The $^{150}$Nd($^3$He,$t$) and $^{150}$Sm($t$,$^3$He) reactions with applications to $ββ$ decay of $^{150}$Nd
C. J. Guess, T. Adachi, H. Akimune, A. Algora, Sam M. Austin, D. Bazin, B. A. Brown, C. Caesar, J. M. Deaven, H. Ejiri, E. Estevez, D. Fang, A. Faessler, D. Fre… 展开作者
C. J. Guess, T. Adachi, H. Akimune, A. Algora, Sam M. Austin, D. Bazin, B. A. Brown, C. Caesar, J. M. Deaven, H. Ejiri, E. Estevez, D. Fang, A. Faessler, D. Frekers, H. Fujita, Y. Fujita, M. Fujiwara, G. F. Grinyer, M. N. Harakeh, K. Hatanaka, C. Herlitzius, K. Hirota, G. W. Hitt, D. Ishikawa, H. Matsubara, R. Meharchand, F. Molina, H. Okamura, H. J. Ong, G. Perdikakis, V. Rodin, B. Rubio, Y. Shimbara, G. Süsoy, T. Suzuki, A. Tamii, J. H. Thies, C. Tur, N. Verhanovitz, M. Yosoi, J. Yurkon, R. G. T. Zegers, J. Zenihiro
The $^{150}$Nd($^3$He,$t$) reaction at 140 MeV/u and $^{150}$Sm($t$,$^3$He) reaction at 115 MeV/u were measured, populating excited states in $^{150}$Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) $ββ$ decay of $^{150}$Nd to $^{150}$Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of Quasiparticle Random-Phase Approximation (QRPA), which is one of the main methods employed for estimating the half-life of the neutrinoless $ββ$ decay ($0νββ$) of $^{150}$Nd. The present results thus provide useful information on the neutrino responses for evaluating the $0νββ$ and $2νββ$ matrix elements. The $2νββ$ matrix element calculated from the Gamow-Teller transitions through the lowest $1^{+}$ state in the intermediate nucleus is maximally about half of that deduced from the half-life measured in $2νββ$ direct counting experiments and at least several transitions through $1^{+}$ intermediate states in $^{150}$Pm are required to explain the $2νββ$ half-life.
Because Gamow-Teller transitions in the $^{150}$Sm($t$,$^3$He) experiment are strongly Pauli-blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the $2\hbarω$, $ΔL=0$, $ΔS=1$ isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.
A proposed direct measurement of cross section at Gamow window for key reaction $^{19}$F($p$,$α$)$^{16}$O in Asymptotic Giant Branch stars with a planned accelerator in CJPL
Relevant energy ranges for astrophysical reaction rates
利用理论截面计算了质子-中子滴注线10 ≤ Z ≤ 83靶上（p，gamma），（p，n），（p，alpha），（alpha，gamma），（alpha，n），（alpha，p），（n，gamma），（n，p），（n，alpha）的天体物理反应速率的有效能量窗（Gamow窗）。结果表明，广泛使用的近似公式的相关能量范围是无效的大量的反应有关的流体静力学和爆炸核合成。讨论了平均宽度的能量依赖性对伽莫夫窗口位置的影响，并以表格形式给出了结果（也在http：//download.nucastro.org/astro/gamow/）。
Ab initio studies of double Gamow-Teller transition and its correlation with neutrinoless double beta decay
利用手征相互作用和几种{ \em ab initio}方法计算了一系列同位素基态到基态的双Gamow-Teller跃迁的核矩阵元，并探讨了这些核矩阵元与轻Majorana中微子交换产生的无中微子双β衰变的核矩阵元之间的相关性.当我们考虑了{ \em ab initio}计算的所有同位旋守恒跃迁和同位旋变化跃迁的NME时，我们得到了很强的相关性.然而，对于实验相关的同位旋变化跃迁本身，相关性较弱，可能无助于减少无中微子双β衰变的NME的不确定性。
Advancement of Photospheric Radius Expansion and Clocked Type-I X-Ray Burst Models with the New $^{22}$Mg$(α,p)^{25}$Al Reaction Rate Determined at Gamow Energy
Double Gamow-Teller transitions and its relation to neutrinoless $ββ$ decay
本文采用最先进的大尺度核壳模型计算方法研究了$^{48}$ Ca的双Gamow-Teller（DGT）强度分布。分析表明，DGT巨共振的质心能量主要取决于等矢量对相互作用，而共振宽度则对等oscillation对相互作用更为敏感。配对关联在无中微子$ββ$（$0νββ$）衰变中也很关键。我们发现$^{48}$ Ca DGT巨共振的质心能量和宽度与$0νββ$衰变核矩阵元的%值之间有一个简单的关系。更一般地说，我们观察到一个非常好的线性相关性之间的DGT过渡到基态的最终核和$0νββ$衰变矩阵元素。的相关性，这起源于占主导地位的短程字符的两个过渡，延伸到较重的系统，包括几个$ββ$发射器，并在能量密度泛函的结果也持有。我们的研究结果表明，DGT实验可以是一个非常有价值的工具，以获得信息的价值$0νββ$衰变核基质元素。
Ab initio calculations of two-neutrino and neutrinoless double-$\boldsymbolβ$ decay of $^{48}$Ca and related Gamow-Teller strength distributions
Technische Universität Darmstadt（达姆施塔特工业大学）；ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH（GSI重离子研究中心极端物质研究所(EMMI)）；Max-Planck-Institut für Kernphysik（马克斯·普朗克核物理研究所）
Systematic study of proton radioactivity based on Gamow--like model with a screened electrostatic barrier
本文基于带屏蔽静电势垒的类伽莫夫模型，系统地研究了$51 \leq Z \leq 83$核的质子放射性半衰期。在考虑库仑势与Hulthen势屏蔽静电效应时，该模型有两个参数，即有效核半径参数r_0和屏蔽参数a。计算结果与实验数据吻合较好。此外，我们扩展这个模型来预测质子放射性半衰期的16个核在同一区域内的一个因素为2.94，其质子放射性能量允许或观察到，但尚未量化。同时，利用一种普适衰变规律对质子放射性半衰期进行了研究。结果表明，在轨道角动量相同的情况下，计算的半衰期与库仑参数呈线性关系。
Simultaneous Measurements of the Beta Neutrino Angular Correlation in $^{32}$Ar Pure Fermi and Pure Gamow-Teller Transitions using Beta-Proton Coincidences
Indirect Measurement of the $\rm S^*(E)$ Factor for $\rm {}^{12}C({}^{12}C,\mathit{p}){}^{23}Na$ at Gamow Energies via the Trojan Horse Method with Near-0 degree Spectator Detection
Institute of Radiation Technology, Beijing Academy of Science and Technology（北京应用技术研究院辐射技术研究所）
