不稳定粒子的一种新的波函数重整化方案

A New Wave-Function Renormalization Prescription for Unstable Particles

依据近几年提出的极点(pole)质量重整化方案对不稳定粒子提出了一种新的波函数重整化方案-极点波函数重整化方案,该方案中不稳定粒子的波函数重整化常数通过其传播子的极点处的留数得到.通过计算不稳定粒子的自能辐射修正我们发现对不稳定粒子新的波函数重整化常数和目前的波函数重整化常数相差一个规范参数相关项,这使得两种方案计算出的包含不稳定粒子产生或湮灭的物理过程的物理振幅模方在两圈(及以上)阶相差一个规范参数相关项,哪种波函数重整化方案是正确的,有待进一步研究.

A new wave-function renormalization prescription for unstable particles is put forward in this paper, based on the recently proposed pole mass renormalization prescription. In the new wave-function renormalization prescription the wave-function renormalization constant （WRC） is defined as the residue of the propagator of the unstable particle at its pole. The calculations of the radiative corrections of unstable particle＇s self energies show that the new WRC are different from the present WRC by gauge parameter dependent terms. This will lead to a difference of the amplitude module square of the physical process containing unstable particle＇s creation or annihilation obtained by the two wave-function renormalization prescriptions. Therefore, it is urgent to investigate which renormalization prescription is correct.