1. Two-proton Correlation Function and Final State Interaction
Workshop on STAR TOF
Two-proton Correlation Function and Final State Interaction
Jingbo Zhang
Harbin Institute of Technology
Apr 28, Hangzhou

2. OUTLINE Motivation Two-proton Correlation Function
AMPT RHIC low energy
Pt-dependence of 2p HBT radii
Summary

3. RHIC Beam Energy Scan
Taken from P. Senger

4. Two-particle HBT Correlationxa xb pa pb

5. Excited Function of HBT Radii
The source size at different energy has contracted experimentally
from few GeV to 200GeV HIC

6. Two-proton Correlation Function
The baryon source size is
important to understand the energy density of the fireball.
q (MeV/c)
C(q)
p-p correlation
function

7. Final State Interaction (FSI)
Two-particle Correlation Function with FSI
For the two protons stand 1/4 at singlet state and 3/4 at triplet states, the modified correlation function can be written by

8. Final State Interaction (FSI)
Considering FSI (Coulumn and Strong)
FSI effects include by phase shifts
Spherical Harmonic Function

9. HBT Correlation Function
HBT Function, AMPT Au+Au

10. HBT Correlation Function (with FSI)
2πHBT, AMPT Au+Au

11. HBT Correlation Function (with FSI)
2pHBT, AMPT Au+Au

12. Pt-dependence of HBT Radii

13. Pt-dependence of HBT Radii

14. Pt-dependence of HBT Radii

15. Excited Function of 2p HBT Radii @ RHIC low energy

16. Summary
The size dimension of proton source can be contracted by HBT
Deal with the final state Interaction is the key to the two-proton HBT
Difference with pt-dependence for proton and pion source. WHY?
Critical energy scan?
by 2pHBT?
THANK YOU!