We present a high-accuracy calculation of the deuteron structure radius in chiral effective field theory. Our analysis employs the state-of-the-art semilocal two-nucleon potentials and takes into account two-body contributions to the charge density operators up to fifth order in the chiral expansion. The strength of the fifth-order short-range two-body contribution to the charge density operator is adjusted to the experimental data on the deuteron charge form factor. A detailed error analysis is performed by propagating the statistical uncertainties of the low-energy constants entering the two-nucleon potentials and by estimating errors from the truncation of the chiral expansion as well as from uncertainties in the nucleon form factors. Using the predicted value for the deuteron structure radius together with the very accurate atomic data for the difference of the deuteron and proton charge radii we, for the first time, extract the charge radius of the neutron from light nuclei. The extracted value reads $r_n^2 = - 0.106 \substack{ +0.007\\ -0.005\\} \, \text{fm}^2$ and its magnitude is about $1.7σ$ smaller than the current value given by the Particle Data Group. In addition, given the high accuracy of the calculated deuteron charge form factor and its careful and systematic error analysis, our results open the way for an accurate determination of the nucleon form factors from elastic electron-deuteron scattering data measured at the Mainz Microtron and other experimental facilities.
Lowest-order QED radiative corrections in unpolarized elastic electron-deuteron scattering beyond the ultra-relativistic limit for the proposed deuteron charge radius measurement at Jefferson Laboratory
K0 photoproduction on the deuteron and the extraction of the elementary amplitude
研究了氘核上光生K_0的过程,包括YN和KN终态相互作用(FSI),以及π介子介导的γ d --> pi NN --> KYN过程。在阈值区,内含截面的YN再散射效应较大。极化观测值在较大的K介子和超子角下显示出相当大的FSI效应。结果表明,在FSI效应可以忽略的准自由散射区,提取基元γ N -> KY振幅是可能的。此外,在该区域中的截面是大的,表明在该运动学区域中的测量是有利的。
On the Extraction of Cross Sections for pi0 and eta Photoproduction off Neutrons from Deuteron Data
本文讨论了从氘核数据中提取中性赝标介子离中子光生截面的过程。主要的陈述是,质子和中子靶的末态相互作用(FSI)修正通常是不相等的,但对于π 0的产生,有一些特殊情况,它们必须是相同的,并且在入射光子能量和π极角θ^* 的参数空间中有很大的区域,它们碰巧非常相似。由于这种激发的特定的同位旋结构,在Delta(1232)3/2+共振的能量范围内,对于$π_0$的产生,对两个靶核子的校正实际上是相同的。同样在$Δ$ -等压线范围以上,质子和中子修正因子之间的大差异仅在极端前向角($θ^*$ < 20度)下预测,但结果在较大角下相似。讨论了gp-> pi 0 p和gn-> pi 0 n修正因子的数值结果。并给出了gd--> pi 0 pn截面的模型描述。
在μ氘的$μ^- p n$系统的几个身体形式主义内的领先顺序($α^4$)有限尺寸修正进行评估,并发现是敏感的输入的氘核波函数。我们表明,这种灵敏度,连同精确的氘核电荷半径确定的μ原子光谱可以用来确定难以捉摸的氘核D-状态的概率,$P_D$,对于一个给定的模型的核子核子(NN)的潜力。在手性NN模型中用$P_D$计算的半径为4.3%,在高精度NN势中用$P_D$计算的半径约为5.7%,最受$μ^-d$数据的青睐。
Unitarity constraint for threshold coherent pion photoproduction on the deuteron and chiral perturbation theory
利用么正性约束计算了两步过程gamma + d -> p + n -> pi 0 + d对氘核相干π介子产生振幅虚部的贡献。结果表明,这种吸收过程是不可忽略的,在从阈区γ + d -> pi 0 + d截面中提取基元中子产生幅度时,必须考虑这种吸收过程。此外,还指出在次主导阶以上的重子手征微扰理论中,gamma + d -> pi 0 + d的一致计算需要包含这个吸收过程.
