报告题目:  A new method for ISR corrections in e+e- experiments

报告人: Sergei S. Gribanov，Budker Institute of Nuclear Physics

报告时间: 2021年9月8日下午3点

报告地点: 吉林大学中心校区物理楼302

报告摘要:

In this talk, we propose a new method for obtaining a Born cross section using visible cross section data. It is assumed that the final state radiation is taken into account in a visible cross section, while in a Born cross section this effect is omitted. Since the equation that connects Born and visible cross sections is an integral equation of the first kind, the problem of finding its numerical solution is ill-posed. Various regularization based approaches are often used to solve ill-posed problems, since direct methods usually do not lead to an acceptable result. This naive method is based on finding a numerical solution to the integral equation by reducing it to a system of linear equations. The naive method works well because the kernel of the integral operator is a rapidly decreasing function of the variable x. This property of the kernel leads to the fact that the condition number of the matrix of the system of linear equations is of the order of unity, which makes it possible to neglect the ill-posedness of the problem when the above condition is satisfied. The advantages of the naive method are its model independence and the possibility of obtaining the covariance matrix of a Born cross section in a simple way.

举办单位：太阳集团电子游戏

　　　　　吉林大学理论物理中心