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RNC and Theory Groups input to National LRP for the next 10+ years. presented by Grazyna Odyniec. goal of this effort. Three meetings of RNC and Theory Groups to discuss and identify: areas of science that are of general importance to our program
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RNC and Theory Groups input to National LRPfor the next 10+ years presented by Grazyna Odyniec
goal of this effort • Three meetings of RNC and Theory Groups to discuss and identify: • areas of science that are of general importance to our program • areas of particular importance or sensitivity to our program • Goal:make significant contributions to the discussions at the November Town Meeting(s) in the area of greatest importance to us • LRP Berkeley, May13, 2006
physics program: testing QCD with experiment QCD strongly interacting matter Berkeley, May13, 2006
physics program: testing QCD with experiment QCD strongly interacting matter • QCD in hot and dense environments: • RHIC top energy: heavy flavor program, jets (g-jet) 5-10 yr. • ALICE at 5.5 TeV: wQGP ? hard probe program 5-10 yr. • energy scan (2-20 GeV): baryon rich physics program 5-15 yr. (RHIC low energy & FAIR CBM) • QCD structure of hadrons: • RHIC spin program 8-10 yr. • On the horizon – spin and small-x physics: - e+p, e+A 2015 … Berkeley, May13, 2006
Exploration of Nuclear Phase Diagram Large uncertainties in model predictions. Data is important. M.A Stephanov, Prog. Theor. Phys. Suppl. 153, 139(2004); Int. J. Mod. Phys. A20, 4387(05); hep-ph/0402115 LHC RHIC+FAIR boundary between phases boundary between phases = sQGP -> wQGP = Berkeley, May13, 2006
HI experimental directions • Study phase transition at RHIC and at FAIR good overlap between RHIC and FAIR covers AGS and SPS energies Plan: energy scan at RHIC down to 4.6 -> extend scan to 2.1 (GeV) with FAIR Pioneering exploration of baryon rich plasma ! • Study of hypothesis of weakly coupled QGP at LHC 2.1 FAIR 8.1 GeV 4.6 RHIC 20. GeV Berkeley, May13, 2006
Theoretical Directions in QCD Address theoretical challenges in QCD: • Properties of strongly interacting matter • quantitatively describe and understand observed phenomena at RHIC using hard probes • transport properties of strongly interacting matter • mechanism of early thermalization in A+A • Structure of proton • nucleon’s spin structure, tomography of nucleon • Structure of nuclei at small-x • gluon saturation and non-linear dynamics in QCD Theory parallels experimental program = unique at LBNL Berkeley, May13, 2006
Issues in Nuclear Theory • Implement of the recommendations by the NSAC theory subcommittee • establish Centers of Excellence and Topical Centers in nuclear theory • establish national fellowships in nuclear theory • LBNL has submitted LOI for a topical center on the study of hard probes in high-energy heavy-ion collisions. • Other topical centers are possible e.g. exploration of Baryon Rich Matter Berkeley, May13, 2006
Nucleon Spin Structure Projected gluon polarization uncertainties at RHIC RHIC spin: - measure gluon polarization, - separate valence and sea quark polarization. Large positive gluon polarization Requires: - >~ 200 pb-1 integrated luminosity, - 200 and 500 GeV c.m.s. energy, - forward tracking upgrade at STAR. Extensive longitudinal pp-running at RHIC, Timely and well-funded detector upgrades. Large negative gluon polarization Berkeley, May13, 2006
Our interests • Support theory, topical centers • RHIC A+A/p+A program + upgrades (ToF, HFT) • RHIC p+p spin program • LHC p+p, p+A, A+A program • Baryon Rich Physics program (RHIC/FAIR) • e+p, e+A, cosmic+A low-x physics program • Outreach and education Berkeley, May13, 2006
Our expertise + leadership • Run RHIC program + upgrades AA, pA, spin • LHC-ALICE, hard probes program • Baryon Rich Physics program (RHIC & FAIR) • Theory Expertise, experience -> homework Berkeley, May13, 2006
two classes of programs: Programs with a large momentum on national scale - guaranteed place in LRP – homework would be useful, but not necessary Programs which need to be helped in preparation of physics case for LRP - homework is required e.g. support for theory topical centers Baryon Rich Physics @RHICBR/FAIR LHC/ALICE hard probes – US participation e+ppolarized … e.g. AA at RHIC RHIC spin outreach and education … No ranking ! sun will rise no matter what … sun may rise if we do our homework ? Berkeley, May13, 2006
