One-loop matching for quark dipole operators in a gradient-flow scheme
One-loop matching for quark dipole operators in a gradient-flow scheme
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DOI：
10.1007/jhep04(2022)050
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发表时间：
2021-11
影响因子：
5.4
通讯作者：
E. Mereghetti;C. Monahan;Matthew D. Rizik;A. Shindler;P. Stoffer
中科院分区：
文献类型：
--
作者：
E. Mereghetti;C. Monahan;Matthew D. Rizik;A. Shindler;P. Stoffer
夸克色电偶极子(QCEDM)算符是一种违反CP的算符，它描述了在强子能量下，具有非零自旋的粒子对电偶极矩的超标准模型贡献。本文利用梯度流定义了非正则化格式中的重整化偶极子算符，并在微扰理论的一圈处对更常见的MS格式中的同维和低维的重整化算符进行了匹配。我们还确定了夸克色磁偶极子算符(QCMDM)的匹配系数，例如，它对与CP破坏和CP守恒Kaon衰变有关的矩阵元素有贡献。这一计算结果为以后对qCEDM和qCMDM算符的强子矩阵元进行晶格QCD计算提供了基础。
The quark chromoelectric dipole (qCEDM) operator is a CP-violating operator describing, at hadronic energies, beyond-the-standard-model contributions to the electric dipole moment of particles with nonzero spin. In this paper we define renormalized dipole operators in a regularization-independent scheme using the gradient flow, and we perform the matching at one loop in perturbation theory to renormalized operators of the same and lower dimension in the more familiar MS scheme. We also determine the matching coefficients for the quark chromo-magnetic dipole operator (qCMDM), which contributes for example to matrix elements relevant to CP-violating and CP-conserving kaon decays. The calculation provides a basis for future lattice QCD computations of hadronic matrix elements of the qCEDM and qCMDM operators.