Axel Drees, Stony Brook University RHIC II workshop, BNL, November 19, 2004 Decadal Plan PHENIX Decadal Plan Presented at open meeting and to PAC in Dec Exploit investments and opportunities at RHIC Detailed investigate of strongly interacting quark gluon matter Start spin physics program Start p-A program Reach beyond current capabilities: Detailed PHENIX upgrades program

Axel Drees PHENIX Experiment 2 central arms: electrons, photons, hadrons charmonium J/ ,  ’  e  e  vector meson   e  e  high p T       direct photons open charm hadron physics 2 muon arms: muons “onium” J/ ,  ’,      vector meson      open charm designed to measure rare probes: + high rate capability & granularity + good mass resolution and particle ID - limited acceptance Au-Au & p-p spin Discovery potential of PHENIX demonstrated in Run’s 1-4

Axel Drees Physics Beyond the Reach of Current PHENIX Comprehensive study of QCD at high T with heavy ion, p-nucleus, and pp high p T phenomena (PID - ,k,p- to p T ~10 GeV/c and  -jet, jet-jet tomography) electron pair continuum (low masses to Drell-Yan) heavy flavor production (c- and b-physics) charmonium spectroscopy (J/ ,  ’,  c and  (1s),  (2s),  (3s)) Extended exploration of the spin structure of the nucleon gluon spin structure (  G/G) with heavy flavor and  -jet correlations quark spin structure (  q/q) with W-production Transversity Dedicated p-nucleus program A-, p T -, x-dependence of the parton structure of nuclei Initial conditions for A-A: gluon saturation and the color glass condensate Provide key measurements so far inaccessible at RHIC in three broad areas: requires highest AA luminosity Requires upgrades of PHENIX and of RHIC luminosity requires highest polarization and luminosity

Axel Drees Central Magnet Region: -3.0 <  < 3.0 Spectrometer endcap VTX 1.2 <  < 2.7 barrel VTX |  < 1.2 NCC 0.9 <  < 3.0 TPC |  < 0.7 Provides displaced vertex & jet measurement over 2  TPC/HBD NCC VTX Displaced vertex: VTX: silicon vertex tracker Jet measurement: NCC: nose cone calorimeter TPC: time projection chamber Other detectors: HBD: hadron blind detector Muon trigger PID in west arm

Axel Drees RHIC Luminosity Increase Through e-Cooling ongoing luminosity development to  L  ~ cm -2 Electron cooling to  L  ~ cm -2 At constant beam intensity L in cm -2 or beam in ions year Integrated Au-Au luminosity recorded by PHENIX ~ 250  b -1 ~ 1.5 nb -1 ~30 nb -1 Increased luminosity will allow qualitatively new measurements and significantly more efficient operation of RHIC Luminosity increase through e-cooling: AA factor 10 pp factor 2-4 Au-Au luminosity development

Axel Drees PHENIX View of RHIC Upgrade Plans RHIC baseline program Au-Au ~ 250  b -1 at 200 GeV Species scan at 200 GeV Au-Au energy scan Polarized protons  150 nb -1 Full utilization of RHIC opportunities: Studies of sQGP with rare probes: jet tomography, open flavor, J/ ,  ’,  c,  (1s),  (2s),  (3s) Complete spin physics program Exploit p-A physics Extended program with 1 st detector upgrades: Au-Au ~ 1.5  b -1 at 200 GeV Polarized p at 500 GeV (start p-A program) Analysis of data on tape Near term detector upgrades of PHENIX ToFW, HBD, VTX Long term upgrades FVTX, TPC/GEM, NCC PHENIX upgrades 40x design luminosity for Au-Au via electron cooling Commissioning RHIC luminosity upgrade Near term: Base line Long term: full detector and RHIC upgrades Medium term: first upgrades

Axel Drees Outline For the Rest of My Talk: RHIC program and its running schedule Heavy ion program: What have we learned so far? What do we have on tape? What can we achieve with near term upgrades? What are the long term future perspectives? Spin physics program: Status of program Expectations for RHIC future Future p-A program

Axel Drees RHIC: The Worlds Prime QCD Laboratory RHIC is a dedicated accelerator with large flexibility. RHIC provides unique opportunity to study QCD in three broad areas ! Study of QCD at high T Heavy ion collisions with Au-Au at 200 GeV Energy (from 19.6 to 200 GeV) and species scans Accurate reference data from p-p and d-Au Exploration of the spin structure of the nucleon Polarized proton beams at high luminosity Dedicated p-nucleus program

