Precision Spectroscopy of Nitrous Oxide Isotopocules with a Cross-Dispersed Spectrometer and Mid-Infrared Frequency Comb

Abstract

As a potent greenhouse gas and ozone depleting agent, nitrous oxide (N${}_2$O) plays a critical role in the global climate. Effective mitigation relies on understanding global sources and sinks which can be supported through isotopic analysis. We present a cross-dispersed spectrometer, coupled with a mid-infrared frequency comb, capable of simultaneously monitoring all singly substituted, stable isotopic variants of N${}_2$O. Rigorous evaluation of the instrument lineshape function and data treatment are discussed. Laboratory characterization of the spectrometer demonstrates sub-GHz spectral resolution and an average precision of $7.4\times 10^{-6}$ for fractional isotopic abundance retrievals in 1 s.

arXiv comment8 pages, 9 figures, 1 table, 40 references

References in corpus (5)

• Frequency comb spectroscopy
• Surpassing the Path-Limited Resolution of a Fourier Transform Spectrometer with Frequency Combs
• Direct Frequency Comb Measurement of OD + CO -> DOCO Kinetics
• Mid-infrared VIPA Spectrometer for Rapid and Broadband Trace Gas Detection
• Self-starting harmonic frequency comb generation in a quantum cascade laser

Cited by in corpus (3)

• Isotope Ratio Dual-Comb Spectrometer
• Precision frequency comb spectroscopy of the ${}^{14}$N${}_2$O, ${}^{14}$N${}^{15}$NO, ${}^{15}$N${}^{14}$NO, and ${}^{15}$N${}_2$O isotopocules in the 3300-3550 cm${}^{-1}$ range
• An air-spaced virtually imaged phased array with 94 MHz resolution for precision spectroscopy