibilities : • gZ, ZZ and WW events; use existing Z and W mass • utilize Bhabha energies in addition to Bhabha acol • m-pair events; use measured muon momentum • 200 ppm feasible; 50 ppm a difficult challenge Top-mass: need knowledge of E-spread FWHM to level of ~0.1% M. Oreglia/NSF Site Visit
Crossing Angle M. Oreglia/NSF Site Visit
There are currently 3 Detector Concepts • The WorldWide Study is working on a plan: • organization of effort • benchmarking performance • cdr/tdr’s • selection • 3 concepts are materializing: • The TESLA concept: TPC-tracker • Silicon tracker + calorimetry (SiD) • new large magnetic volume concept (Global Large Detector, GLD) • Rethinking as new information available M. Oreglia/NSF Site Visit
Comparison of 3 Concepts(thanks to Y. Sugimoto) • Very large R • Jet chamber or TPC • Scintilator/W-Pb-Fe • Si tracking and ECAL • Small R • Smallest granularity • Moderate R • TPC tracker • SiW ECAL M. Oreglia/NSF Site Visit
Snowmass 2005 • The ALCPG and, separately, ILC will meet at Snowmass this summer • Crucial steps towards detector definitions and CDRs • Real chance to optimize integrated detector design for PF • Essential studies of Machine-detector interface • 700 participants expected, with about 50% non-US M. Oreglia/NSF Site Visit
Summary of MJO LC Future • 1st priority: getting global detector R&D on track • 2005: concentrate on administrative role (travel money) • Detector R&D activity: detector optimization for PF • Working with undergrad to do this for SiD concept • Linking this to what we learn from PF studies for ATLAS • Since ATLAS takes priority now, I see this as the responsible way to contribute to LC (unless a postdoc can eventually be taken on for LC activity) • I have also worked with Jose Repond (ANL) on RPC hadcal • Undergrads Abby Kaboth and Steve Olmschenk built/tested prototypes and CR telescope/tracker • Abby identified several problems with the design: • I’d like to continue participating on CALICE prototype and beamtest … perhaps subcontract to build FE electronics in our e-shop M. Oreglia/NSF Site Visit