Silica Raman scattering probe for absolute calibration of Thomson scattering spectrometers

TL;DR

This paper introduces a silica Raman scattering probe for absolute calibration of Thomson scattering spectrometers, enabling rapid and accurate calibration in plasma physics experiments where conventional methods are insufficient.

Contribution

A novel solid state silica Raman scattering probe for absolute calibration of Thomson scattering systems in plasma physics.

Findings

Raman scattering off silica enables precise calibration.

The method works over a temperature range of 299-498 K.

Calibration accuracy surpasses conventional techniques.

Abstract

We have developed a solid state probe for an absolute irradiance calibration of the Thomson scattering system on the Large Plasma Device (LAPD), based on Raman scattering off silica. Measurements performed with a triple-grating spectrometer have investigated the intensities of a pulsed laser beam Raman scattered off crystalline and amorphous silica over a range of temperatures of relevance to the LAPD (299 - 498 K). The data were compared with Rayleigh and Raman scattering intensities in gaseous nitrogen. The measurements show that Raman scattering off quartz allows rapid and accurate alignment and calibration of Thomson scattering systems in plasma physics experiments that cannot be calibrated using conventional methods.