PHENIX Physics Agenda and Detector Upgrades Axel Drees, SUNY Stony Brook QCD at RHIC 12/8/2000 Overview Completion of the PHENIX “baseline” program heavy ion and spin physics program completion of PHENIX detector running plan for the next 5 years Physics beyond the reach of the baseline detector heavy ion physics program spin physics program proton-Nucleus Program Detector upgrades improvements of existing detectors concept for additional detector systems technical solutions cost guesstimate and timelines

Overview: PHENIX Physics Program for the Next Decade first phase complete initial heavy ion and spin physics program complete experimental setup enhance detector capabilities second phase: heavy ion physics: systematic study of high T, r QCD address important issues not or only partially covered by original detector lepton pair continuum below and above the f charm and bottom production Drell-Yan continuum upsilon spectroscopy: Y(1S), Y(2S), Y(3S) QCD energy loss , g-jet correlations and more spin structure of the nucleon: enhance capabilities, increase kinematical acceptance W-boson production heavy flavor production inclusive jet production gluon distribution function transversity spin effects in fragmentation proton-nucleus physics exploit the unique features of RHIC quark and gluon content of nuclei parton density at small x parton energy loss as fct of (A, pt, x) hard diffractive processes Axel Drees 22-Sep-18

PHENIX Heavy Ion Program Axel Drees 22-Sep-18

PHENIX “Core” Program designed to measure penetrating “rare” probes central detector: vector mesons w, f, J/y -> e+e- photons high pt pions po, p+, p- muon arms: vector mesons J/y, U -> m+m- combined central and muon arms: charm production DD -> em focus on electromagnetic probes well matched to requirements of spin physics program Axel Drees 22-Sep-18

PHENIX configuration for 2000 West Arm tracking: DC,PC1 electron ID: RICH, EMCal photons EMCal East Arm tracking: DC, PC1, TEC, PC3 hadron & electron ID: RICH,TEC, TOF, EMCal photons: Other Detectors vertex & centrality: ZDC, BBC, partially equipped systems MVD, MuID initial physics program: global observables identified hadron spectra inclusive high pt ~ 4 GeV/c spectra inclusive electrons ~ 3 GeV/c Axel Drees 22-Sep-18

Preliminary Physics Results identified hadrons: p- K- p+ K+ p p e- e+ inclusive h- and p0: inclusive electrons: Axel Drees 22-Sep-18

Enhanced Setup for Next Run 2001-2002 West Arm tracking: DC,PC1, PC2, PC3 electron ID: RICH, EMCal photons East Arm tracking: DC, PC1, TEC, PC3 hadron& electron ID: RICH,TEC, TOF, EMC photons: EMCal Other Detectors Vertex & centrality: ZDC, BBC, MVD South Arm tracking: MuTr muon ID: MuID full heavy ion program and major fraction of spin program: vector mesons f and w J/y production direct photon out to 10 GeV (Au-Au) or 30 GeV (pp) high pt inclusive out to 10 GeV jet-like angular correlation Axel Drees 22-Sep-18

2003 and Beyond additional detector upgrades: tracking: east arm PC2 electron ID: east arm TRD/TEC PC2 TRD/TEC North Arm tracking: MuTr muon ID: MuID DAQ and Trigger de-multiplexing L2 trigger upgraded EVB high statistics studies with 2 1027 cm-2s-1 Au-Au and 2 1032 cm-2s-1 pp: Au-Au p-p increase pt range to 20 GeV direct g to 40 GeV precision J/y and y’ high mass Drell-Yan pairs first data on Y bottom production g-jet correlations W-boson production Axel Drees 22-Sep-18

Upgrades of Baseline Setup significantly enhance detector performance at moderate effort and cost PC2 east: $500k in beam experience: redundant (3d) tracking needed to suppress no-vertex background vital for high pt > 6 GeV/c and jet-jet correlations TRD/TEC: $700k extend electron identification to pt > 6 GeV p / K separation above 2 GeV/c ?? Axel Drees 22-Sep-18

Other Possible Baseline Upgrades DAQ and Trigger partially funded + 800k increase rate capability as luminosity increases includes needs for second phase upgrades anode readout for MuTr $3,000k issue: tracking at highest multiplicities need to wait for in beam experience TRD/TEC for west arm $1300k extended electron identification improved momentum resolution pre-shower detector increase radiation length  improve energy resolution longitudinal segmentation  improve hadron rejection higher granularity  improve g /po separation Axel Drees 22-Sep-18