Axel Drees Extraordinary Successful Program Since 2000 Heavy Ion Physics: Discovery Phase nearly completed Au-Au production run 250  b -1 at 200 GeV p-p and d-Au comparison runs at 200 GeV Exploratory energy scan 19.6, 62.4, 130, 200 GeV Species scan Cu-Cu in run 5 Spin Physics: Developing luminosity and polarization First production at 200 GeV in run 5 p-A program: Pilot run with d-Au at 200 GeV 24  b -1 Run 2: Au-Au & p-p  s nn = 200 GeV (Aug 2001 – Feb 2002) 1  b -1 Run 1: Au-Au  s nn = 130 GeV (June – Sept 2000) Run 3: d+Au & p+p  s nn = 200 GeV (Jan-May 2003) Rapid increase of integrated Au-Au luminosity 250  b -1 Run 4:Au-Au  s nn = 62.4 and 200 GeV p-p development run (Nov May 2004)

Axel Drees Projection into the “near” Future 27 cryo week scenario taken from PHENIX decadal plan Cu-Cu (3 nb -1 ) p-p development p-p at 200 GeV (  150 pb -1 ) p-p (or d-Au) at 62.4 GeV Au-Au at 200 GeV (  2 nb -1 ) p-p at 500 GeV (  300 pb -1 ) Constant effort running schedule taken from NSAC subcommittee report LHC Minimum program till 2012 well into LHC era

Axel Drees Much Left to do after 2012 Two running campaigns till FY2008 Only minimal program completed before LHC era Heavy ion program: only new data Cu-Cu Spin physics: minimum run at 200 GeV significant 2-6 below expectation p-A program not started Two additional running campaigns till FY 2012 A-A precision data only at 200 GeV and only for Au-Au p-p at 500 GeV with significance 3-9 below original goal p-A program not started New options with EBIS, e.g. U-U, not explored Long delay of spin physics program Increase in RHIC luminosity will expedite progress significantly

Axel Drees What have we Learned from A-A Collisions? Conclusions from first 4 years of RHIC running: Initial energy density 5-20 GeV/fm 3 well above QCD phase transition Multiplicity and large y data consistent with initial-state gluon saturation (CGC) Comparison of data to hydrodynamic models suggest early thermalisation Jet quenching: strong medium effects observed with penetrating probes Intermediate p T particle production hints towards quark recombination Little is known about this “strongly coupled plasma”: Hydrodynamic model fail to describe HBT source parameters No consistent description of jet quenching, lack of precision data Key observables not measured: dilepton continuum, thermal photons, charmonium states We apparently have created an ideal fluid of strongly interacting quarks and gluons RHIC needs to shift from discovery to exploration phase Answers summarized in the PHENIX white paper

Axel Drees Exploring the Strongly Interacting Plasma Basic plasma properties pressure, viscosity, equation of state, thermalization time & extent determine from collective behavior Other plasma properties radiation rate, collision frequency, conductivity, opacity, Debye screening length what is interaction  of q,g in the medium? need short wavelength strongly interacting probe transmission probability jet quenching via R AA, angular correlations etc Analog of hard x-ray probe of EM plasma Use penetrating probes:hard scattering processes electromagnetic radiation RBRC workshop Dec. 16/17: Strongly coupled plasmas: Electromagnetic, Nuclear and Atomic

Axel Drees On Tape: Thermal Photons Access to temperature of the system Experimental Challenge Expected signal ~ 10% Systematic error limited Prerequisites: High statistics Excellent knowledge of hadron decay background Precise reference for prompt component from pp thermal prompt Turbide, Rapp & Gale PRC (2004) Expectation: Data on tape 250  b -1 from run 4 Au-Au 200 GeV Establish method for future runs, e.g. Cu-Cu, Au-Au at lower  s

15 Medium Term: Low-Mass e  e   Pairs at RHIC Significant contribution from open charm R. Rapp nucl-th/ Strong enhancement of low-mass pairs persists at RHIC Only known channel sensitive to the chiral transition and thermal radiation Effect of quasi particle states in strongly interacting QGP Possible mass threshold near 2 GeV Shuryak, Zahed hep-ph/030726

Axel Drees A Hadron Blind Detector (HBD) for PHENIX signal electron Cherenkov blobs partner positron needed for rejection e+e+ e-e-  pair opening angle Dalitz rejection via opening angle Identify electrons in field free region Veto signal electrons with partner HBD concept: windowless CF4 Cherenkov detector 50 cm radiator length CsI reflective photocathode Triple GEM with pad readout Construction/installation 2005/2006  e + e -    e + e - S/B ~ 1/500 “combinatorial pairs” total background Irreducible charm background all signal charm signal Need Dalitz rejection (HBD) & charm measurement (VTX)

Axel Drees Medium and Long Term: Precise Charm Measurements Is there pre-thermal charm production? Does charm flow? Does charm suffer energy loss? Charm out to p T > 4 GeV/c Precision measurement Charm measurement requires precise vertex tracking Beauty measurement requires also highest luminosity Are there medium modifications for heavy quarks?

