640 likes | 875 Views
핵물리학 입문. 부산대학교 물리학과 교수 유인권 yoo@pusan.ac.kr. Paticle Adventure RHIC Physics Introduction Heavy Ion Physics Introduction. Particle Adventure. Fundamental Particles Fundamental Interactions Standard Model Phenomenology Experiments Detector Technique.
E N D
핵물리학 입문 부산대학교 물리학과 교수 유인권 yoo@pusan.ac.kr Paticle Adventure RHIC Physics Introduction Heavy Ion Physics Introduction
Particle Adventure • Fundamental Particles • Fundamental Interactions • Standard Model • Phenomenology • Experiments • Detector Technique http://www.particleadventure.org http://nuri.pusan.ac.kr/~particleadventure
RHIC Physics Introduction • Quark • Hadrons • Quark-Gluon Plasma http://www.star.bnl.gov/~potreben/rhic.swf
Heavy Ion Physics Introduction • Motivations • Experiments Survey • Where we are • CERN-SPS situations • BNL-RHIC situations • Outlook http://nuri.pusan.ac.kr/~him : HIM in Korea
Prologue Experiment Outlook q q q q q Hadrons vs. Quark-Gluon-Plasma ? MIT Bag Model • inside of the Bag • outside of the Bag Baryon Meson • High Baryon density • High Temperature • deconfined Quarks Quark-Gluon-Plasma Introduction to Nuclear Physics
Prologue Experiment Outlook Ultra-Relativistic Heavy Ion Collision Ultra-Relativistic Quantum Molecular Dynamic Model Introduction to Nuclear Physics
Prologue Experiment Outlook System Evolution N, K, p, g, e, m, … Nuclear Collisions L, X, S, f, … Expansion Temperature Falling Hadronization End of the hadronic Interactions Freeze out Stream out Introduction to Nuclear Physics
Motivation Basic Idea A+A Collision Experiment Collision Energy ~ 10 GeV/N+N Energy Density ~ 1 GeV/fm3 Results Outlook Low Hadrons High Quark & Gluons Degree of Freedom Introduction to Nuclear Physics
Motivation Phase Transition Experiment T Results TC Outlook Q Anomalies in the Energy Dependence of the relevant observables Introduction to Nuclear Physics
Motivation Relevant Observables • Particle Production • Particle Multiplicity • Multiplicity Distribution Experiment • Varying Energy Level • Varying System Size • Particle Correlations • rel. Momentum : HBT (BEC) • Flow Results • Event-by-Event Analysis • Multiplicity Fluctuation • Charge-, pT- Fluctuation Outlook • Something else ?? Introduction to Nuclear Physics
Motivation Results Interpretation • Energy Dependence (AGS – SPS – RHIC) • Transverse Mass Spectrum Temperature • Rapidity Distribution Multiplicity • Strangeness Production • System Size Dependence (p+p, C+C, Si+Si, Pb+Pb) • Hadron Multiplicity • E-by-E Fluctuations • Outlook of NA49 Experiment Results Outlook Introduction to Nuclear Physics
Prologue Experiment Outlook Experimental Program • AGS @ BNL • Si, Au Beams • 2 ~ 15 AGeV • SIS @ GSI • Bi, Au, Ni Beams • max. 2 AGeV • SPS @ CERN • S, Pb Beams • max. 158 AGeV • RHIC @ BNL • Au Beam • 200 AGeV • LHC @ CERN • - 5.5 TeV • FAIR @ GSI • - max. 30 AGeV Introduction to Nuclear Physics
Acceleraters – Labs : BNL Since 1947 Alternating Gradient Synchrotron (AGS) 1960. 0.37c 0.997c 33GeV for protons 11GeV for AuAu The Booster synchrotron 1991 completed. Preacceleration of particles entering the AGS ring. AGS-To-RHIC (ATR) transfer line. Bunches are directed either left to the clockwise RHIC ring or right to travel counter-clockwise in the second RHIC ring. Linear Accelerator (Linac). Protons 200 MeV (300 mA) for pA collisions. Late 1960’s. Tandem Van de Graaff 1970, 15MV, Ions, 24m Tandem-to-Booster line (TTB) 1986, 700m, 0.05c Introduction to Nuclear Physics
the Broad Range Hadron Magnetic Spectrometer The Solenoidal Tracker at RHIC (STAR) Experiments @ RHIC.BNL Introduction to Nuclear Physics
LEP : 1989 LHC : 2007 1976 1959 Acceleraters – Labs : CERN Since 1954 Introduction to Nuclear Physics
