论文标题
核较弱的速率和恒星中的核过程
Nuclear Weak Rates and Nuclear Weak Processes in Stars
论文作者
论文摘要
恒星环境中的核弱速率是通过壳模型计算获得的，包括游戏机 - 泰勒（GT）和自旋 - 偶极转变，并应用于恒星中的核弱过程。指出了准确的弱率研究天体物理过程的重要作用。 $ SD $ -SHELL中的弱点用于研究以8-10 m $ _ {\ odot} $的恒星中Onemg内核的演变。研究了核URCA工艺对核心的冷却，并研究了$^{20} $ ne的双电子船船的供暖。尤其是，使用$^{20} $ ne中第二验证过渡的电子捕获率通过walecka和Behrens-b $ \ ddot {\ mbox {\ mbox {u}} $ hring的多极扩展方法进行评估，并讨论了核心的最终命运，核心散发或热核爆炸爆炸。 $ PF $壳中的弱速率应用于IA型超新星中铁组元素的核合成。与太阳丰度相比，富含中子的铁同位素的生产过量问题现在降低到两个因素。通过扩展的kuo-krenciglowa方法获得的有效相互作用，评估了反转岛上$ $ = 31的核urca对的较弱率。 $^{78} $ ni中的过渡强度和电子捕获率对核心爆发过程很重要，并使用$ PF $ - $ SDG $ shell评估，并将其与随机相位相关的随机相关率和有效的速率公式进行了比较。 $β$ -DECAY的$ n $ = 126个异酮通过GT和首次验证过渡进行了评估。发现半衰期比标准模型获得的短。 $^{13} $ c，$^{16} $ o和$^{40} $ ar的中微子 - 核反应横截面是用新的Shell-Model Hamiltonians获得的。讨论了对核合成，中微子检测，中微子振荡和中微子质量层次结构的影响。
Nuclear weak rates in stellar environments are obtained by shell-model calculations including Gamow-Teller (GT) and spin-dipole transitions, and applied to nuclear weak processes in stars. The important roles of accurate weak rates for the study of astrophysical processes are pointed out. The weak rates in $sd$-shell are used to study the evolution of ONeMg cores in stars with 8-10 M$_{\odot}$. Cooling of the core by nuclear Urca processes, and the heating by double e-captures on $^{20}$Ne are studied. Especially, the e-capture rates for a second-forbidden transition in $^{20}$Ne are evaluated with the multipole expansion method of Walecka and Behrens-B$\ddot{\mbox{u}}$hring, and the final fate of the cores, core-collapse or thermonuclear explosion, are discussed. The weak rates in $pf$-shell are applied to nucleosynthesis of iron-group elements in Type Ia supernovae. The over-production problem of neutron-rich iron isotopes compared with the solar abundances is now reduced to be within a factor of two. The weak rates for nuclear Urca pair with $A$=31 in the island of inversion are evaluated with the effective interaction obtained by the extended Kuo-Krenciglowa method. The transition strengths and e-capture rates in $^{78}$Ni, important for core-collapse processes, are evaluated with the $pf$-$sdg$ shell, and compared with those obtained by the random-phase-approximation and an effective rate formula. $β$-decay rates of $N$ =126 isotones are evaluated with both the GT and first-forbidden transitions. The half-lives are found to be shorter than those obtained by standard models. Neutrino-nucleus reaction cross sections on $^{13}$C, $^{16}$O and $^{40}$Ar are obtained with new shell-model Hamiltonians. Implications on nucleosynthesis, neutrino detection, neutrino oscillations and neutrino mass hierarchy are discussed.