Axel Drees Vertex Tracker with Barrel and Endcaps Heavy flavor detection in PHENIX: Beauty and low p T charm via displaced e and/or  -2.7<  <-1.2,  |<0.35, 2.7<  <1.2 Beauty through displaced J/   ee (  ) -2.7<  <-1.2,  |<0.35, 2.7<  <1.2 High p T charm through D   K  |<0.35 VTX barrel |  |<1.2 Barrel silicon detector RIKEN: Hybrid pixel detectors developed at CERN for ALICE DOE: Strip detectors, sensors developed at BNL with FNAL’s SVX4 readout chip Completion by 2008 Forward silicon detector: “mini” strips (~0.1 x 1 m 2 ) R&D effort with FNAL initiated Expect ~1-2 year development Pixel Detectors (50  m x 425  m) at R ~ 2.5 & 5 cm Strip Detectors (80  m x 3 cm) at R ~ 10 & 14 cm FVTX endcaps 1.2<|  |<2.7 mini strips

Axel Drees On Tape: First J/  measurements Run 2 poor statistics Run 3 reference data from p-p and d-Au Run 4 higher Au-Au statistics Expect total of ~6000 J/  Measurement will remain statistics limited Coalescence model (Thews et al.) Absorption model (Grandchamp et al.) Statistical model (Andronic et al.) Run 2 final result Run 4 Au-Au J/  →ee min. bias (10% of statistics) J/  →  peripheral (>40%) (30% of statistics)

Axel Drees Many Open Issues Concerning J/  Production Is J/  suppressed? Latest lattice results indicate  cc screened only above 2 T c What is the screening length? New production mechanisms? Large  cc at RHIC Enhancement due to cc coalescence? New backgrounds from B-decays What is the baseline from p-p and p-A? Elementary production mechanism Shadowing and “normal” nuclear absorption Need accurate normalization to charm production Need high statistics measurement of multiple charmonium and bottonium states

Axel Drees Near and Long Term: Quarkonium Physics Expected quarkonium statistics from Au-Au runs 2008 and 2013 RHIC (1.5 nb -1 )RHIC II (30 nb -1 ) J/   ee  ’  ee   ee VTX J/  (  ’ )   38,000 (1400) 760,000 (28,000)     -trigger Need measurements with similar p T or x T reach in p+p, d+A, lighter systems Improved mass resolution with vertex tracker  →ee from 10 nb -1 Au-Au with and without VTX Full quarkonium program Requires electron cooling

Axel Drees High p T Phenomena in A-A Collisions at RHIC Future progress require more detailed studies: extend K, , p identification flavor tagging  -jet tomography Jet quenching: one of the most interesting discoveries at RHIC Baryon enhancement: modification of jet fragmentation in medium PHENIX

Axel Drees What do we have on tape concening hard scattering? High statistics data from Au-Au run 4      out to 20 GeV/c  -h correlations out to 10 GeV/c p,  p inclusive and h-correlation to p T  5 GeV all vs reaction plane Sufficient for next steps More jet PID measurements Follow up new ideas Most results from run 2 Expect significant new insight into interesting and rapidly evolving field E.Shuryak et al. Jet particle composition

Axel Drees Medium Term Upgrades: High p T Particle Identification PID upgrade: 1 st Aerogel detectors installed and commissioned in 2003 full detector completed MRCP based TOF detector prototype will be installed 2004 construction & installation 2005/2006 Combination of three PID detectors RICH with CO 2  th ~ 34 Aerogel Č,  th ~ 8.5 MRPC TOF  < 100 ps , K, p separation out to ~ 10 GeV/c coverage ~ 4 m 2 in west arm GeV/c most important PHENIX Au-Au 200 GeV

Axel Drees Medium Term: Expectation for “Run 8” 1.5 nb -1 Au-Au Detector improvements: High pT particle identification Larger jet acceptance in VTX Plus ~ 10 times more statistics Inclusive proton spectra out to ~10 GeV p-h correlations out to 10 GeV  -jet out to 10 GeV flavor tagging? vs reaction plane and centrality First handle on in medium jet fragmentation Data in modified and unmodified region Access to flavor dependence and q/g energy loss? Over limited kinematic region Bourrely & Soffer zz Baryon fragmentation functions:

Axel Drees Long Term: Rate Estimates for  -jet Tomography Rapidly falling cross section with rapidity: Assume ~ 1000 events required for statistical  -jet correlation RHIC II luminosity PHENIX acceptance (TPC & NCC) ymax  -p T (GeV) with TPC only for RHIC I  -jet tomography at RHIC requires RHIC II luminosity  and jet reconstruction in central region (-2 <  < 2) Run 4 estimated pt reach for RHIC II & TPC & NCC