Experiments @ SPS.CERN NA44 : The Focussing Spectrometer for one and two particles NA45 (CERES) : Study of Electron Pair Production in Hadron and Nuclear Collisions Large Acceptance Hadron Spectrometer NA50 : Study of Muon Pairs and Vector Mesons WA98 : Direct photons Study of Strange and Multistrange Particles Introduction to Nuclear Physics
Experiments @ LHC.CERN Introduction to Nuclear Physics
Acceleraters – Labs : GSI Gesellschaft für SchwerIonenforschung Since 1954 SIS / ESR : 216m, 0.9c, 1993 • FAIR (2012) : • Beam Intensity x 10000 • Ion Energy x 15 • Antiproton beam 15GeV • Cooled RI Beam UNILAC : 120m, 0.2c, 1985 Introduction to Nuclear Physics
Experiments @ SIS, FAIR.GSI Compressed Baryonic Matter Introduction to Nuclear Physics
NA49 @ SPS.CERN Prof. YOO, I.-K. at Pusan National University Introduction to Nuclear Physics
Prologue Experiment Outlook SuperProtonSynchrotron@CERN LEP / LHC 9 km SPS 2 km PS http://www.cern.ch Introduction to Nuclear Physics
Motivation NA49@SuperProtonSynchrotron.CERN http://na49info.cern.ch Experiment • Energy Scan : • 20, 30, 40, 80, 158 AGeV • System Scan : • pp, C+C, Si+Si, Pb+Pb Results • Elementary Reactions : • p+p, p+p, d+p, p+A Outlook Introduction to Nuclear Physics
Prologue Experiment Outlook NA49 Detector System (MTPC) Introduction to Nuclear Physics
Prologue Experiment Outlook NA49 Detector System (TOF) NIM A430 (1999) 210-244 Introduction to Nuclear Physics
Prologue Experiment Outlook NA49 Detector System (TOF) Introduction to Nuclear Physics
Prologue Experiment Outlook TPC Tracks (topview) Introduction to Nuclear Physics
Prologue Experiment Outlook TPC Tracks (3D View) Introduction to Nuclear Physics
Prologue Experiment Outlook TOF Hits (frontview) Introduction to Nuclear Physics
Prologue Experiment Outlook Particle Identification • Track Curvature Momentum • Specific dE/dx Bethe-Bloch • dE/dx PID • Time-Of-Flight & Tracklength Velocity Mass TOF PID Introduction to Nuclear Physics
Prologue Experiment Outlook minv = [(E1+E2)2-(p1+p2)2]1/2 Resonance Reconstruction • Identify secondary vertices • Examples in Pb+Pb@158AGeV Introduction to Nuclear Physics
Motivation Experiment Results Outlook pT Target (Y=0) Beam (Y=6) Rapidity vs. transv. Momentum Introduction to Nuclear Physics
Motivation Experiment Results Outlook Spectra of Strange Particles • Longitudinal direction • Rapidity : • y = 0.5ln[(E+pz)/(E-pz)] • Longitudinal expansion • Baryon stopping • Transverse direction • Transverse mass : • mT = ( pT2 + m02 )1/2 • Transverse expansion • mT-1d2N/(dmTdy) ~ exp(mT/T) Au+Au @ 1.8 AGeV Au+Au @ 200 AGeV Introduction to Nuclear Physics
Motivation mT Spectra[d2N/(mT dydmT) ~ exp(mT/T)] 20GeV 30GeV Experiment 40GeV Results 158GeV 80GeV Outlook Introduction to Nuclear Physics
Motivation Slope vs. Energy Experiment Results Outlook The Step at Elab =20 – 30 AGeV! Introduction to Nuclear Physics
Motivation Multiplicity vs. Energy Experiment Results Outlook Onset, Horn at Elab = 20-30 AGeV Introduction to Nuclear Physics
Motivation Onset of Deconfinement ? ! <p> ~ Entropy Deconfinement : An Increase of Pion Yield at the Onset Experiment Strangeness Enhancement : Hadron Gas –Mixed Phase - QGP Results Anomaly in transverse Expansion Outlook Highly Interested Region : ELab ~ 20..30 GeV/u Introduction to Nuclear Physics
PHENIX at RHIC Prof. Kang, J.H. at Yonsei University Prof. Kang's Material
FCAL The PHENIX Detector • Detector Redundancy • Fine Granularity, Mass Resolution • High Data Rate • Good Particle ID • Limited Acceptance • Charged Particle Tracking: • Drift Chamber • Pad Chamber • Time Expansion Chamber/TRD • Cathode Strip Chambers • Particle ID: • Time of Flight • Ring Imaging Cerenkov Counter • TEC/TRD • Muon ID (PDT’s) • Calorimetry: • Pb Scintillator • Pb Glass • Event Characterization: • Multiplicity Vertex Detector (Si Strip,Pad) • Beam-Beam Counter • Zero Degree Calorimeter/Shower Max Detector • Forward Calorimeter SMD/ FCAL Prof. Kang's Material
