Od odkrycia do poznania wlasnosci plazmy kwarkowo-gluonowej

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1 Od odkrycia do poznania wlasnosci plazmy kwarkowo-gluonowej Plan : Plazma? CERN SPS, RHIC, LHC,... Wykres fazowy silnie oddzialywujacej materii jadrowej - #1 fizyki jadrowej Badanie struktury - eksperyment przejmuje prowadzenie! RHIC, LHC, / LBNL, Berkeley

2 CERN in 2000! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

3 RHIC discovery! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

4 DETOUR (1): Quantum Chromodynamics 1) Quantum Chromodynamics (QCD) is the established theory of strongly interacting matter. 2) Gluons hold quarks together to form hadrons: meson baryon 3) Gluons and quarks, or partons, typically exist in a color singlet state: confinement. Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

5 DETOUR (2): Quark Gluon Plasma - The confinement: Quarks are the basic building blocks of matter. No free quarks are seen, confined within hadron: v 0 ~ 1 fm 3, 0 ~ 0.16 fm -3, 0 ~ 0.15 GeV/fm 3 - Heavy ion collisions: Large, hot, and dense system v ~ 1000 fm 3 = 1000 v 0 >> 3 fm -3 ~ 20 0 QGP(?) >> 3 GeV/fm 3 ~ 20 0 Quarks and gluons are freely moving in a large volume New form of matter with partonic degrees of freedom - Connection with other fields cosmology, origin of the universe, evolution of the universe quantum statistics with partons Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

6 DETOUR (3): Confinement Potential V(r,T) T < T conf constant potential The potential between quarks is a function of distance. It also depends on the temperature. 1) At low temperature, the potential increases linearly with the distance between quarks quarks are confined; 2) At high temperature, the confinement potential is melted quarks are free. T > T conf r Note: It is not clear at all if there is a critical temperature in high energy collisions Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

7 DETOUR (4): Lattice QCD Predictions Energy density Heavy quark potential Temperature Left: Large increase in energy density at T C ~ 170 MeV. Not reach the non-interacting S.B. limit. Right: Heavy quark potentials are melted at high temperature. F. Karsch et al. Nucl. Phys. B524, 123(02). Z. Fodor et al, JHEP 0203:014(02). C.R. Allton et al, Nucl. Rev. D66, (02). F. Karsch, Nucl. Phys. A698, 199c(02). Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

8 cross-over Phases of Water 1st order phase transition CP Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

9 QCD Phase Diagram WATER: the phase diagram of water is well established (non-relativistic particles) QCD: The phase diagram of strongly interacting matter is under study (relativistic particles) Cross-over CP 1 st order phase transition Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

10 Phases of strongly interacting matter (?) QGP HG SPS, RHIC, LHC: high temperature, low baryon density AGS, GSI: moderate temperature, high baryon density Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

11 From Fermi s notes on thermodynamics:! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

12 ! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec 2009

13 hep-lat/ v1 Theory Lattice - green points! m B <500 Given the very significant theoretical difficulties, data may lead the study of QCD phase diagram Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

14 How do we do it? High-energy nuclear collisions RHIC Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

15 High-energy Nuclear Collisions t S. Bass t=0 Initial CYM & LGT 2 conditions Initial high Q PCM & clust. hadronization Partonic matter interactions QGP - The hot-qcd NFD Hadronization and Freeze-out NFD & hadronic TM (1) Chemical freeze-out (2) Thermal string freeze-out & hadronic TM Konwersatorium, Politechnika Warszawska, PCM & hadronic TM Wydzial Fizyki, 12 marzec

16 Relativistic Heavy Ion Collider (RHIC) Brookhaven National Laboratory (BNL), Upton, NY PHENIX PHOBOS STAR RHIC BRAHMS v = c = 186,000 miles/sec Au + Au at 200 GeV AGS TANDEMS Animation M. Lisa Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

17 Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

18 PHENIX RHIC experiments STAR STAR Focus: global observables Large volume TPC (2p) +EM calorimetry (coarse) Focus: rare probes, e ±, m Partial coverage High-granularity calorimetry and tracking Forward muon detectors Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

19 STAR Collaboration Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

20 Au + Au Collisions at 130 GeV Peripheral Event Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec 2009 STAR 20 (real-time Level 3)

21 Au + Au Collisions at 130 GeV Mid-Central Event Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec 2009 STAR 21 (real-time Level 3)

22 Au + Au Collisions at RHIC Central Event Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec 2009 STAR 22 (real-time Level 3)

23 (1) What did we learned? Probing hot and dense matter (QGP?) with hard probes Lawrence Berkeley National Laboratory Konwersatorium na Wydziale Fizyki Politechniki Warszwskiej, 24 maja 2007 Elliptic Flow Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

24 Azimuthal Anisotropy - Elliptic Flow Origin: spatial anisotropy of the system when created and rescattering of evolving system spatial anisotropy momentum anisotropy x space momentum Reaction-plane: x-z plane Almond shape overlap region in coordinate space y2 x 2 y 2 x 2 v 2 cos2 atan Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec p p y x

