Absolute Frequency Atlas from 915 nm to 985 nm based on Laser Absorption Spectroscopy of Iodine

TL;DR

This paper presents a comprehensive iodine absorption atlas from 915 nm to 985 nm with nearly 10,000 reference lines, aiding laser calibration and refining molecular models.

Contribution

It provides a high-precision iodine spectral atlas over a broad wavelength range using a calibrated tunable diode laser, with an uncertainty of 50 MHz.

Findings

Almost 10,000 reference lines identified

Good agreement with previous spectral data

Dataset enables refinement of iodine molecular models

Abstract

This article reports on laser absorption spectroscopy of iodine gas between 915 nm and 985 nm. This wavelength range is scanned utilizing a narrow linewidth and mode-hop-free tunable diode-laser whose frequency is actively controlled using a calibrated wavelength meter. This allows us to provide an iodine atlas that contains almost 10,000 experimentally observed reference lines with an uncertainty of 50 MHz. For common lines, good agreement is found with a publication by Gerstenkorn et al. [S. Gerstenkorn, P. Luc, Atlas du spectre d'absorption de la molecule d'iode 14800-20000 cm$^{-1}$, Paris: Editions du Centre National de la Recherche Scientifique (CNRS), 1978]. The new rich dataset allows existing models of the iodine molecule to be refined and can serve as a reference for laser frequency calibration and stabilization.