Feasibility study of online tuning of the luminosity in a circular collider with the robust conjugate direction search method

TL;DR

This paper investigates the use of the robust conjugate direction search (RCDS) method for online luminosity tuning in a circular collider, demonstrating its effectiveness through simulation and preliminary experiments.

Contribution

It demonstrates the feasibility of applying RCDS for online luminosity optimization in a collider, specifically using BEPCII as a case study.

Findings

RCDS can recover luminosity decreased by beam offset deviations

The method shows high noise tolerance in beam experiments

Preliminary online experiments support simulation results

Abstract

The robust conjugate direction search (RCDS) method has high tolerance to noise in beam experiments. It has been demonstrated that this method can be used to optimize the machine performance of a light source online. In our study, taking BEPCII as an example, the feasibility of online tuning of the luminosity in a circular collider is explored, through numerical simulation and preliminary online experiments. It is shown that the luminosity that is artificially decreased by a deviation of beam orbital offset from optimal trajectory can be recovered with this method.