11.07.2006R. Lednický Subatech Nantes1 Correlation Femtoscopy R. Lednický, JINR Dubna & IP ASCR...

download 11.07.2006R. Lednický Subatech Nantes1 Correlation Femtoscopy R. Lednický, JINR Dubna & IP ASCR Prague History QS correlations FSI correlations Correlation.

of 42

  • date post

  • Category


  • view

  • download


Embed Size (px)

Transcript of 11.07.2006R. Lednický Subatech Nantes1 Correlation Femtoscopy R. Lednický, JINR Dubna & IP ASCR...

  • Correlation Femtoscopy R. Lednick, JINR Dubna & IP ASCR PragueHistoryQS correlationsFSI correlations Correlation asymmetriesSummary

    R. Lednick Subatech Nantes

  • HistoryFermi34: e Nucleus Coulomb FSI in -decay modifies the relative momentum (k) distribution Fermi (correlation) factor F(k,Z,R) is sensitive to Nucleus radius R if charge Z 1measurement of space-time characteristics R, c ~ fmCorrelation femtoscopy :of particle production using particle correlations

  • Fermi factor in -decay= |-k(r)|2 ~ (kR)-(Z/137)2Z=83 (Bi)-+R=842 fm

  • 2xGoldhaber, Lee & PaisGGLP60: enhanced ++ , -- vs +- at small opening angles interpreted as BE enhancement depending on fireball radius R0R0 = 0.75 fm p p 2+ 2 - n0

  • Kopylov & PodgoretskyKP71-75: settled basics of correlation femtoscopy

    in > 20 papers proposed CF= Ncorr /Nuncorr & mixing techniques to construct Nuncorr clarified role of space-time characteristics in various models noted an analogy Grishin,KP71 & differences KP75 withHBT effect in Astronomy (see also Shuryak73, Cocconi74)

  • QS symmetrization of production amplitude particle momentum correlations are sensitive to space-time structure of the source CF=1+(-1)Scos qx

    p1 p2x1 x2q = p1- p2 , x = x1- x2nnt , t, nns , s210 |q|1/R0total pair spin2R0 KP71-75exp(-ip1x1)

  • Intensity interferometry of classical electromagnetic fields in Astronomy HBT56 product of single-detector currentscf conceptual quanta measurement two-photon countsp1p2x1x2x3x4stardetectors-antennas tuned to mean frequency Correlation ~ cos px34

    p-1| x34 |Space-time correlation measurement in Astronomy source momentum picture p= star angular radius orthogonal tomomentum correlation measurement in particle physics source space-time picture x

    KP75 no info on star R,

  • HBT paraboloid mirrors focusing the light from a star on photomultipliersMeasured product ST of electric currents from the two photomultipliers integrated during time T ~ hours andstudied ST / ST2- ST 2 vs mirror distance d

  • ST / ST2- ST 2 Normalized to 1 at d=0Ne ~ 108 e/sec, f ~ 1013 Hz, fF ~ 5-45 MHzRequired T ~ (2 /Ne)2/F ~ hoursHBT measurement of the angular size of Sirius

  • momentum correlation (GGLP,KP) measurements are impossiblein Astronomy due to extremely large stellar space-time dimensions space-time correlation (HBT) measurements can be realized

    also in Laboratory:whilePhillips, Kleiman, Davis67:linewidth measurement from a mercurury discharge lamp900 MHzt nsecGoldberger,Lewis,Watson63-66Intensity-correlation spectroscopy Measuring phase of x-ray scattering amplitude & spectral line shape and widthFetter65Glauber65

  • GGLP60 data plotted as CFR0~1 fmp p 2+ 2 - n0

  • Examples of present data: NA49 & STAR zxyCorrelation strength or chaoticityNA49Interferometry or correlation radiiKKSTAR Coulomb corrected3-dim fit: CF=1+exp(-Rx2qx2 Ry2qy2 -Rz2qz2 -2Rxz2qx qz)

