A new method to suppress high-order harmonics for synchrotron radiation soft x-ray beamline

TL;DR

This paper proposes a practical method to reduce high-order harmonics in soft x-ray beamlines by adjusting the exit arm length, improving light purity for synchrotron radiation applications.

Contribution

It introduces a simple, effective technique to suppress higher harmonics in VLS plane grating monochromators, validated through calculations and experiments.

Findings

Decreasing the included angle improves light purity.

Method successfully applied in detector calibration experiments.

Significant reduction of high-order harmonics achieved.

Abstract

A feasible and convenient method has been proposed to suppress higher-harmonics for varied-line-spacing (VLS) plane grating monochromator in soft x-ray region. Related calculations and experiments demonstrate that decreasing the included angle slightly by changing the parameter of exit arm length can significantly improve light purity. This method is suitable and has been used for experiments of detector calibration in beamline 4B7B at Beijing Synchrotron Radiation Facility (BSRF).