next 40+ slides ? next: there are 40+ slides, that we can extend discussion on any of these topics …. Berkeley, May13, 2006
RHIC - sQGP ! Berkeley, May13, 2006
Collectivity, Deconfinement at RHIC - v2, spectra of light hadrons and multi-strange hadrons - scaling by the number of quarks At RHIC: mT - NQ scaling Partonic Collectivity Deconfinement PHENIX: PRL91, 182301(03) STAR: PRL92, 052302(04), 95, 122301(05) nucl-ex/0405022, QM05 S. Voloshin, NPA715, 379(03) Models: Greco et al, PRC68, 034904(03) Chen, Ko, nucl-th/0602025 Nonaka et al. PLB583, 73(04) X. Dong, et al., Phys. Lett. B597, 328(04). …. i ii Berkeley, May13, 2006
Thermalization at RHIC - non-photonic electron v2 (non-photonic electrons arise primarily from c and b) Charm flows - a hint for partonic thermalization at RHIC! Future measurements with direct reconstructed D0 should distinguish between flow scenarios. Berkeley, May13, 2006
Not what we expected ! charm not only flows but also is suppressed ! Comparison with models: Theory: RAA>0.4 Data: RAA<0.3 ???? : • Is our understanding of partonic energy loss correct? • How strong are the in-medium interactions? • How dense is the medium? • Is our understanding of c and b production correct? Needs direct measurement of charm: HFT Needs more theoretical work!!! Berkeley, May13, 2006
Direct topological identification of charm-hadrons in STAR HFT - to complete experimental program and supply theory with precision data (e.g. separation between c and b production) 1) de-composition of c and b 2) D0, Ds, D+, c and their anti-particles can be reconstructed with the combination of the HFT+SSD*+TOF+TPC. 3) Decent reconstruction efficiencies at low pT region - important for flow analysis. Berkeley, May13, 2006
HFT because it • RNC leading force behind HFT (operational in 2009) • should allow to resolve most important issues and conclude our research program at RHIC degree of thermalisation partonic collectivity, deconfinment mechanism of quenching …. in the next 10 years - precision data on sQGP heavy flavor collectivity light flavor thermalization Berkeley, May13, 2006
How does the medium respond ? 4.0 < pT(trig) < 6.0 GeV/c ? 2.0<pT(assoc)<pT(trig) GeV/c 0.15<pT(assoc)<4.0 GeV/c • In central Au+Au collisions: • Strong suppression of inclusive hadron production • Disappearance of the away-side jet • Jet quenching in the dense medium • - Hot and dense matter created • but … limitations : leading hadrons preferentially arise from the surface limited sensitivity to the region of highest energy density need more penetrating probes need to trigger on jets (clean probe) ! • Reappearance of away side peak • away-side particles increase in number and soften in pT – energy deposited into medium Berkeley, May13, 2006
baryon rich physics low energy run at RHIC and at FAIR Berkeley, May13, 2006
RHIC Injection energy: 9.8 => 2.3 GeV The center of mass energy: 200 - 4.6 GeV Low energy scan program: 20 - 4.6 GeV
Observables • spectra, v2, and HBT of , K, p, , , , , , D, J/ • vector mesons: , a1, , … • fluctuations: N(h±) , N(K)/N(), pT, … • beam energy: 5-, 10-, and 20-GeV • p+p and A+A plus sufficient number of events • Step I: Disappearance of partonic activities • Step II: Fluctuation and vector meson production
International Facility for Antiproton and Ion Research (FAIR) 238U up to 35 GeV/u CBM Experiment Observables: Penetrating probes: r, w, j, J/y → e+e- (μ+μ-) Strangeness: K, L, S, X, W, Open charm: Do, D±, Ds, Lc, global features: collective flow, fluctuations, ..., exotica Berkeley, May13, 2006 Silicon Tracking System
LHC Berkeley, May13, 2006
Large Hadron Collider 2007/8 27 km around Systems: pp (14 TeV), pA (8 TeV), AA (5.5 TeV) Berkeley, May13, 2006