Two-Nucleon Systems in a Finite Volume: (II) 3S1-3D1 Coupled Channels and the Deuteron
立方体积中两个核子的能谱提供了两个相移和一个混合角的途径,它们定义了包含氘核的3S 1 - 3D 1耦合通道中的S矩阵。借助最近导出的能量量子化条件,这样的系统,和已知的散射参数,这些光谱预测的体积范围。结果表明,在体积为10 fm <~ L <~ 14 fm的情况下,用格点量子色动力学计算|P| <= 2 pi sqrt{3}/L的双核子系统,可以提取无限体积的氘核结合能和主要散射参数,包括氘核极点处的S-D混合角.讨论了从格点量子色动力学计算中提取氘子波函数渐近D/S比的可行性。
Robust extraction of proton charge radius from electron-proton scattering data
Extracting the proton charge radius from electron scattering data requires determining the slope of the charge form factor at $Q^2$ of zero. But as experimental data never reach that limit, numerous methods for making the extraction have been proposed, though often the functions are determined after seeing the data which can lead to confirmation bias. To find functional forms that will allow for a robust extraction of the input radius for a wide variety of functional forms in order to have confidence in the extraction from upcoming low $Q^2$ experimental data such as the Jefferson Lab PRad exp…
First Extraction of the Matter Radius of $^{132}$Sn via Proton Elastic Scattering at 200 MeV/Nucleon
RIKEN Nishina Center for Accelerator-Based Science(理化学研究所仁科加速器科学中心);Department of Physics, Kyoto University(京都大学物理学系);RIKEN Cluster for Pioneering Research(理化学研究所先锋研究集群);Institute of Modern Physics, Chinese Academy of Sciences(中国科学院近代物理研究所);Research Center for Nuclear Physics, University of Osaka(大阪大学核物理研究中心);Department of Physics, Konan University(神户女学院大学物理学系);Research Center for Accelerator and Radioisotope Science, Tohoku University(东北大学加速器与放射性同位素科学研究);Université Paris-Saclay, CNRS/IN2P3, IJCLab(巴黎萨克雷大学,法国国家科学研究中心/法国原子能和替代能源委员会,IJCLab);Technische Universität Darmstadt, Department of Physics(达姆施塔特工业大学物理学系);ExtreMe Matter Institute EMMI and Helmholtz Forschungsakademie Hessen für FAIR (HFHF), GSI Helmholtzzentrum für Schwerionenforschung GmbH(极端物质研究所EMMI和黑森FAIR赫尔霍兹研究院(HFHF),GSI重离子研究中心有限公司);Center for Computational Sciences, University of Tsukuba(筑波大学计算科学中心);Center for Nuclear Study, the University of Tokyo(东京大学核研究分中心);Department of Physics, Kyungpook National University(庆北国立大学物理学系);Department of Physics, Toho University(东海大学物理学系);Department of Applied Physics, University of Fukui(福井大学应用物理学系);Department of Physics, University of Osaka(大阪大学物理学系);HUN-REN Institute for Nuclear Research (HUN-REN ATOMKI)(匈牙利研究与创新网络核物理研究所(HUN-REN ATOMKI));Department of Physics, The University of Hong Kong(香港大学物理学系);Faculty of Engineering, University of Miyazaki(宫崎大学工学部)
Rescattering effects in antiproton-induced exclusive $J/ψ$ and $ψ^\prime$ production on the deuteron
在广义程函近似的基础上,研究了游离质子靶上粲偶素生成阈值附近的排他反应$\bar p d \to J/ψ\, n$和$\bar p d \to ψ^\prime\, n$。结果表明,传入的反质子和传出的charmonium的旁观者中子上的再散射导致消耗的charmonium生产在低-和增强在高横动量。这是在定性协议与以前的研究硬质子敲除质子-氘核碰撞。我们分析了不同的物理来源的不确定性,这可能会影响提取的总粲中子截面。入射$\bar p$的色透明效应在很大程度上补偿了粲偶素在低和高横动量下的再散射影响。不同的氘核波函数的选择导致在高横动量显着的不确定性。作为粲偶素产生计算的结果,我们还提供了由于粲偶素在中子上解离而产生开粲强子的预测。结果表明,开粲产生截面与总粲-核子截面成正比,且相对于模型其它参数的变化相当稳定。因此,我们建议开放的魅力通道是最适合在PANDA与氘靶的粲-核子相互作用的未来研究。
Comment on "Nuclear structure corrections in muonic deuterium"
最近的一封信[1]研究了μ D原子中氘核极化率的影响。了解这个原子的重要性已经提高,因为它可能会对质子半径之谜有所启发。在这里,我们确认,澄清,并强调的结果[1]的意义,第三泽马赫矩的影响被部分的氘核极化率效应抵消。1. K. Pachucki,Phys. Rev. Lett. 106、193007(2011)