Download
1 / 14
140 likes | 217 Views
F reeze-out information and light nucleus production. in relativistic heavy-ion collisions. ( INPAC and Department of Physics and Astronomy, Shanghai Jiao Tong University. sunkaijia@sjtu.edu.cn ). Kaijia Sun( 孙开佳 ). Advisor: Lie-wen Chen ( 陈列文 ). 2013 08 09. outline.
E N D
Freeze-out information and light nucleus production in relativistic heavy-ion collisions (INPAC and Department of Physics and Astronomy, Shanghai Jiao Tong University. sunkaijia@sjtu.edu.cn) Kaijia Sun(孙开佳) Advisor: Lie-wen Chen (陈列文) 2013 08 09
outline • 1. Retière-Lisa model • Transverse momentum distribution, • Freeze-out information • 2. Coalescence model • Wigner function : a semi-classical method to • calculate coalescence probability of multiple particles 3. Yields of Light nucleus, Hypertriton, and di-Lambda 4. Summary and outlook
Basic hypothesis z y x • Local Thermal Equilibrium • Longitudinal boost invariance • Freeze-out in momentum space Physical variables: Temperature T Radial flow(rapidity) Size τ0 R02 Number density n orFugacityξ (Form factor as) J.D.Bjorken, Phys.Rev.D27, 140(1983)
Retière-Lisa Model Parameterization of transverse flow One particle invariant distribution Covariant distribution function Fred Cooper and Graham Frye, Phys. Rev D. 10, 186 (1974) FabriceRetière et.al, PRC70, 044907(2004)
Freeze-out Information Spectrum of proton , centrality 0~5% The PHENIX Collaboration, Phys. Rev.C. 69, 034909 (2004) Parameters : Temperature T =0.1115(GeV) Radial flow =0.978Size τ0 R02ξ=104.2 (Form factor as=0) <>=1.02 GeV In preparation Sun and Chen
Phase space distribution Statistical factor Wigner function Invariant phase factor Covariant Coalescence model Dover/Heinz/Schnedermann/Zimanyi, PRC44, 1636 (1991) • The structure of freeze-out space-time • Neglecting binding energy • coalescence probability : Wigner function
Wigner phase-space density for t/3He Assume nucleon wave function in t/3He can be described by the harmonic oscillator wave function, i.e., t/3He Wigner phase-space density and root-mean-square radius: RMS radius is the only parameter determining wignerfunction !
Light nucleus spectrum In preparation Sun and Chen Fugacityξ= 8.3 Sizeτ0= 9.9 (fm/c) R0 =18.0 （fm） (The PHENIX Collaboration), Phys. Rev. C. 69, 034909 (2004) (The STAR Collaboration), Phys. Lett.B. 655, 104(2007) (The STAR Collaboration), Phys. Rev.Lett. 108, 072301(2004) (The STAR Collaboration), arXiv:0909.0566[nucl-ex]
Yields of light nucleus In preparation Sun and Chen H. Agakishiev, et al. (Star Collaboration) Nature473 (2011) 353 . L.Xue and Y.G.Ma, et al. PRC85,064912. 2012
Ratio In preparation Sun and Chen A.Andronic, P.Braun-Munzinger,J.Stchel, Phys. Lett.B. 673, 142-145 (2009) A.Andronic, P.Braun-Munzinger,J.Stchel, H.Stcker, Phys. Lett.B. 697, 203-207 (2011)
Physics with strangeness Signal for QGP Test QCD and Nature of nuclear force De-confined Phase transition
Yields of Hypertriton and Di-Lambda with S=-2 He3=12.9E-5 D=0.086 In preparation Sun and Chen H. Garcilazo et.al, PRL 012503(2013)
Summary and outlook Parameters: Temperature T =0.1115 （GeV） Radial flow =0.978 Size τ0=9.9(fm/c) R0 =18.0 （fm） Fugacityξ = 8.3 (Form factor as=0) • Coalescence model is a useful tool to describe the light nucleus production at relativistic HIC’s and extract freeze-out information • H-dibaryon yield at RHIC is between that of d and 3He • It is interesting to see the HBT correlation….. • This method is easy to extend to quark level to investigate hardronization