New at LHC: dominance of hard processes (h++h-)/2 p0 √s = 5500 GeV LO p+p y=0 200 GeV 17 GeV • Bulk properties dominated by hard processes; LHC RHIC SPS • fireball hoter and denser • longer lifetime • initial hard processes contribute significantly to the total AA cross-section(σhard/σtot = 98%) • Very hard probes are abundantly produced. Qualitatively new features • High energy jets ~fully reconstructable in heavy ion collisions unbiased jet population (contrast to leading particle analyses) • Large kinematic reach:study of evolution of energy loss • Heavy quarks over broad range: unique energy dependence • similar measurements as RHIC provide crucial cross checks and calibration Berkeley, May13, 2006
ALICE ( ~ STAR+PHENIX with upgrades) Jet analysis requires excellent tracking and PID ALICE ! THEORY Berkeley, May13, 2006
US: EMCal for ALICE |h|<0.7, Df=110o ~13K towers (DhxDf~0.014x0.014) EMCal will allow for: Trigger on jets, photons, electrons Jets and dijets beyond ET~150 GeV Huge statistics for g and p0 Electron/hadron discrimination Berkeley, May13, 2006
SPIN –MAY 12 Berkeley, May13, 2006
? Nucleon Spin Structure Frisch and Stern: The proton has substructure 1933 ~1970 Electron-proton deep-inelastic scattering: Quarks are spin-1/2 time ~1985 Polarized deep-inelastic scattering: Quark spins carry only a small fraction of the nucleon spin. ~2002 RHIC: first polarized proton-proton collider Berkeley, May13, 2006 2
representative polarized lepton-proton data Q2 ~ 10 GeV2 Q2 ~ 5 GeV2 Nucleon Spin Structure - Present Knowledge A decade of polarized lepton-nucleon scattering: - The sum ofquark spins amounts to only a small fraction of the nucleon spin (~25%), The unknowns: - gluon polarization, - the valence and sea quark spin structure, - orbital momenta. Berkeley, May13, 2006
Nucleon Spin Structure - Gluon Polarization at RHIC Projected gluon polarization uncertainties at RHIC RHIC spin: - measure gluon polarization, Needs: - >~ 200 pb-1 integrated luminosity, - 200 and 500 GeV c.m.s. energy, Extensive longitudinal pp-running at RHIC Berkeley, May13, 2006
Nucleon Spin Structure - Valence and Sea Quarks at RHIC RHIC spin: - separate valence and sea quark polarization, Needs: - forward tracking upgrade at STAR. - >~ 200 pb-1 integrated luminosity, - 500 GeV c.m.s. energy, Timely and well-funded detector upgrade paths, Extensive longitudinal pp-running at RHIC Berkeley, May13, 2006
Nucleon Spin Structure - beyond the RHIC baseline Second generation gluon-polarization measurement, Strange-quark spin structure, Transverse nucleon spin structure, Orbital momenta and spatial structure, Electroweak structure functions, Precision tests of QCD. Roles for RHIC, eRHIC, JLAB, FAIR, and elastic neutrino scattering Berkeley, May13, 2006
spin Berkeley, May13, 2006
Nucleon Spin Structure - Present Knowledge representative polarized lepton-proton data A decade of fixed-target polarized lepton-nucleon deep-inelastic scattering experiments have mea-sured the inclusive spin structure function g1 of the proton and neutron, and mapped its depen-dences on x, the momentum fraction of the struck quark, and Q2, the virtuality of the photon probe: - A tenet of QCD, the Bjorken sum rule, was tested and confirmed to within ~7% uncertainty, - Quark spins carry only a small fraction of the nucleon spin, - Voids remain in the knowledge at small-x, of the valence and sea quark spin structure, of gluon spins, and of orbital momenta. Berkeley, May13, 2006
Double-Spin Asymmetry in Inclusive Jet production Preliminary, ~1 pb-1 large positive gluon polarization large negative gluon polarization no gluon polarization gluon polarization from best fit to DIS data Nucleon Spin Structure - Gluon Spin at RHIC RHIC is the first polarized proton collider, enabling experiments to study spin effects in which gluons contribute at leading order, and to reach large center-of-mass energies. First results are starting to appear, however, the physics program is still in its infancy. Specifically, extensive data collection periods over the upcoming 5+ years should eliminate the evident statistics starvation, and enable: - correlation measurements to resolve parton kinematics (~10+ pb-1), - process-selective measurements; heavy-quark production to enhance gluon-gluon scattering, and prompt-photon production to select quark-gluon scattering (~50+ pb-1). Berkeley, May13, 2006 Note: limited benefits from beam-cooling at RHIC, large benefits from detector upgrades (e.g. DAQ).