25 Elliptic Flow Large Elliptic Flow: A Signal of Strong Space-Momentum Correlations Space Momentum y2 x 2 y 2 x 2 v 2 cos2 atan p p y x 25 Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

26 Perfect fluid? Detailed analysis of v 2 for different mass shows good agreement with ideal (zero viscosity, l=0) hydrodynamics perfect fluid? Separation between baryon and meson band Note: s flow! (also W s) as light h flow developed in pre-hadronic stage DECONFINEMENT!!! (a lot of scatterings thermalization?) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

27 Partonic degrees of freedom Scaling flow parameters by quark content n q (baryons=3, mesons=2) resolves meson-baryon separation of final state hadrons liquid of partons! (1) v 2 developed at pre-hadronic state indicates a lot of interactions between q and g, some thermalization? (2) deconfinement (3) Novel hadronization process at RHIC Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

28 A short summary (I) : m T -N q scaling Partonic collectivity Deconfinement Hot and dense matter with partonic collectivity has been formed at RHIC Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

29 (2) What did we learned? Jets Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

30 Jets in heavy-ion collisions Partons lose energy due to induced gluon radiation (Bjorken, Gyulassy, X.N. Wang, ) Energy loss is measure of gluon density p+p Nuclear Medium q hadrons q hadrons leading particle suppressed q q q q hadrons hadrons leading particle leading particle suppressed Quenched dijets Probe energy loss via leading hadrons (2) and di-hadron correlations (2) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

31 Not easy! p+p dijet How to find it here? Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

32 How to measure? 1. R AA : Compare A+A and p+p collisions Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

33 R AA 2 AA d N / dpt d ( pt ) 2 NN T d / dp d AA Jets are quenched, part I - R AA T Photons (colorneutral) Jets (colorcharged) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

34 Jets are quenched, part II - correlations Hard recoil hadrons All recoil hadrons cos( ) STAR, Phys Rev Lett 91, STAR, Phys Rev Lett 95, Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

35 A short summary (II) : Photons are not suppressed good! They do not interact with medium Hadrons are not suppressed in peripheral collisons good! Medium not dense Hadrons are suppressed in central collisions huge: factor 5! Azimuthal correlation shows ~ complete absence of : away-side jet partner in hard scatter is absorbed in the dense medium High pt suppression - Matter is opaque! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

36 Top discoveries at RHIC Strong elliptic flow collective flow of created matter partonic collectivity deconfinement Jet quenching Energy loss of high pt partons in hot and dense medium Medium response ridge? Production mechanism at medium pt via recombination/coalescence (not via fragmentation) Strongly coupled QGP = sqgp not wqgp surprise, surprise!!! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

37 First point 100 years ago! One Century of Nuclear Physics In 1911, Rutherford discovered the nucleus, making him the first nuclear physicist 100 years later, RHIC will scan for the next landmark on the nuclear matter phase diagram: the critical point 37 Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

38 Summarizing the situation : Now: sqgp produced in A+A at RHIC at top energies (hot and dense matter with partonic dof) Problem: we still don t know much about sqgp! Future: (wqgp ) properties of sqgp RHIC, LHC,? boundary between hadronic and partonic phases (where is a phase transition?) RICH, Fear, CP Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

39 Beam Energy Scan at RHIC: RHIC: Ideally Suited 5-50 GeV 39 Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

40 PID matters: Phase Transitions Rutherford's discovery of the nucleus in 1911 relied on state-of-the art technology developed by Hans Geiger to count alpha particles. The state-of-the-art technology at the heart of STAR's Time-of-Flight upgrade significantly increases the possibility that STAR will locate that other landmark on the nuclear matter map: the critical point. 40 Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

41 Particle Identification at STAR TPC ToF TPC STAR TPC K p d π e, μ STAR ToF Log 10 (p) STAR HFT STAR EMC Neutral particles Strange Jets Heavy Quark hyperons Hadrons Multiple-fold correlations among the identified particles! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

42 Run 10, fall 2009 energies likely to be proposed by STAR s NN (GeV) Rate (Evts/sec) 10 hr days for 1 M Evts These energies are all logarithmically equally spaced (constant multiplicative factor of ~1.5) between s NN = 5.0 and 62.4 GeV, except for 39 GeV, which is shifted slightly from 41 GeV to match existing pp data. Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

43 STAR run plan for BES physics objectives Search for turn-off of major sqgp signatures already established at top RHIC energies (our least speculative objective). Search for phase transition signatures of the type that appear and then disappear as the beam energy is scanned. Search for evidence of critical point. Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

44 STAR experience with Low Energy RHIC running 2001: 19.6 GeV Au+Au 2004: 22.4 GeV Cu+Cu 2007: 9 GeV Au+Au 2008: 9 (5) GeV Au+Au! D. Cebra QM2008 Preliminary Preliminary Sufficient data to extract ratios, flow velocity, HBT radii, v2 Data fit into systematics E802 PRL81, 2650 (1998) E866 PLB476, 1 (2000) E917 PLB490, 53 (2000) NA44 PLB471, 6 (1999) WA98 PRC67, (2003) NA49 PRC66, (2002) NA49 EPJC33, S621 (2004) NA49 arxiv: v2 PHENIX PRC69, (2004) PHENIX PRL88, (2002) STAR PRL92, (2003) STAR PLB595, 143 (2004) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

