Ryohei Fukuda 1, Motoaki Saruwatari 1, Masa-aki Hashimoto 1, Shin-ichiro Fujimoto 2 1 Department of Physics, Kyushu University, Fukuoka 2 Department of Electronic Control, Kumamoto National College of Technology, Kumamoto M. Saruwatari, M. Hashimoto, R. Fukuda and S. Fujimoto, “R-process Nucleosynthesis in MHD Jet Explosions of Core-Collapse Super- novae,” Journal of Astrophysics, vol.2013, Article ID , 13pages, 2013
r-process ◦ One of the mechanisms to produce the elements heavier than Fe ◦ High entropy or low electron fraction Y e are needed. (Hoffman+1999) ◦ r-abundance pattern of r-process rich low metallicity stars : consistent with the solar one ◦ Sites : supernovae (e.g., Winteler+2012) or neutron star mergers (e.g., Korobkin+2012) Cowan & Sneden 2006
Nishimura et al ◦ Adiabatic explosion without neutrino effects ◦ R-elements distribution is almost consistent with the solar system abundances. ◦ Neutrino capture processes enhance Y e and reduce the production of r-elements? Winteler et al ◦ 3D MHD simulation with neutrino effects ◦ Abundant r-elements ◦ Short simulation time To confirm the possibility of the r-process in SNe, we performed 2D MHD simulation including neutrino effects with longer simulation time
MHD simulation ◦ ZEUS-2D code (Stone & Norman 1992) ◦ Shen EoS (Shen et al. 1998) ◦ presupernova model : 3.3 M He core (Hashimoto 1995) ◦ 0 < r < 4000 km, 0 < θ < π/2 (300 (r )×30 (θ ) grid) which covers the Fe core and inner part of Si- rich layer ◦ Including neutrino effects (leakage scheme) Nucleosynthesis calculation ◦ ~4000 nuclear species ◦ FRDM & ETFSI mass model
Model Model Model ×10 12 Model ×10 13 Model ×10 13 Model ×10 13
Model Model Model Model Model Model ×10 -3 Model 5 produces jet like explosion. Only third peak is reproduced.
We performed 2D MHD simulation of magnetorotationally driven SNe with neutrino effects using the leakage scheme. Strong jet-like explosions are obtained in model 5. We calculate nucelosynthesis inside the ejecta including the r-process. The third peak is reproduced by model 5. Supernova explosions cannot be excluded as a site of the r-process.