Proton-Nucleus Physics has been discussed in length at previous workshop there are no p-A data at s = 200 GeV has been essential in understanding “non-exotic” multi-body effects: Strangeness enhancements J/Y production/absorption Gluon shadowing  FNAL E866  MMN  MMS+MMN  MMS  Central example: Drell Yan pair acceptance and statistical errors for 2x 15 weeks pp and pd running Axel Drees 22-Sep-18

assume ~22 weeks/year heavy ions and ~10 weeks/year polarized protons Possible Run Plan assume ~22 weeks/year heavy ions and ~10 weeks/year polarized protons Year-2: (2001-2002) Au+Au, crude p-p comparison run first look at J/Y production, high pT first polarized proton run Year-3: (2003) High luminosity Au+Au (60%) of HI time High luminosity light ions (40%) of HI time Detailed examination of A*B scaling of J/Y yield DG/G production run with polarized proton first p-A measurements Year-4: (2004) p-d/p-p comparisons baseline data for rare processes W-boson production with polarized protons Drell-Yan study in p-A Year-5: (2005) “Complete” p-A program with p-Au energy scan Systematic mapping of parameter space Axel Drees 22-Sep-18

Beyond the PHENIX Baseline Program profit from investments made, exploit further possibilities to measure rare processes: electromagnetic radiation and hard scattering Heavy Ion Physics shift of focus from establishing the existence of QGP and first studies of its properties to systematic study of QCD high T, r focus on key measurements not or only partially addressed by original PHENIX setup: pair continuum below and above the f charm and bottom production Drell-Yan continuum upsilon spectroscopy, Y(1S), Y(2S), and Y(S3) QCD energy loss via g -jet angular correlations for these measurements the PHENIX central and muon spectrometer are essential but not sufficient ! Axel Drees 22-Sep-18

Continuum Lepton-Pair Physics resonances addressed by original PHENIX setup pair continuum not yet accessible at RHIC large excess of continuum radiation observed in heavy ion collisions at CERN has been attributed to melting of resonance's, dropping masses  look at vector mesons ,  however, recent theoretical discussion focuses again on thermal radiation anomalous lepton pair production in pp collisions not excluded excluded only within ~15-30% systematic errors at low energies completely open at higher energies! q q e, m - e, m + Axel Drees 22-Sep-18

Electron Pairs at Low Mass in p-Be collisions well described by neutral meson decays within 15-30% systematic errors Dalitz decays: e+e-  e+e-   e+e- vector mesons: r e+e- w e+e- f e+e- anomalous lepton pairs at s = 200 GeV?? enhanced e+e- production in Pb-Au collisions: at CERN SPS threshold near 2mp different spectral shape no r resonance structure 0.25 < m < 0.75 GeV D/S ~ 2.6  0.5  0.6 Axel Drees 22-Sep-18

Radiation from Hot and Dense Matter pp-annihilation contribution pp resonance structure: r-meson formfactor described by vacuum values mr = 770 MeV Gr = 150 MeV characteristic shape not observed in data solution: modification of meson properties in dense matter melting  resonance dropping  mass (Brown-Rho scaling) p r* g* e- e+ data seem to require modification of meson properties related to chiral symmetry restoration Axel Drees 22-Sep-18

More Recent Calculations data stimulated more than 100 theoretical paper origin of continuum radiation not yet clarified recent new development: thermal radiation from QGP (Schneider & Weise) a lot of interesting physics in lepton pair continuum Axel Drees 22-Sep-18

Experimental Challenge huge combinatorial pair background due to copiously produced photon conversion and Dalitz decays : need rejection of > 90% of  e+ e - and po   e+ e - active recognition and rejection of background pairs photon conversion  e+ e - Dalitz decays po   e+ e - false “combinatorial pair” In PHENIX: combinatorial background factor > 1000 larger than signal Note: resonances f and w can be measured due to excellent mass resolution Axel Drees 22-Sep-18

Dalitz and Conversion Rejection mass of virtual photon small  small pair opening angle need tracking at low momentum and sensitivity to opening angle detector requirements: tracking in low or field free region to preserve opening angle tracking and electron ID over 2x (25+90+25) degree  Df ~ 2p central arm ~ 200 MeV momentum cut off ~ 70% of pairs one track > 200 MeV 2nd track < 200 MeV can not be reconstructed in central arms possible mode of operation Axel Drees 22-Sep-18

Direct Radiation vs Open Charm NA50:  -pairs at intermediate masses (1 < m < 3 GeV) M.C. Abreu et al, Nucl.Phys A661 (99) 538c R.Rapp & E.Shuryak, Phys.Lett B473 (2000) 13 thermal radiation (Ti ~220 MeV) q q m - m + or open-charm enhanced by factor ~3-4 Question: can PHENIX baseline pin down charm x-section accurate enough? via inclusive e,m and ee, mm, em pairs Axel Drees 22-Sep-18