Nucleon Spin Structure - Valence and Sea Quarks at RHIC Polarized proton collisions at 500 GeV center-of-mass energy allow experiments to study parity-violating spin effects in weak-boson production production, giving access to valence and sea quark polarization in the polarized nucleon. Weak-bosons act as polarimeters for valence and sea quarks in the polarized nucleon, - forward single beam-spin asymmetries are sensitive to quark-polarization; backward single beam-spin asymmetries to anti-quark polarization, - W+/W- charge separation at large pT and pseudo-rapidity separates the light quark flavors, These measurements require extensive (100+ pb-1) data collection periods and, at STAR, new tracking capability at large pseudo-rapidity. Berkeley, May13, 2006
Precision tests of QCD; Bjorken Sum Rule, Running of Gluon polarization, Gluon polarization at small x, x < 10-2, Strange (anti-)quark polarization, Orbital angular momenta, Parity Violating Spin Structure Functions, ... High-energy polarized electron-ion collider, High-energy polarized electron-ion collider, Elastic-neutrino scattering niche, polarized electron-ion collider, JLAB 12 GeV upgrade, High luminosity polarized electron-ion collider, High energy electron-ion collider ... Nucleon Spin Structure - Longer Term Future Berkeley, May13, 2006
low-x physics with cosmic rays Berkeley, May13, 2006
108 eV 1021 eV Probing gluon saturationusing Cosmic Rays • Cosmic Rays have been observed with energies up to 3*1020 eV • Some evidence they are mostly protons • pA collisions up to Ecm = 800 TeV/nucleon • 80* LHC energy for pA • 2 ways to study low-x gluons • Measure snN at high energies • Absorption in the earth • Study charm/bottom production in high energy pA collisions • IceCube can do both studies Berkeley, May13, 2006
Measuring snN by neutrino absorption in the earth • Atmospheric and extraterrestrial n have known angular distributions • The earth becomes opaque to neutrinos with energies > ~ 200 TeV • Measure cross section by studying n flux as f(zenith angle, energy) • Absorption ~ snN which is proportional to weak charge (quarks) • Maximum energy ~ 10-100 PeV x value depend on n energy • En = 1016 eV --> x ~ 10-3 • En – 1017 eV --> x ~ 10-4 Absorber thickness Depends on zenith angle quark distribution at x= 10-3 – 10-4 Berkeley, May13, 2006
Cosmic-ray air showers to study c and b production Cosmic Ray • Mostly p(?)-nitrogen collisions • Soft component – g,e • Detected and by air shower arrays (+stopped) • Muons from p,K decay • Soft energy spectrum since high energy p,K interact instead of decaying • GeV to TeV energies • Low pT; produced near the ‘core’ of the shower • Muons from charm/bottom decay • Dominant source for Em > 100 TeV • Larger pT than m from p,K decay • Measure muon energy with dE/dx • For Em > 1 TeV Em ~ dE/dx • Measure muon pT via distance from core N2 e,g m From c,b m from p,K Berkeley, May13, 2006
Charm and Bottom Production Cosmic Ray N2 30 km e,g m From c,b m from p,K • Separate muons from p,K decay and from c,b decay via cuts on Em, pT • Transform Em, pT --> rapidity, pT • Follow RHIC single lepton analyses to find charm, bottom • Measure charm and bottom production at high pT • study low-x parton densities in nitrogen • x range from 10-6 (Q2 > 100 GeV2) CONCLUSIONS: Cosmic-rays include very high energy particles which can be exploited to study low-x parton distributions IceCube can study small-x distributions with two techniques Berkeley, May13, 2006