Speaker
Prof.
Toshio Suzuki
(Nihon University)
Description
Roles of nuclear weak processes in nucleosynthesis in stars and star evoultions are discussed based on recent studies on nuclear structure of both stable and unstable nuclei.
New neutrino-nucleus reaction cross sections are evaluated by using new shell-model Hamiltonians, which have proper tensor interactions and explain well the shell evolutions (change of magic numbers) toward drip-lines and spin properties of nuclei [1,2,3]. Results on $^{12}$C, $^{13}$C, $^{56}$Fe, $^{56}$Ni and $^{40}$Ar are presented, and applications to element synthesis by neutrino-processes in core-collapse supernova explosions are discussed [4,5,6,7]. Effects of $\nu$ oscillations are also duscussed [8].
Electron capture and $\beta$-decay rates in stellar environments with high densities and high temperatures are evaluated by shell-model calculations for $sd$-shell and $pf$-shell nuclei
We show that an improved evaluation of e-capture rates in Ni isotopes has been obtained [9] by a new Hamiltonian, GXPF1J, which can reproduce recent experimental data of GT strength in $^{56}$Ni [10].
The rates for URCA nuclear pairs in $sd$-shell are evaluated with USDB [11]. They are shown to provide clearly the URCA densities for A=23 and 25 and cooling of core temperatures of stars with mass 8-10 M$_{\odot}$ [12].
Finally, $\beta$-decay rates for waiting-point nuclei with $N$ =126 are evaluated by including both the Gamow-Teller and first-forbidden transitions [9]. Possible effects on r-process nucleosymthesis at A$\sim$195 are discussed.
[1] T. Suzuki, R. Fujimoto and T. Otsuka, Phys. Rev. C 67, 044302 (2003).
[2] T. Otsuka, T. Suzuki, R. Fujimoto, H. Grawe and Y. Akaishi, Phys. Rev. Lett. 95, 232502 (2005).
[3] T. Otsuka, T. Suzuki, H. Honma, Y. Utsuno, N. Tsunoda, K. Tsukiyama and M. Hjorth-Jensen, Phys. Rev. Lett. 104, 012501 (2010).
[4] T. Suzuki, S. Chiba, T. Yoshida, T. Kajino and T. Otsuka, Phys. Rev. C 74, 034307 (2006).
[5] T. Suzuki, A. B. Balantekin and T. Kajino, Phys. Rev. C 86, 015502 (2012).
[6] T. Suzuki, M. Honma, K. Higashiyama, T. Yoshida, T. Kajino, T. Otsuka, H. Umeda and K. Nomoto, Phys. Rev. C 79, 061603 (2009).
[7] T. Suzuki and M. Honma, Phys. Rev. C 87, 014607 (2013).
[8] T. Suzuki and T. Kajino, J. Phys. G: Nucl. Part. Phys. 40, 083101 (2013).
[9] T. Suzuki, M. Honma, H. Mao, T. Otsuka and T. Kajino, Phys. Rev. C 83, 044619 (2011).
[10] M. Sasano et al., Phys. Rev. Lett. 107, 202501 (2012).
[11] T. B. A. Brown and W. A. Richter, Phys. Rev. C 74, 034315 (2006); W. A. Richter, S. Mkhize and B. A. Brown, ibid. 78, 064302 (2008).
[12] H. Toki, T. Suzuk, K. Nomoto, S. Jones and R. Hirschi, Phys. Rev. C 88, 015806 (2013); S. Jones et al., Astrophys. J. 772, 150 (2913).
[13] T. Suzuki, T. Yoshida, T. Kajino and T. Otsuka, Phys. Rev. C 85, 015802 (2012).
Primary author
Prof.
Toshio Suzuki
(Nihon University)
Co-authors
Prof.
Hiroshi Toki
(RCNP, Osaka University)
Prof.
Kenichi Nomoto
(WPI, the University of Tokyo)
Prof.
Michio Honma
(University of Aizu)
Prof.
Toshitaka Kajino
(National Observatory of Japan)
