Hadronization by coalescence plus fragmentation from RHIC to LHC

Transcription

1 Vincenzo Minissale University of Catania INFN LNS Hadronization by coalescence lus fragmentation from RHIC to LHC Nucleus Nucleus 015, June 015 Vincenzo Greco Francesco Scardina arxiv:

2 Outline Hadronization: Coalescence Fragmentation Coalescence model and Parameters Comarison with data RHIC Au+Au s = 00 GeV LHC Pb+Pb s =.76 ev Ellitic Flow 1

3 Ultrarelativistic heavy-ion collisions HIC sequence Initial Stage Pre-equilibrium stage Exansion QGP Hadronization Chemical and kinetic freeze-out

4 Ultrarelativistic heavy-ion collisions HIC sequence Initial Stage Pre-equilibrium stage Exansion QGP Hadronization Chemical and kinetic freeze-out

5 Hadronization Fragmentation dn d h h dn f dz d f f D f h ( Fragmentation Function b z ) 0 < z < 1 d c a hadrons S. Albino, B.A. Kniehl, G. Kramer, Nucl.Phys. B803 (008) 3

6 Hadronization Fragmentation dn dn h f dz d h f d Coalescence f D f h ( Fragmentation Function b z ) 0 < z < 1 d c a hadrons R. Fries, B. Muller, C. Nonaka, and S. Bass, Phys.Rev.Lett. 90, 0303 (003) V. Greco, C. Ko, and P. Levai, Phys.Rev. C68, (003) 3

7 Fragmentation dn dn h f dz d h f d Coalescence dn d f Hadronization D f h Fragmentation Function b ( z ) 0 < z < 1 3 σ d i id i f (, ) ( 1...,... 3 q xi i fh x xn (π) 1 c a d hadrons n H g )δ( H n i i1 ) Parton Distribution Function Statistical factor colour-sin-isosin Hadron Wigner Function 3

8 Fragmentation dn dn h f dz d h f d Coalescence dn d f Hadronization D f h ( z ) 3 σ d i id i f (, ) ( 1...,... 3 q xi i fh x xn (π) 1 b d c a hadrons n H g )δ( H n i i1 Parton Distribution Function Statistical factor colour-sin-isosin f M 9π Hadron Wigner Function ( x x ) ( ) ( m m ) x 1 Fragmentation Function 0 < z < ) x = 1/ free arameter 3

9 Ratio RHIC Observables Proton to ion ratio Enhancement In the vacuum, from fragmentation functions the ratio is D D c c ( z) ( z) 0.5 Ellitic Flow Slitting ransverse momentum 4

10 RHIC Observables Proton to ion ratio Enhancement In the vacuum, from fragmentation functions the ratio is D D c c ( z) ( z) 0.5 Ellitic Flow Slitting 4

11 Coalescence code Consider i articles Give a robability P i from the artonic distribution Comute the coalescence integral 5 ), ;, ( ) ( ) ( ) ( (), j i j i M j i j i q q M M x x f j P i P g d dn

12 Fireball arameters Central collision (0-10%) emerature = 160 MeV Collective flow β = β max r β max from radial exansion R = R 0 + β max axτ Uniform in x, y ; z = τ sinh y V = πr τ Fireball radius+radial flow constraints R Fireball transverse radius dn ch dy ; de dy 6

13 Fireball arameters Central collision (0-10%) emerature = 160 MeV Collective flow β = β max r R β max from radial exansion R = R 0 + β max axτ Uniform in x, y ; z = τ sinh y V = πr τ Fireball radius+radial flow constraints yical QGP lifetime RHIC = 4.5 fm/c LHC = 7.8 fm/c dn ch dy ; de dy 6

14 Fireball arameters Central collision (0-10%) emerature = 160 MeV Collective flow β = β max r R β max from radial exansion R = R 0 + β max axτ Uniform in x, y ; z = τ sinh y V = πr τ Fireball radius+radial flow constraints R = 8.7 fm at RHIC R = 10. fm at LHC 1000 fm 3 RHIC 500 fm 3 LHC yical QGP lifetime RHIC = 4.5 fm/c LHC = 7.8 fm/c dn ch dy β max = 0.37 at RHIC β max = 0.63 at LHC ; de dy 6

