Oct. 16 th, 2015, Yonsei

RAON 2

Far from Stability Line 3

4 Capture b<b c Quasi-fission Compound Nucleus Fast-fission L B <L<L cap Inelastic b>b c scattering Fusion 0<L<L B Projectile Target A few MeV/n Fission (Fusion-fission) n p α Evaporation Competition!

Comparison with Experimental Data 5 The experimental data for reactions forming super heavy nuclei 116 and 118 with 48 Ca beam (at JINR in Dubna)

ER Cross-sections 6 58 Fe Th 64 Ni Th The maximum values in both reactions are ~1 fb for 4n ER cross-section.

Entrance Channel 7

8

Quantum Molecular Dynamics 9 RAON  Exotic beam at low and intermediate energies Effect of nuclear structure is important in these energies. Some transport model codes (AMD, CoMD, …) are available, but they are still not good enough to describe rare isotope beam. Good event generator for RAON is needed for both theoretical and experimental purposes. Transport model : Model to treat non-equilibrium aspects of the temporal evolution of a collision. QMD (Quantum Molecular Dynamics) model Many-body problem with nucleons Numerical simulation (event generator) Early time region in a collision Different methods with different energies

Transport Model 10 d > 1.5 fm Gaussian w.f. Check stability! Projectile Target N-N collisions! 40 Ca N-N potential! Disconnected if a length is larger than 5 fm. Second de-excitation : GEMINI, …

Propagation 11 Skyrme parametrization for NN potential Ref.) M. Papa PRC 64(2010)024612

N-N Collision 12 b r1r1 r2r2 In our model, If a distance, d, between two nucleons is smaller than b, d<b, a collision is always tried. Occupation number After a nucleon-nucleon collision, we calculate the 6-dim. phase space density for each nucleon. If this condition for any nucleon is not satisfied, that collision will be blocked by the Pauli principle.

Central and Peripheral Collisions 13

Central and Peripheral Collisions 14

Central Collision 15 Preliminary 40 Ca + 9 Be Elab = 140 MeV/n Total : 2000 events Impact parameter: 1~4 fm

Summary and Outlook 16  RAON will give a chance to explore far from the stability line  Near coulomb barrier energies, fusion reaction is expected. Using fusion reaction, we can synthesize a new element.  Transport model is important to simulate heavy-ion collisions. And a QMD-type model is appropriate for event generator.  To simulate and to predict experimental data at RAON, we need to implement more precise fermionic nature of nucleons in the code. Also, many exotic structures of neutron-rich nuclei need to be considered.

Thank you for your attention!!