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arXiv · 1302.7245

Prospects for high-resolution microwave spectroscopy of methanol in a Stark-deflected molecular beam

Paul Jansen·Isabelle Kleiner·Congsen Meng·Ronald M. Lees·Maurice H. M. Janssen·Wim Ubachs·Hendrick L. Bethlem
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Abstract

Recently, the extremely sensitive torsion-rotation transitions in methanol have been used to set a tight constraint on a possible variation of the proton-to-electron mass ratio over cosmological time scales. In order to improve this constraint, laboratory data of increased accuracy will be required. Here, we explore the possibility for performing high-resolution spectroscopy on methanol in a Stark-deflected molecular beam. We have calculated the Stark shift of the lower rotational levels in the ground torsion-vibrational state of CH3OH and CD3OH molecules, and have used this to simulate trajectories through a typical molecular beam resonance setup. Furthermore, we have determined the efficiency of non-resonant multi-photon ionization of methanol molecules using a femtosecond laser pulse. The described setup is in principle suited to measure microwave transitions in CH3OH at an accuracy below 10^{-8}.

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Paul Jansen, Isabelle Kleiner, Congsen Meng, Ronald M. Lees, Maurice H. M. Janssen, Wim Ubachs, Hendrick L. Bethlem. 2013-02-28. Prospects for high-resolution microwave spectroscopy of methanol in a Stark-deflected molecular beam. https://doi.org/10.1080/00268976.2013.802819

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