CH$_3$OH SUB-DOPPLER SPECTROSCOPY
MetadataShow full item record
Publisher:Ohio State University
The methanol torsion-rotation spectrum in the first three torsional states has been measured and analysed for a search of $m_e/m_p$ variations from comparison of radio astronomical and laboratory frequencies and for studies of systematic velocity motions in star-forming regions. The investigation is based on Lamb-dip measurements with sub-Doppler spectrometer developed at IAP RAS. CH$_3$OH-A and -E frequencies have been obtained with an accuracy of $\sim$1 kHz at 48$-$510~GHz for more than 500 transitions in $v_t=0$, more than 200 transitions in $v_t=1$ and 100 transitions in $v_t=2$. For many b-type transitions the removed degeneracy of the CH$_3$OH levels due to different nuclear spin statistics was measured in a form of doublets with unresolved hf structure. Some a-type transitions show resolved spin-rotational splitting.
Author Institution: Institute of Applied Physics of RAS, 46 Ulyanov str., 603950 Nizhny Novgorod, Russia