  • General parameterization at |q| 0Particles on mass shell & azimuthal symmetry 5 variables:q = {qx , qy , qz} {qout , qside , qlong}, pair velocity v = {vx,0,vz} Rx2 = (x-vxt)2 , Ry2 = (y)2 , Rz2 = (z-vzt)2

    q0 = qp/p0 qv = qxvx+ qzvz

    y sidex out transverse pair velocity vtz long beamPodgoretsky83; often called cartesian or BP95 parameterization Interferometry or correlation radii:cos qx=1- (qx)2 exp(-Rx2qx2 Ry2qy2 -Rz2qz2 -Rxz2qx qz)Grassberger77RL78

  • Probing source shape and emission duration Static Gaussian model with space and time dispersions R2, R||2, 2 Rx2 = R2 +v22 Ry2 = R2 Rz2 = R||2 +v||22 Emission duration2 = (Rx2- Ry2)/v2 Rside2 fm2If elliptic shape also in transverse plane RyRside oscillates with pair azimuth fRside (f=90) smallRside (f=0) largezABOut-of reaction planeIn reaction planeIn-planeCircularOut-of planeKP (71-75)

  • Probing source dynamics - expansionDispersion of emitter velocities & limited emission momenta (T) x-p correlation: interference dominated by pions from nearby emitters Interferometry radii decrease with pair velocity Interference probes only a part of the sourceResonances GKP71 ..Strings Bowler85 ..HydroPt=160 MeV/cPt=380 MeV/cRoutRsideRoutRsideCollective transverse flow F RsideR/(1+mt F2/T)

    Longitudinal boost invariant expansionduring proper freeze-out (evolution) time Rlong (T/mt)/coshyPratt, Csrg, Zimanyi90Makhlin-Sinyukov87}1 in LCMS..Bertch, Gong, Tohyama88Hama, Padula88Mayer, Schnedermann, Heinz92Pratt84,86Kolehmainen, Gyulassy86

  • AGSSPSRHIC: radii STAR Au+Au at 200 AGeV 0-5% central Pb+Pb or Au+Au Clear centrality dependence Weak energy dependence

  • AGSSPSRHIC: radii vs pt Rlong: increases smoothly & points to short evolution time ~ 8-10 fm/c

    Rside , Rout :change little & point to strong transverse flow t ~ 0.4-0.6 &short emission duration ~ 2 fm/cCentral Au+Au or Pb+Pb

  • Interferometry wrt reaction planeSTAR data: oscillations like for astatic out-of-plane sourcestronger then Hydro & RQMDShort evolution timeOut-of-planeCircularIn-planeTimeTypical hydro evolution STAR04 Au+Au 200 GeV 20-30% p+p+ & p-p-

  • Expected evolution of HI collision vs RHIC datahadronizationinitial statepre-equilibriumQGP andhydrodynamic expansionhadronic phaseand freeze-outdN/dt1 fm/c5 fm/c10 fm/c50 fm/ctimeKinetic freeze outChemical freeze outRHIC side & out radii: 2 fm/cRlong & radii vs reaction plane: 10 fm/cBass02

  • Puzzle ? 3D Hydro2+1D Hydro1+1D Hydro+UrQMD(resonances ?)But comparing1+1D H+UrQMDwith 2+1D Hydro kinetic evolutionat small pt& increases Rside~ conserves Rout,Rlong Good prospect for 3D HydroHydro assuming ideal fluid explains strong collective () flows at RHIC but not the interferometry results+ hadron transportBass, Dumitru, ..Huovinen, Kolb, ..Hirano, Nara, ..? not enough F + ? initial F

  • Why ~ conservation of spectra & radii? qxi qxi +q(p1+p2)T/(E1+E2) = qxiSinyukov, Akkelin, Hama02: free streaming also in real conditions and thusinitial interferometry radiiti= ti +T, xi = xi + vi T , vi v =(p1+p2)/(E1+E2)

    Based on the fact that the known analytical solutionof nonrelativistic BE with spherically symmetricinitial conditions coincides with free streamingone may assume the kinetic evolution close to~ conserving initial spectra and ~ justify hydro motivated freezeout parametrizations Csizmadia, Csrg, Lukcs98