TOF PHENIX Central Arm PbSc PbGl • PID by high resolution TOF • , K < 2 GeV/c • proton, anti-proton < 4 GeV/c • = /4 • o measurement by EMCal • 1<pt<10GeV/c (possibly ~20GeV) • 6 lead- scintillator (PbSc) sectors • 2 lead- glass (PbGl) sectors • ||<0.38 at midrapidity, = Electronmeasurement • Charged tracks: DC & PC • RICH rings • EM Calorimeter clusters Prof. Kang's Material
The PHENIX Muon Arms • Detect muons with • ptot > 2 GeV/c • -1.2 > > -2.2 (South Arm) or 1.2 < < 2.4 (North Arm) • Muon Tracker (MuTr) • Measure momentum of muons with cathode-readout strip chambers at 3 stations inside Muon Magnet • Muon Identifier (MuID) • /µ separation with 5-layer sandwich of chambers (Iarocci tubes) and steel • Trigger muons Beam Pipe MuID IP Muon Magnet MuTr Prof. Kang's Material
10-15% 5-10% 0-5% Collision Centrality Determination Spectators Participants Peripheral Central • Centrality selection : Sum of Beam-Beam Counter • (BBC, |h|=3~4) and energy of Zero-degree calorimeter (ZDC) • ExtractedNcollandNpartbased on Glauber model. Prof. Kang's Material
RHIC swf http://www.star.bnl.gov/~potreben/rhic.swf Introduction to Nuclear Physics
Hard scattering in Heavy Ion collisions schematic view of jet production • Jets: • primarily from gluons at RHIC • produced early (<1fm) • sensitive to the QCD medium (dE/dx) • Observed via: • fast leading (high pt)particles or • azimuthal correlations between them Mechanisms of energy loss in vacuum (pp) is understood in terms of formation time and static chromoelectric field regeneration* . Any nuclear modification of this process could provide a hint of QGP formation. Prof. Kang's Material *F.Niedermayer, Phys.Rev.D34:3494,1986.
PHENIX RHIC Headline News… January 2002 PHENIX PRL 88, 022301 (2002) First observation of large suppression of high pT hadron yields ‘‘Jet Quenching’’? == Quark Gluon Plasma? Prof. Kang's Material
RAA : High PT Suppression to at least 10 GeV/c Peripheral AuAu - consistent with Ncoll scaling (large systematic error) Binary scaling Factor 5 Large suppression in central AuAu - close to participant scaling at high PT Participant scaling Prof. Kang's Material PRL 91 (2003) 072301
Comparison with model calculations with and without parton energy loss: Au+Au at sNN = 200 GeV without parton energy loss Levai Wang with parton energy loss Wang Vitev Levai Jet-Quenching? • Pion-suppression reproduced by models with parton energy loss • pT-dependence not well described Prof. Kang's Material
p+A (or d+A): The control experiment Proton/deuteron nucleus collision Nucleus- nucleus collision • Jet Quenching interpretation; interaction with medium produced in final state suppresses jet. • Gluon Saturation interpretation, gluons are suppressed in initial state resulting in suppression of initial jet production rate. • If these initial state effects are causing the suppression of high-PT hadrons in Au+Au collisions, we should see suppression of high-PT hadrons in d+Au collisions. Prof. Kang's Material
Centrality Dependence Au + Au d + Au Control • Opposite centrality evolution of Au+Au compared to d+Au control. • Initial state enhancement (“Cronin effect”) in d+Au is suppressed by final state effect in Au+Au. • Notice difference between p0 and h++h- (more later). Final Data Preliminary Data Prof. Kang's Material
RHIC headline news… August 2003 BNL Press Release, June 2003: Lack of high pT hadron suppression in d+Au strongly suggests that the large suppression in Au+Au is a final state effect of the produced matter (QGP?!) Prof. Kang's Material