Self-broadening and self-shift in the $\mathbf{3\nu_{2}}$ band of ammonia from mid-infrared-frequency-comb spectroscopy

TL;DR

This study presents high-precision broadband absorption spectra of ammonia's 3ν₂ band using mid-infrared frequency comb spectroscopy, providing detailed line parameters and demonstrating improved accuracy over existing databases.

Contribution

The paper introduces a novel broadband spectroscopic method with high resolution for ammonia, yielding precise line parameters and validating against HITRAN 2016.

Findings

Good agreement with HITRAN 2016 data

Enhanced precision in line position and shift measurements

Rapid tunability enables advanced molecular gas spectroscopy

Abstract

We report the broadband absorption spectrum of the $3\nu_{2}$ band of $^{14}$NH$_{3}$ near 4 $\mu m$. The data were recorded using a mid-infrared frequency comb coupled to a homebuilt Fourier-transform spectrometer with a resolution of 0.00501 $cm^{-1}$. Line positions, line intensities, self-broadening, and self-shift parameters for six rovibrational lines were determined at room temperature ($T=296$ K). Comparison with HITRAN 2016 shows good agreement at improved precision. The high precision and the rapid tunability of our experiment enables advanced fast spectroscopy of molecular gases.