Files in this item

FilesDescriptionFormat

application/vnd.openxmlformats-officedocument.presentationml.presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation1088155.pptx (9MB)
PresentationMicrosoft PowerPoint 2007

application/pdf

application/pdf2965.pdf (20kB)
AbstractPDF

Description

Title:SUB-DOPPLER SPECTROSCOPY OF THE ν3 BAND OF METHANE
Author(s):Kocheril, Philip A.
Contributor(s):McCall, Benjamin J.; Dieter, Thomas S; Schrader, Alex W; Esposito, Anne Marie; Markus, Charles R.
Subject(s):Linelists, Lineshapes, Collisions
Abstract:Methane has been observed in brown dwarfs\footnote{B. Oppenheimer, S. Kulkarni, K. Matthews \textit{et al.}, \textit{Astrophys. J.} (1998), \textbf{502(2)}, 932-943.} and planetary atmospheres, including planets in our solar system\footnote{T. Owen, R. Cess, \textit{Astrophys. J.} (1975), \textbf{197}, L37-L40.} and extrasolar planets.\footnote{M. Swain, G. Vasisht, G Tinetti \textit{et al.}, \textit{Nature} (2008), \textbf{452}, 329-331.} Methane is also a potent greenhouse gas\footnote{M. Khalil, \textit{Annu. Rev. Energy Environ.} (1999), \textbf{24}, 645-661.} and relevant to ozone formation and depletion in Earth’s atmosphere.\footnote{O. Boucher, P. Friedlingstein, B. Collins \textit{et al.}, \textit{Environ. Res. Lett.} (2009), \textbf{4(4)}, 044007.} As the simplest stable hydrocarbon, methane is also a benchmark for state-of-the-art \textit{ab initio} calculations.\footnote{A. Nikitin, M. Rey, V. Tyuterev, \textit{J. Quant. Spectrosc. Radiat. Transf.} (2017), \textbf{200}, 90-99.} While methane is a strong absorber due to its characteristically large transition dipole moments, transition frequencies were historically limited by Doppler broadening, and many frequencies are still known only to Doppler-limited precision. We have constructed a double-pass saturation experiment to perform sub-Doppler spectroscopy of rovibrational transitions of methane. With the accuracy provided by optical frequency combs, we have measured 22 methane transitions from the $\nu_3$ band in the 3 $\mu$m region to MHz-level uncertainty, improving the accuracy of the rest frequencies by at least an order of magnitude. This data can be used for higher-precision models of methane as an \textit{ab initio} benchmark.
Issue Date:06/18/18
Publisher:International Symposium on Molecular Spectroscopy
Citation Info:APS
Genre:Conference Paper / Presentation
Type:Text
Language:English
URI:http://hdl.handle.net/2142/100798
DOI:10.15278/isms.2018.MI02
Other Identifier(s):MI02
Date Available in IDEALS:2018-08-17
2018-12-12


This item appears in the following Collection(s)

Item Statistics