Precision Vertex Tracking to Detect Charm physics interest in charm and bottom production charm and bottom decays compete with thermal pair radiation charm can be produced thermally  charm enhancement probably not at CERN, but maybe at RHIC energies best reference for J/y and Y production once charm and bottom are known  access to Drell Yan continuum displaced vertex distinguishes prompt electrons (thermal) form decay electrons (charm and bottom) possible solutions to reduce effect of multiple scattering: high pt cut move first detector as close to beam pipe as possible m ct  eX GeV mm % D0 1865 125 6.75 D± 1869 317 17.2 B0 5279 464 5.3 B± 5279 496 5.2 ct Au e D easy to achieve >20 mm tracking resolution issue: multiple scattering in first detector layer Axel Drees 22-Sep-18

Measurement of Displaced Vertex toy detector model: 2x 2p silicon pixel tracking layers standard detectors with 50x425 mm2 a) R ~ 2.5 cm srf ~ 15 mm X/Xo ~ 1% s ~ 115 mm b) R ~ 10 cm ditto PYTHIA simulation of D mesons for s = 200 GeV track decay electrons simulate multiple scattering in layer a) simulate detector resolution pt cut of 750 MeV track back to vertex tracking resolution in rf: detector: sd ~ 16 mm mult. scattering: ms ~ 28 mm occupancy of inner layer < 1% } sd ~ 32 mm (at 1 GeV/c) Axel Drees 22-Sep-18

Study for Decay Electron Detection displacement to vertex in x-y projection decay electrons retrieve decay length with multiple scattering with detector resolution prompt electrons (same electrons but tracked to decay vertex) point back to vertex within 100 mm what works for D’s definitely will work for B’s given sufficient luminosity Axel Drees 22-Sep-18

Upsilon Spectroscopy original PHENIX capability: luminosity upgrade to 8 1026 cm-2s-1 or 8 1027 cm-2s-1 muon spectrometer accumulates ~ 16000 Y per 22 weeks central spectrometer accumulates ~ 2000 Y per 22 weeks improved momentum resolution in central spectrometer (shown later in this talk) north muon arm: sm ~ 190 MeV south muon arm sm ~ 240 MeV 22 week of Au-Au at 2 1026 cm-2s-1 total of ~ 400 Y decays (~ 1/10 in central arms) CDF data ~ 1000 Y PHENIX comparable to CDF: 2000 Y sm ~ 40 MeV Axel Drees 22-Sep-18

Jet-Quenching and QCD Energy Loss Suppose we find indications for jet quenching at RHIC next step: gain detailed understanding of QCD energy loss systematic studies of many questions: How accurate can we measure dE/dx ? How does dE/dx depend on x? How does dE/dx depend on pt? Do gluons lose more energy than quarks? What is the flavor dependence of dE/dx? Is there dE/dx in cold matter? experimental tools (rare processes): g - jet correlations jet - jet correlation flavor tagged jets tagged gluon jets ( K / p comparison) centrality and A dependence p-A and p-p comparision upgraded PHENIX detector well suited to address these issues requires highest possible luminosity Axel Drees 22-Sep-18

Spin Physics Program Recall: spin crisis of nucleon was discovered by extending kinematical coverage of original EMC measurement Increase kinematic coverage and measure W boson production isolation cuts on leptons central arm tracking: Df = 2p, D= 1 muon arms: forward calorimeter heavy flavor production precision vertex tracking to tag decay electrons jet production large acceptance tracking & momentum measurement gluon distribution function g - jet angular correlations transversity and spin effect in fragmentation enhanced tracking acceptance Detector upgrade requirements: Df = 2p, D= 1 precision vertex tracking forward calorimetry detector requirements similar to those from heavy ion program Axel Drees 22-Sep-18

Lepton Isolation Cuts Isolation cut: Jet lepton count activity around lepton distance of lepton from jet axis significantly enhances: heavy flavor tagging W  l  Drell Yan process technical solution: vertex tracking for central arms forward calorimeter for muon arms background Jet lepton heavy flavor jet Axel Drees 22-Sep-18

Jet Reconstruction with Charged Particles Only Kt Jet algorithm (hep-ex/0005012) DR sE/E only charged particles 0.08 30%   1 0.1 30% detector resolution (20%) 0.1 36% ktjet PYTHIA PYTHIA: QCD JET at s = 500GeV (pt > 20GeV) all particles   f = 2 p perfect sE jet reconstruction with ~ 40% sE/E feasible Axel Drees 22-Sep-18