Axel Drees Future PHENIX Acceptance for  -jet Measurement rapidity Prompt photons: central EMCal |y| < 0.35 forward NCC 0.9 < y < 3.0 (-3.0 < y <-0.9) Jet (charged): central TPC + VTX |  | < 1.2 forward silicon 1.2 <  < 2.7 (-2.7 <  <-1.2) Jet (energy): forward NCC 0.9 <  < 3.0 (-3.0 <  < -0.9)  coverage 2  Large acceptance for  -jet tomography: expect measurements out to E jet > 20 GeV Large acceptance for flavor tagging Limited acceptance for p – meson separation 4 GeV 10GeV

Axel Drees Status of Polarized Proton Program? First data: pQCD is a good reference   data: PRL 91 (2003) Need continuous development of luminosity and polarization 4 weeks run 2: L~250 nb -1  p  ~ 27%  p  4 L ~ days run 4: L~75 nb -1  p  ~ 40%  p  4 L ~ 1.9 A LL proof of principle: Significance factor smaller than goal Spin physics program just starting

Axel Drees What Will It Take to Make This Program Successful? A dedicated program of machine development A commitment to increase RHIC running time F A decade of only 27 weeks per year severely jeopardizes the spin program (the entire program) Detector upgrades VTX and  -tigger

Axel Drees Medium Term: Spin and pA Physics with VTX Measurement of gluon polarization by heavy flavor production Extended acceptance for  -jet Extracting gluon structure function in nuclei, shadowing gluon polarizationgluon structure

Axel Drees Probing Initial Conditions for A-A with p-A How does the CGC thermalize so fast? p-A collisions at forward rapidity Forward detector upgrades: NCC → 0.9 <  < 3.0 FVTX → 1.2 <  < 2.7

Axel Drees Foundations of Future PHENIX Physics Program Initial conditions for QGP formation CGC: p-A collisions, forward physics, large  -coverage Properties of strongly interacting QGP EOS: Collective behavior → advanced hydro calcuations Temperature: Thermal radiation → real and virtual photons Screening length: J/ ,  ’,  (1s),  (2s),  (3s) → resolution and acceptance Transport properties:  -jet and jet-jet → large acceptance and PID to 10 GeV/c Formation of Hadrons Creation of Hadrons: Hadronization → PID and correlations at moderate p T Origin of mass: Chiral Symmetry → Low mass dileptons Spin structure of the nucleon  G/G and transversity: 200 GeV pp running time &  -jet, jet-jet, heavy flavor  q/q: 500 GeV pp running time & W-trigger Structure of the nucleus A-, p T -, x-dependence structure functions: high statistics p-A running with different species

Axel Drees PHENIX view of RHIC Upgrade Plans RHIC baseline program Au-Au ~ 250  b -1 at 200 GeV Species scan at 200 GeV Au-Au energy scan Polarized protons  150 nb -1 Full utilization of RHIC opportunities: Studies of QGP with rare probes: jet tomography, open flavor, J/ ,  ’,  c,  (1s),  (2s),  (3s) Complete spin physics program p-A physics Near term detector upgrades of PHENIX ToFW, HBD, VTX 40x design luminosity for Au-Au via electron cooling Commissioning Long term upgrades FVTX, TPC/GEM, NCC Extended program with 1 st detector upgrades: Au-Au ~ 1.5  b -1 at 200 GeV Polarized p at 500 GeV (start p-A program) Analysis of data on tape PHENIX upgrades RHIC luminosity upgrade Near term: Base line Long term: full detector and RHIC upgrades Medium term: first upgrades

Axel Drees BACKUP

Model Predictions * compilation from the PHENIX Whitepaper

Axel Drees What can we conclude? Fast local equilibration within time t= fm/c and density GeV/fm 3 ! Confidence about the latent heat is premature. The exact viscosity limit is still not constrained. Softest point should increase HBT observed lifetime (not seen).

Axel Drees Improved Muon Trigger Enhanced first level muon trigger: p-Cut: U-Tracker + D-Tracker Timing:D-Tracker Project Schedule Recently proposed to PHENIX collaboration Proposal to NSF in FY05 Estimated cost $2 M Construction 2005/2006 Completed for first 500 GeV pp run First level trigger for high luminosity Increased background rejection W production in p-p 500 GeV/c Upsilon production with RHIC II luminosity p muon Muons from Ws Muons from hadrons U-Tracker decays  Muon from W D-Tracker

Axel Drees Nosecone Calorimeter (NCC) Forward physics with PHENIX Large acceptance calorimeter EM calorimeter ~40 X/X o hadronic section (1.6   ) Tungsten with Silicon readout Extended physics reach with NCC Extended A-A program high p T phenomena:  0 and  -jet χ c → J/  +  Small x-physics in p-A Scope Recently proposed to PHENIX collaboration New expert groups join R&D (MSU, Triest, Prag) Construction FY08 – FY09 W-silicon sampling calorimeter 20 cm 0.9 <  < 3.0 More details in K. Barish’s talk