A nuclear astrophysics experiment was performed at CRIB (CNS low-energy Radioactive-Ion Beam separator)on Mar. 2011. The goal of this experiment is to study the reaction rate of 18Ne(,p)21Na reaction, which mightbe a ...A nuclear astrophysics experiment was performed at CRIB (CNS low-energy Radioactive-Ion Beam separator)on Mar. 2011. The goal of this experiment is to study the reaction rate of 18Ne(,p)21Na reaction, which mightbe a key breakout reaction from the hot CNO cycle to rp-process in X-ray burst and nova. Yet its reaction rate ispoorly known.Explosive hydrogen burning is thought to be the main source of energy generation and a source of nucleosynthesisin X-ray burst and nova[1;2]. For example, XRBs are characterized by a sudden increase of X-ray emission withinonly a few seconds to a total energy output of about 1040 ergs, which is observed to repeat with some regularity.The recurrence time for single bursts can range from hours to days at the typical temperature of 0.4～2 GK. Thebursts have been interpreted as being generated by thermonuclear runaway on the surface of a neutron star thataccretes H- and He-rich material from a less evolved companion star in a close binary system. As shown in Fig. 1,under its typical temperature, the hydrogen burning in X-ray burst occurs from the hot CNO cycle:展开更多
The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning condi...The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.展开更多
文摘A nuclear astrophysics experiment was performed at CRIB (CNS low-energy Radioactive-Ion Beam separator)on Mar. 2011. The goal of this experiment is to study the reaction rate of 18Ne(,p)21Na reaction, which mightbe a key breakout reaction from the hot CNO cycle to rp-process in X-ray burst and nova. Yet its reaction rate ispoorly known.Explosive hydrogen burning is thought to be the main source of energy generation and a source of nucleosynthesisin X-ray burst and nova[1;2]. For example, XRBs are characterized by a sudden increase of X-ray emission withinonly a few seconds to a total energy output of about 1040 ergs, which is observed to repeat with some regularity.The recurrence time for single bursts can range from hours to days at the typical temperature of 0.4～2 GK. Thebursts have been interpreted as being generated by thermonuclear runaway on the surface of a neutron star thataccretes H- and He-rich material from a less evolved companion star in a close binary system. As shown in Fig. 1,under its typical temperature, the hydrogen burning in X-ray burst occurs from the hot CNO cycle:
基金Japan Society for the Promotion of Science(JSPS)Research(KAKENHI)(26287058)
文摘The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.
