重夸克有效场论下重子矩阵元的1/mQ展开及Λ_b->Λ_cl_v<sup style="margin-left:-6px;">-</sup>衰变

1/mQ Expansion for Heavy Baryons and Λ_b->Λ_cl_v<sup style="margin-left:-6px;">-</sup>Transition in HQEFT

本文在重夸克有效场论框架下讨论了含有一个重夸克的重子间跃迁矩阵元的重夸克展开。该有效场论来自对完整QCD重夸克场的分解,其特点是有效拉氏密度中包括了正、反重夸克耦合项。本文将重子间跃迁矩阵元展开讨论到了阶,定义与重夸克自旋、味无关的波函数,得到形状因子、重子质量用这些波函数表示的1/mQ展开式。利用这些结果,文中从重子质量估计波函数的零反冲点值,并讨论了的衰变分支比。

The transition matrix elements between heavy baryons each of which contains a single heavy quark are stud-ied in the framework of heavy quark effective field theory. The framework is derived from the full QCD and the heavy quark-antiquark coupling effects are manifestly included in the effective Lagrangian. The transition matrix elements between heavy baryons are expanded up to order . A set of heavy quark spin-flavor independent wave functions are defined to describe these transitions. The form factors and baryon masses are then related to these wave functions. Based on the 1/mQ expansion, we discuss the semileptonic branching fraction of .