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arXiv · 2407.01297

Millimeter-millimeter-wave double-modulation double-resonance spectroscopy

Oliver Zingsheim·Luis Bonah·Frank Lewen·Sven Thorwirth·Holger S. P. Müller·Stephan Schlemmer
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Abstract

A new millimeter- to millimeter-wave double-modulation double-resonance (MMW-MMW DM-DR) scheme has been applied to record spectra of two astronomically relevant complex organic molecules (COMs), propanal (C2H5CHO) and ethyl cyanide (C2H5CN), to demonstrate advantages of the DM-DR experimental technique. The DR technique helps to identify target transitions in a forest of lines and the implementation of a DM procedure (modulation of the pump and probe source) allows for confusion- and baseline-free spectra containing only the line(s) of interest. In particular the unambiguous assignment of weak and blended transitions in very dense MMW spectra is highlighted. Details of the observed Autler-Townes line splitting and possible future applications, such as automated analyses and adaptions of DM-DR methods to other experimental setups, are discussed.

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Oliver Zingsheim, Luis Bonah, Frank Lewen, Sven Thorwirth, Holger S. P. Müller, Stephan Schlemmer. 2024-07-01. Millimeter-millimeter-wave double-modulation double-resonance spectroscopy. https://doi.org/10.1016/j.jms.2021.111519

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