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We report the detection of the Zeeman effect in the 44 GHz Class I methanol maser line toward the star forming region DR21(OH). In a 219 Jy/beam maser centered at an LSR velocity of 0.83 km s$^{-1}$, we find a 20-$sigma$ detection of $zB_{text{los}} = 53.5 pm 2.7$ Hz. If 44 GHz methanol masers are excited at $n sim 10^{7-8}$ cm$^{-3}$, then the $B~vs.~n^{1/2}$ relation would imply from comparison with Zeeman effect detections in the CN($1-0$) line toward DR21(OH) that magnetic fields traced by 44 GHz methanol masers in DR21(OH) should be $sim$10 mG. Together with our detected $zB_{text{los}} = 53.5$ Hz, this would imply that the value of the 44 GHz methanol Zeeman splitting factor $z$ is $sim$5 Hz mG$^{-1}$. Such small values of $z$ would not be a surprise, as the methanol molecule is non paramagnetic, like H$_2$O. Empirical attempts to determine $z$, as demonstrated, are important because currently there are no laboratory measurements or theoretically calculated values of $z$ for the 44 GHz methanol transition. Data from observations of a larger number of sources are needed to make such empirical determinations robust.
We report the detection of the Zeeman effect in the 44 GHz Class I methanol maser line toward the high mass star forming region DR21W. There are two prominent maser spots in DR21W at the ends of a northwest-southeast linear arrangement. For the maser
We present a second epoch of observations of the 44 GHz Class I methanol maser line toward the star forming region OMC-2. The observations were carried out with the Very Large Array, and constitute one of the first successful Zeeman effect detections
We have used the Australia Telescope Compact Array (ATCA) to search for emission from the $4_{-1} rightarrow 3_{0}E$ transition of methanol (36.2 GHz) towards the center of the nearby starburst galaxy NGC253. Two regions of emission were detected, of
We present a (sub)millimeter line survey of the methanol maser outflow located in the massive star-forming region DR21(OH) carried out with the Submillimeter Array (SMA) at 217/227 GHz and 337/347 GHz. We find transitions from several molecules towar
We report the results of a search for class II methanol masers at 37.7, 38.3 and 38.5 GHz towards a sample of 70 high-mass star formation regions. We primarily searched towards regions known to show emission either from the 107 GHz class II methanol