2. June 5, 2002REU Seminar, University of Rochester1 Searching for a new form of matter on Long Island Steve Manly, University of Rochester 12 June, 2000: 1 st Collisions @  s = 56 AGeV 24 June, 2000: 1 st Collisions @  s = 130 AGeV July 2001: 1 st Collisions @  s = 200 AGeV

3. June 5, 2002REU Seminar, University of Rochester2 Places to learn more: Particle and nuclear physics links http://pdg.lbl.gov http://particleadventure.org http://www.aps.org/dpf/education.html http://www.slac.stanford.edu/gen/edu/aboutslac.html http://www.bnl.gov/bnlweb/sciindex.html http://www.rhic.bnl.gov/ http://welcome.cern.ch/welcome/gateway.html http://www.fnal.gov/ http://www.er.doe.gov/production/henp/np/index.html

4. June 5, 2002REU Seminar, University of Rochester3 The starting point What is matter?

5. June 5, 2002REU Seminar, University of Rochester4 Stuff Lump A little bit A molecule An atom

6. June 5, 2002REU Seminar, University of Rochester5

7. June 5, 2002REU Seminar, University of Rochester6 Before

8. June 5, 2002REU Seminar, University of Rochester7 How do they interact? After

9. June 5, 2002REU Seminar, University of Rochester8 What forces exist in nature? What is a force? How do forces change with energy or temperature? How has the universe evolved?

10. June 5, 2002REU Seminar, University of Rochester9 The fundamental nature of forces: virtual particles  E  t  h Heisenberg E = mc 2 Einstein e-e-

11. June 5, 2002REU Seminar, University of Rochester10

12. June 5, 2002REU Seminar, University of Rochester11 quarks leptons Gauge bosons u c t d s b e   W, Z, , g, G g Hadrons Baryons qqq qq mesons p = uud n = udd K = us or us  = ud or ud Strong interaction nuclei e atoms Electromagnetic interaction

13. June 5, 2002REU Seminar, University of Rochester12 Quantum Chromodynamics - QCD Gauge field carries the charge q q distance energy density, temperature relative strength asymptotic freedom qq qq confinement q q

14. June 5, 2002REU Seminar, University of Rochester13 Why do we believe QCD is a good description of the strong interaction? Deep inelastic scattering: There are quarks.

15. June 5, 2002REU Seminar, University of Rochester14 Why do we believe QCD is a good description of the strong interaction? No direct observation of quarks: confinement

16. June 5, 2002REU Seminar, University of Rochester15 Why do we believe QCD is a good description of the strong interaction?

17. June 5, 2002REU Seminar, University of Rochester16 Why do we believe QCD is a good description of the strong interaction? Event shapes

18. June 5, 2002REU Seminar, University of Rochester17 Why do we believe QCD is a good description of the strong interaction? Measure the coupling

19. June 5, 2002REU Seminar, University of Rochester18

20. June 5, 2002REU Seminar, University of Rochester19

21. June 5, 2002REU Seminar, University of Rochester20 Relativistic heavy ions Two concentric superconducting magnet rings, 3.8 km circum. A-A (up to Au), p-A, p-p collisions, eventual polarized protons Funded by U.S. Dept. of Energy $616 million Construction began Jan. 1991, first collisions June 2000 Annual operating cost $100 million Reached 10% of design luminosity in 2000 (1st physics run)!! AGS: fixed target, 4.8 GeV/nucleon pair SPS: fixed target, 17 GeV/nucleon pair RHIC: collider, 200 GeV/nucleon pair LHC: collider, 5.4 TeV/nucleon pair

22. June 5, 2002REU Seminar, University of Rochester21

23. June 5, 2002REU Seminar, University of Rochester22 The goals  Establish/characterize the expected QCD deconfinement phase transition quarks+gluons hadrons  Establish/characterize changes in the QCD vacuum at high energies: chiral symmetry restoration and/or disoriented chiral condensates  Polarized proton physics

24. June 5, 2002REU Seminar, University of Rochester23 Coin of the realm Centrality Energy density, number of participants, multiplicity, zero degree energy (nuclear fragments) Temperature  Entropy, energy density  Chemical potential  species yields Thermal equilibration peripheral central Vary conditions by varying species, energy and centrality

25. June 5, 2002REU Seminar, University of Rochester24 Signatures/observables Energy density or number of participants Measured value Strange particle enhancement and particle yields Temperature J/  and  ’ production/suppression Vector meson masses and widths identical particle quantum correlations DCC - isospin fluctuations Flow of particles/energy (azimuthal asymmetries) jet quenching Each variable has different experimental systematics and model dependences on extraction and interpretation MUST CORRELATE VARIABLES