  • Checks with kinetic modelAmelin, RL, Malinina, Pocheptsov, Sinyukov05: System cools & expands but initial Boltzmann momentum distribution & interferomety radii are conserved due to developed collective flow ~ ~ tens fm = = 0in static modelin kinetic model123

  • Hydro motivated parametrizationsKniege05BlastWave: Schnedermann, Sollfrank, Heinz93Retiere, Lisa04

  • BW fit ofAu-Au 200 GeVT=106 1 MeV = 0.571 0.004 c = 0.540 0.004 cRInPlane = 11.1 0.2 fmROutOfPlane = 12.1 0.2 fmLife time (t) = 8.4 0.2 fm/cEmission duration = 1.9 0.2 fm/cc2/dof = 120 / 86Retiere@LBL05Rz=z/x=0(r/R)

  • Other parametrizationsBuda-Lund: Csanad, Csrg, Lrstad04 Similar to BW but T(x) & (x)hot core ~200 MeV surrounded by cool ~100 MeV shellDescribes spectra, radii, v2()Krakow: Broniowski, Florkowski01Describes spectra, radii but RlongSingle freezeout model + Hubble-like flow + resonances Kiev-Nantes: Borysova, Sinyukov, Erazmus, Karpenko05closed freezeout hypersurfaceGeneralizes BW using hydro motivatedAdditional surface emission introducesx-t correlation helps to desribe Routat smaller flow velocityvolume emissionsurface emission? may account for initial F Fit points to initial 0F of ~ 0.3

  • Final State InteractionSimilar to Coulomb distortion of -decay Fermi34:e-ikr -k(r) [ e-ikr +f(k)eikr/r ]eicAcF=1+ _______ + kr+krkaCoulombs-wavestrong FSIFSIfcAc(G0+iF0)}}Bohr radius}Point-likeCoulomb factor k=|q|/2CFnnppCoulomb only |1+f/r|2 FSI is sensitive to source size r and scattering amplitude fIt complicates CF analysis but makes possible Femtoscopy with nonidentical particles K, p, .. & Study relative space-time asymmetries delays, flow Study exotic scattering , K, KK, , p, , ..Coalescence deuterons, ..|-k(r)|2Migdal, Watson, Sakharov, Koonin, GKW, ...

  • FSI effect on CF of neutral kaonsSTAR data on CF(KsKs)Goal: no Coulomb. But R may go up by ~1 fm if neglected FSI in l = 0.9 0.2R = 4.1 0.5 fm 5.3 0.6 fmKK (~50% KsKs) f0(980) & a0(980)RL-Lyuboshitz82 tLyuboshitz-Podgoretsky79: KsKs from KK also show BE enhancement

  • NA49 central Pb+Pb 158 AGeV vs RQMDLong tails in RQMD: r* = 21 fm for r* < 50 fm 29 fm for r* < 500 fmFit CF=Norm [Purity RQMD(r* Scaler*)+1-Purity]Scale=0.76Scale=0.92Scale=0.83 RQMD overestimates r* by 10-20% at SPS cf ~ OK at AGS worse at RHIC p

  • p CFs at AGS & SPS & STARFit using RL-Lyuboshitz82 with consistent with estimated impurityR~ 3-4 fm consistent with the radius from pp CF Goal: No Coulomb suppression as in pp CF &Wang-Pratt99 Stronger sensitivity to R=0.50.2R=4.50.7 fmScattering lengths, fm: 2.31 1.78Effective radii, fm: 3.04 3.22singlet tripletAGSSPSSTARR= fm

  • mt scaling transverse flow, K, p, radii show mt scaling expected in hydrodynamicspp KsKs

  • Correlation study of particle interaction-+& & p scattering lengths f0 from NA49 and STARNA49 CF(+) vs RQMD with SI scale: f0 sisca f0 (=0.232fm)sisca = 0.60.1 compare ~0.8 fromSPT & BNL data E765 K e Fits using RL-Lyuboshitz82 NA49 CF() data prefer |f0()| f0(NN)