Detector Requirements enhanced spin and heavy ion physics program addressed by one multi-detector detector system: vertex spectrometer around beam pipe precision vertex tracking with large acceptance Df = 2p and Dh =  1 ~30 mm single track resolution reasonable momentum resolution (sp/p ~ 3-4% p) electron identification p < 1 GeV for Dalitz rejection e /  ~ 50 flexible magnetic field configuration no field in vertex region for Dalitz rejection high field for high pt physics high rate capability Au-Au L ~ 8 1027 cm-2s-1 p-p L ~ 2 1032 cm-2s-1 Axel Drees 22-Sep-18

PHENIX Vertex Spectrometer: Scenario A “last nights sketch” central arm acceptance  22o  D ~ 0.7  20 cm IR region magnet coils micro pad chamber 1 m forward calorimeter Silicon Pixel layer 3 15 cm layer 2 7.5 cm layer 1 3 cm HBD beam axis and vacuum pipe hadron blind detector 1 m 40.4o  ~ 1 for  10 cm IR region Scenario B: replace HBD by TPC (or TEC) Axel Drees 22-Sep-18

Vertex Spectrometer Silicon Pixel Detectors Hadron-Blind-Detectors 3 layer system (?) Df = 2p and Dh =  1 standard pixel devices 50x425 mm2 contacts with LHC developments for ALICE and NA6i possible new collaboration with CERN (other options D0 or CMS, ATLAS) Hadron-Blind-Detectors proximity focusing He-Cherenkov counter CsI based photocathode GEM based readout “historical” R&D by Stony Brook group new collaboration at Weizmann Institute on CsI & GEM interest to collaborate with BNL instrumentation Micro Pad Chambers MWPC with pad readout further development of existing PHENIX pad chambers LUND, Vanderbilt …. Forward “Nose-Cone” Calorimeter lost of experience within PHENIX DAQ and Trigger ??? new inner magnet coil Axel Drees 22-Sep-18

Modified Central Magnet Configuration add second - inner - coil foreseen in PHENIX magnet design Three field configurations + new field 0 original configuration + - new field reversed polarity 0 field along beam axis ++ new field same polarity factor ~1.7 increased Bdl Axel Drees 22-Sep-18

Field Integral of New Magnet System Two future operation modes of PHENIX: +- field free region out to 50 cm sensitive to pair opening angle essential for pair continuum measurement ++ increase field integral by factor 1.7 increased momentum resolution important for high pt physics Axel Drees 22-Sep-18

Momentum Resolution with Inner Tracking momentum resolution with new field configuration and inner tracking +- configuration: similar to original setup ++ configuration: improved by factor ~3.5 silicon tracking only ( 3 point estimate) sp/p ~ 0.03 p sE/E ~ 40% for 20 GeV jet Axel Drees 22-Sep-18

Proton-Nucleus Physics Program Significant fundamental interest beyond AA comparison run motivation discussed in detail at previous workshop Issues to be addressed quark and gluon structure of nucleus parton density at small x propagation of partons trough nuclei hard diffractive processes standard tools di-leptons from Drell-Yan process prompt photons g - jet and jet - jet coincidences heavy quark production similar requirements like heavy ion and spin program to fully exploit RHIC’s unique opportunities additional equipment to tag forward going baryons (upgraded ZDC’s and Roman Pots) extend muon acceptance to forward angles to extend x2 coverage below 10-3 Axel Drees 22-Sep-18

Detector Upgrades for p-A Physics Roman Pots and ZDC forward muon spectrometer magnet Tracking chamber Axel Drees 22-Sep-18

Summary: Cost Guesstimate Based on: detectors build by PHENIX, experience with technology, or similar detectors build elsewhere 30 - 75% contingency, depending on stage of design and our knowledge of the technology baseline upgrades: PC2 east 500 k TRD east 700 k DAQ&Trigger 800 k muon anode electronics 3000 k TRD/TEC west 1300 k 6300 k vertex tracking system magnet 700 k silicon pixel 12000 k HBD (or TPC) 17000 k micro Pad chamber 3000 k forward calorimeter 2000 k 34700 k special p-Nucleus upgrades ZDC & Roman Pots 550 k forward muon spect. 3000 k 3550 k total: ~ $45 M R&D mostly silicon pixel & HBD (or TPC) $3-4 M over next three years (FY02 - FY04) Axel Drees 22-Sep-18

Summary: Timeline 2001-2002 south muon arm all central arm electronics Au-Au PC2,PC3 West first polarized p-p 70% MVD start R&D 2003 north muon arm high-LAu-Au PC2 east high-L light ions TRD/TEC east polarized p-p complete MVD first p-A continue R&D 2004 complete R&D pp/pd comparison Conceptual Design Report high-L pol. p-p ZDC & roman pots forward muon spectrometer 2005 upgrade construction p-A program energy scan 2006 upgrade construction & first polarized p-p installation & Au-Au 2007 - 2010 enhanced heavy ion & spin physics program Axel Drees 22-Sep-18