26. June 5, 2002REU Seminar, University of Rochester25

27. June 5, 2002REU Seminar, University of Rochester26 Event in STAR

28. June 5, 2002REU Seminar, University of Rochester27 Isometric of PHENIX Detector

29. June 5, 2002REU Seminar, University of Rochester28 Perspective View of Spectrometer From F.Videbœk

30. June 5, 2002REU Seminar, University of Rochester29 The PHOBOS Detector (2001) Ring Counters Time of Flight Spectrometer 4  Multiplicity Array - Octagon, Vertex & Ring Counters Mid-rapidity Spectrometer TOF wall for high-momentum PID Triggering - Scintillator Paddles Counters - Zero Degree Calorimeter (ZDC) Vertex Octagon ZDC z y x   Paddle Trigger Counter Cerenkov 137000 silicon pad readout channels 1m

31. June 5, 2002REU Seminar, University of Rochester30 Central Part of the Detector (not to scale) 0.5m

32. June 5, 2002REU Seminar, University of Rochester31 Silicon detector scheme +HV p+ Implant n+ Polysilicon Drain Resistor Dielectric 1 bias bussignal lines Dielectric 2vias metal 1 metal 2 Primary detector technology Silicon strips and pads 300 microns

33. June 5, 2002REU Seminar, University of Rochester32

34. June 5, 2002REU Seminar, University of Rochester33 ARGONNE NATIONAL LABORATORY Birger Back, Alan Wuosmaa BROOKHAVEN NATIONAL LABORATORY Mark Baker, Donald Barton, Alan Carroll, Joel Corbo, Nigel George, Stephen Gushue, Dale Hicks, Burt Holzman, Robert Pak, Marc Rafelski, Louis Remsberg, Peter Steinberg, Andrei Sukhanov INSTITUTE OF NUCLEAR PHYSICS, KRAKOW Andrzej Budzanowski, Roman Holynski, Jerzy Michalowski, Andrzej Olszewski, Pawel Sawicki, Marek Stodulski, Adam Trzupek, Barbara Wosiek, Krzysztof Wozniak MASSACHUSETTS INSTITUTE OF TECHNOLOGY Wit Busza, Patrick Decowski, Kristjan Gulbrandsen, Conor Henderson, Jay Kane, Judith Katzy, Piotr Kulinich, Johannes Muelmenstaedt, Heinz Pernegger, Michel Rbeiz, Corey Reed, Christof Roland, Gunther Roland, Leslie Rosenberg, Pradeep Sarin, Stephen Steadman, George Stephans, Gerrit van Nieuwenhuizen, Carla Vale, Robin Verdier, Bernard Wadsworth, Bolek Wyslouch NATIONAL CENTRAL UNIVERSITY, TAIWAN Chia Ming Kuo, Willis Lin, JawLuen Tang UNIVERSITY OF ROCHESTER Joshua Hamblen, Erik Johnson, Nazim Khan, Steven Manly, Inkyu Park, Wojtek Skulski, Ray Teng, Frank Wolfs UNIVERSITY OF ILLINOIS AT CHICAGO Russell Betts, Edmundo Garcia, Clive Halliwell, David Hofman, Richard Hollis, Aneta Iordanova, Wojtek Kucewicz, Don McLeod, Rachid Nouicer, Michael Reuter, Joe, Sagerer UNIVERSITY OF MARYLAND Abigail Bickley, Richard Bindel, Alice Mignerey The Phobos Collaboration

35. June 5, 2002REU Seminar, University of Rochester34 6% cut on paddle signal  gives ~6% events with highest N part Measuring Centrality in PHOBOS DATA Simulation N part Paddle Signal N part Au x z

36. June 5, 2002REU Seminar, University of Rochester35 Phobos and global event-by-event variables   RingsN Octagon RingsP Small acceptance tracking capability Large acceptance multiplicity detector

37. June 5, 2002REU Seminar, University of Rochester36 Phobos and global event-by-event variables 1m 2m 5m 01234512345  coverage for vtx at z=0 Large acceptance multiplicity detector

38. June 5, 2002REU Seminar, University of Rochester37 Phobos and global event-by-event variables 1m 2m 5m 0+3-3 +5.5-5.5   Study patterns/asymmetries of hits and energy deposition

39. June 5, 2002REU Seminar, University of Rochester38 -1.1 m 1.1 m 2.3 m -2.3 m 5.0 m - 5.0m |  | < 5.5 ( , 0  (  Interaction Point Octagon, vertex and ring detectors Ring counter

40. June 5, 2002REU Seminar, University of Rochester39 -1.1 m 1.1 m 2.3 m -2.3 m 5.0 m - 5.0m |  | < 5.5 ( , 0  (  Octagon, vertex and ring detectors octagon vertex detector

