Department of Physics, University of Pisa, 56127 Pisa, Italy and INFN-Pisa, 56127 Pisa, Italy.
Phys Rev Lett. 2012 Feb 3;108(5):052502. doi: 10.1103/PhysRevLett.108.052502. Epub 2012 Jan 31.
The muon-capture reactions {2}H(μ{-},ν{μ})nn and {3}He(μ{-},ν{μ}){3}H are studied with nuclear potentials and charge-changing weak currents, derived in chiral effective field theory. The low-energy constants (LECs) c{D} and c{E}, present in the three-nucleon potential and (c{D}) axial-vector current, are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The muon-capture rates on deuteron and {3}He are predicted to be 399±3 sec{-1} and 1494±21 sec{-1}, respectively. The spread accounts for the cutoff sensitivity, as well as uncertainties in the LECs and electroweak radiative corrections. By comparing the calculated and precisely measured rates on {3}He, a value for the induced pseudoscalar form factor is obtained in good agreement with the chiral perturbation theory prediction.
μ 捕获反应 {2}H(μ{-},ν{μ})nn 和 {3}He(μ{-},ν{μ}){3}H 用核势和电荷变化弱电流进行研究，这些势和电流是在手征有效场论中导出的。在三体势和（c{D}）轴矢流中存在的低能常数 c{D} 和 c{E}，被约束以重现 A=3 的束缚能和氚的伽莫夫-泰勒矩阵元。预测的氘和 {3}He 的 μ 捕获率分别为 399±3 sec{-1}和 1494±21 sec{-1}。这种分布考虑了截止敏感性，以及低能常数和电弱辐射修正的不确定性。通过比较计算和精确测量的 {3}He 速率，得到了与手征微扰理论预测相符的诱导赝标量形状因子值。
