论文标题
与Sonik的3HE+4HE的弹性散射
Elastic scattering of 3He+4He with SONIK
论文作者
论文摘要
为了改善4HE（3HE，G）7BE的理论模型的约束，对3HE和4HE的弹性散射横截面的测量很重要，这是大爆炸核合成和太阳中微子产生的关键反应。该反应的天体物理S因子是7BE和8B太阳中微子通量的标准太阳模型预测的重要不确定性来源。文献中报道的弹性散射测量值不会扩展到低能量，并且缺乏适当的不确定性定量。在质量中心能量EC.M.中进行了4HE（3HE，3HE）4HE反应的新测量。 = 0.38-3.13 MEV使用核在反运动室（SONIK）散射室中的散射：一个无窗的，延伸的气体目标，周围环绕着位于Triumf的30个准直的带电粒子探测器的阵列。这是3HE+4HE的第一个弹性散射测量，比以前的测量值更大，角度范围更大，精度更高。使用R-Matrix和Halo有效场理论（Halo EFT）框架分析了弹性散射数据，并提取了S波散射长度和有效范围的值。在低能量下，对S波有效范围功能的知识的提高将减少太阳能下S34的总体不确定性。
Measurements of the elastic scattering cross section of 3He and 4He are important in order to improve constraints on theoretical models of 4He(3He,g)7Be, a key reaction in Big Bang nucleosynthesis and solar neutrino production. The astrophysical S-factor for this reaction is a significant source of uncertainty in the standard solar-model prediction of the 7Be and 8B solar neutrino fluxes. The elastic scattering measurements reported in the literature do not extend to low energies and lack proper uncertainty quantification. A new measurement of the 4He(3He,3He)4He reaction has been made at center-of-mass energies Ec.m. = 0.38-3.13 MeV using the Scattering of Nuclei in Inverse Kinematics (SONIK) scattering chamber: a windowless, extended gas target surrounded by an array of 30 collimated silicon charged particle detectors situated at TRIUMF. This is the first elastic scattering measurement of 3He+4He made below 500 keV and it has greater angular range and better precision than previous measurements. The elastic scattering data were analyzed using both R-matrix and Halo Effective Field Theory (Halo EFT) frameworks, and values of the s-wave scattering length and effective range were extracted. The resulting improvement in knowledge of the s-wave effective-range function at low energies will reduce the overall uncertainty in S34 at solar energies.