41. June 5, 2002REU Seminar, University of Rochester40 -1.1 m 1.1 m 2.3 m -2.3 m 5.0 m - 5.0m |  | < 5.5 ( , 0  (  Octagon, vertex and ring detectors vertex detector

42. June 5, 2002REU Seminar, University of Rochester41 b (reaction plane) Elliptic flow dN/d(  R ) = N 0 (1 + 2V 1 cos (  R ) + 2V 2 cos (2(  R ) +... ) Determine to what extent is the initial state spatial/momentum anisotropy preserved in the final state. Sensitive to the initial equation of state and the degree of thermalization. Affects other variables, such as HBT and spectra.

43. June 5, 2002REU Seminar, University of Rochester42 Reaction Plane

44. June 5, 2002REU Seminar, University of Rochester43 Elliptic Flow -2.0 <  < -0.1 RingPRingN SubE (a)SubE (b) nana nbnb 0.1 <  < 2.0 Subevent technique: correlate reaction plane in one part of detector to  asymmetry in hit pattern in other part of detector Correct for imperfect reaction plane resolution (formalism given in A. M. Poskanzer,S. A. Voloshin Phys. Rev. C 58, 1671)

45. June 5, 2002REU Seminar, University of Rochester44 Determining the collision point High Resolution extrapolate spectrometer tracks Low Resolution octagon hit density peaks at vertex z position Other techniques (vertex detector hits, timing) not used in flow analysis

46. June 5, 2002REU Seminar, University of Rochester45 Event Selection Rings PRings N Octagon  z Spec holes Vtx holes

47. June 5, 2002REU Seminar, University of Rochester46 Event Selection Spec vertex available Rings PRings N Octagon  z Acceptance/symmetry issues where spec vtx efficiency is highest

48. June 5, 2002REU Seminar, University of Rochester47 Event Selection Rings PRings N Octagon  z -30 cm-38 cm Symoct analysis: Lower statistics symmetric detector

49. June 5, 2002REU Seminar, University of Rochester48 Event Selection Rings PRings N Octagon  z +10 cm-10 cm Mid-z analysis: higher statistics must deal with symmetry and acceptance issues coming soon

50. June 5, 2002REU Seminar, University of Rochester49 In all calculations, hits are weighted by w i = (w i a )(OCC( ,  )) Reaction plane determined in subevent ‘a’ Resolution determined from two subevents in a given event Average done over all events in a given centrality bin

51. June 5, 2002REU Seminar, University of Rochester50 Phase space weighting --- w i a For each annulus in eta, weight hits by the normalized, inverse integrated hit density

52. June 5, 2002REU Seminar, University of Rochester51 Reaction plane angle (radians) Events/bin Flatness of reaction plane (130 GeV data, symoct analysis)

53. June 5, 2002REU Seminar, University of Rochester52 Nasty little details - signal suppression hit saturation/occupancy Sensitivity to flow reduced as occupancy grows Can parametrize signal reduction as function of occupancy measure occupancy from energy or number of occupied and unoccupied pads assuming Poisson statistics

54. June 5, 2002REU Seminar, University of Rochester53 Where Find tracks per hit pad [OCC( ,  )] in segments of the detector Cannot integrate over  as done for dN/d  analysis

55. June 5, 2002REU Seminar, University of Rochester54 Nasty little details - signal suppression Non-flow background  z flow signal

56. June 5, 2002REU Seminar, University of Rochester55 Nasty little details - signal suppression Non-flow background  z

57. June 5, 2002REU Seminar, University of Rochester56 Nasty little details - signal suppression Non-flow background  z flow signal + non-flow background Dilutes the flow signal Estimate from MC and correct Remove Background Or both

58. June 5, 2002REU Seminar, University of Rochester57 Background suppression Works well in Octagon  dE (keV) cosh  Background! Techniques do not work in rings because angle of incidence is ~90  Beampipe Detector Demand energy deposition be consistent with angle For 1<|  |<2, demand no isolated hits

59. June 5, 2002REU Seminar, University of Rochester58 Nasty little details - effect of magnet  asymmetry Similar effect in  Field dependent shift in 

60. June 5, 2002REU Seminar, University of Rochester59 Resolution and occupancy corrected, all data-driven Average over hits in an event Average over all events in appropriate centrality or eta bin

61. June 5, 2002REU Seminar, University of Rochester60 Large V 2 Signal compared to lower energy, closer to hydrodynamic limit implying substantial thermalization Centrality Dependence

62. June 5, 2002REU Seminar, University of Rochester61 Averaged over centrality V 2 drops for |  | > 1.5 V 2 vs 