15 hermal Distribution (< GeV) Minijet Distribution (> GeV) m m g d r d dn q q q q q ) ( ex ) ( 3,, n jet B B A d dn A A jet A A A A d dn RHIC LHC Parton Distibution 7

16 Resonance Decay π (I = 1, J = 0) k I = 1, J = 1/ kπ ρ I = 1, J = 1 ππ I = 3/, J = 3/ Nπ Suression factor (I = 1/, J = 1/) I = 3/, J = 3/ Nπ m H m H 3/ e E H E H k ± (I = 0, J = 1/) k I = 1, J = 1/ kπ Λ 1116 (I = 0, J = 1/) Σ I = 1, J = 1/ Λγ Λ 1405 I = 0, J = 1/ Σπ Σ I = 1, J = 3/ Λπ with B. R. = 88% Σπ with B. R. = 11,7% 8

17 Results RHIC

18 RHIC - Pion 9

19 RHIC - Antiroton 10

20 RHIC Kaon & Lambda 11

21 RHIC - Ratios 1

22 Results LHC

23 LHC - Pion 13

24 LHC - Proton 14

25 LHC Kaon & Lambda 15

26 LHC - Ratios Height and osition of the eak well described. Lack of fragmentation at 6 GeV (seen also in with AKK) Soft-minijet coalesc. contribution around and above the eak (similar to EPOS) Only colaescence would give higher eak shifted in Without radial flow ( collisions but not exactly) 16

27 RHIC Observables Ellitic Flow slitting 17

28 Ellitic Flow Fourier exansion of the azimuthal distribution f φ, = 1 + v n cos nφ n=1 n= Ellitic flow momentum anisotroy in the transverse lane coalescence brings to v,m ( ) v,q ( /) Partonic ellitic flow v,b ( ) 3v,q ( /3) Hadronic ellitic flow 18

29 Ellitic Flow Fourier exansion of the azimuthal distribution f φ, = 1 + v n cos nφ n=1 n= Ellitic flow momentum anisotroy in the transverse lane coalescence brings to v,m ( ) v,q ( /) Partonic ellitic flow v,b ( ) 3v,q ( /3) Hadronic ellitic flow 0

30 Preliminary on radial flow imact Same aroach, but with an anisotroic radial flow in the quark distrib. function d dn r d g m ( ) 3 ( m ex ) ( r, ) 0( r) ( r)cos( ) About 0% quark number scaling breaking : - 3D - finite width wave function - anisotroic radial flow 19

31 Summary Good agreement with RHIC & LHC data π,, k, Λ sectra ratio eak shift at LHC with no arameters change v QNS breaking Outlooks other articles (ϕ, Ξ,Ω) other centrality Next order in v n and effect of radial flow on the Quark Number Scaling

32 Backu slides

33 Ellitic Flow and v 3 Fourier exansion of the azimuthal distribution f φ, = 1 + v n cos nφ n=1 n= Ellitic flow momentum anisotroy in the transverse lane Fluctuations n=3 0

34 Next order: v 3 - LHC 1

35 * What s the aroach working in the range -10 GeV? * Is the coalescence necessary? EPOS= (half)-viscous-hydro + soft-jet recombination K. Werner, PRL109 (01) /? - v of L and K? - Also sectra check

36 Prediction for at LHC - Preliminary We do not have the fragm. function for It is clear that coalescence redict a similar sloe for and / Soft art same sloe and Missing fragmentation Contribution usually half of the yield at 4 GeV

37 e In case of a artonic thermal distribution f Ae th e / / / for a two-quark hadron, e xp / e (1 x) P / 1 e P / in the n quark case n P 1 P n n e n / e Baryon/Meson Ratio = 1 e Parton sectrum Baryon Meson H 4