45 2008: low energy run with 9.2 GeV Au+Au Injecting and colliding Au+Au s NN = 9.2 GeV, a few hours -> 4K good events! Short s NN = 5 GeV allowed study of beam optics Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

46 Vertex Y Au+Au and Au+Al collisions! Investigated primary vertex location: They are real collisions. Au+Au collisions Au+Beampipe collisions R. Reed Vertex X Au+Al Au+Be Au+Al Vertex Z (cm) Can see the change in beampipe material and thickness Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

47 9.2 GeV Au+Au, March 2008 preliminary analysis Lambda invariant mass (SQM 2008) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

48 The unique RHIC energy scan program will map the QCD diagram in s NN =5-50 GeV, (corresponding to m B ~ MeV) STAR is tested and ready (DAQ, trigger, all) First run fall 2009 Informal discussion between STAR and PHENIX Late-breaking news: likely $4.5M Economic Stimulus funding for RHIC electron cooling, with an order of magnitude intensity increase down to s NN ~ 5 GeV, coming online in (a shovel ready project). Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

49 Hard physics, RHIC II,LHC What next (rather parallel) besides BES? vertical direction: T (m B ~0) QCD Phase Transition, CP, BES/RHIC, FAIR/GSI, Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

50 LHC p+p 14 TeV (2009?) Pb+Pb 5.5 TeV (2010+) CMS ALICE ATLAS ALICE is the dedicated Heavy-Ion experiment (high-density tracking and PID) CMS and ATLAS are likely to participate in HI runs as well

51 LHC and ALICE! Better environment for high-pt physics than RHIC High-pt processes increase faster than soft background Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

52 ALICE installation (already historical pictures!) Installation of TPC Installation of Silicon Inner Tracker Installation of Beam Pipe Inner tracker Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

53 Hard process rates at the LHC Annual yields for Pb+Pb at LHC Jet rates and kinematic reach at LHC are huge compared to RHIC E T jet >100 GeV ~ 10 6 /year High statistics measurements over large kinematic range for precision test of theory Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

54 Energy (GeV) Jet reconstruction at LHC 100 GeV jet in central Pb+Pb Jet yields at high energies (>50 GeV) are large enough for full jet reconstruction Full jet reco removes fragmentation bias Study jet quenching (modified fragmentation) in more detail Jets accessible over large energy range ( GeV from full jet reco) Validate jet quenching mechanism E LHC 40 GeV need E T,Jet ~200 GeV for E>> E And more: Heavy quark jets -jet correlations (calibrate kinematics) Suprises? Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

55 US contribution to ALICE ALICE EMCal Lead-scintillator sampling calorimeter <0.7, =110 o Shashlik geometry, APD photosensor ~13k towers ( x ~0.014x0.014) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

56 Summary The initial expectation at RHIC of an ideal gas plasma of noninteracting quarks and gluons is a distant memory. Instead, something much more interesting has been found: The most perfect fluid known, with equilibrium and dynamical properties that are calculable from basic theory, perhaps including string theory. In the next five years: BES program at RHIC RHIC and detector upgrades Run the LHC HI program (wqgp?) Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

57 THANKS! Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

58 ETRA SLIDES Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

59 log 10 (de/dx) Particle Identification in STAR TPC+TOF (completed in 2010)+EMC+Topology TOF alone: (p,k) up to 1.6 GeV/c, p up to 3 GeV/c log 10 (p) TOF+TPC(dE/dx, topology) up to 12 GeV (NIMA 558 (419) 2006) Good quality PID over a broad range: ~ GeV/c Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

60 BES at RHIC - access to large range of m B and T produces systems with lower freezout temperatures and higher baryon densities -explore a broad region of the QCD phase diagram -look for the evidence of ordered transition -study the evolution with beam energy of the unusual medium properties found at RHIC -do any of the partonic properties change or turn off? -new surprises in unexplored region advantage of collider geometry! At fixed target geometry: detector acceptance changes with energy track density at mid-y increases fast with energy -> technical difficulties in tracking Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

61 What should be measured during BES? Mainly related to bulk properties yields and particle ratios T vs m B, particle spactra (p t, rapidity, ), strangeness production (K/p, multistrange, ), fluctuations and correlations of many varietes (K/p,<p t >, 2, ) flow (v1,v2,v4, ) with charged and identified particles, signals of parity violation, lumpy ( clumpy?) final state prospect of data will encourage theorists to be more specific Search for : - disappearance of partonic activities - fluctuations, correlations turn on and off signature of deconfinement Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec

62 Acceptance Colliders are a great choice for E-scan π NA49 K π STAR K Occupancy for collider detectors is much less dependent on beam energy Acceptance for collider detectors is totally independent of beam energy Less problems with track merging, charge sharing hits etc.. Better control of systematics Konwersatorium, Politechnika Warszawska, Wydzial Fizyki, 12 marzec