相关论文: Deuterated methanol toward NGC 7538-IRS1
Using the Haystack Observatory 37-m radio telescope we have undertaken a search for emission in the 2(0)-3(1)E rotational transition of methanol in its first torsionally excited state (v_t=1) at 44.9 GHz. We examined seven galactic sources…
Class I methanol masers are collisionally pumped and are generally correlated with outflows in star forming sites in the Galaxy. Using the VLA in its A-array configuration, we present a spectral line survey to identify methanol…
The high abundances of Complex Organic Molecules (COMs) with respect to methanol, the most abundant COM, detected towards low-mass protostars, tend to be underpredicted by astrochemical models. This discrepancy might come from the large…
We present the results of a survey of a small sample (14) of low-mass protostars (L_IR < 10^3 Lsun) for 6.7 GHz methanol maser emission performed using the ATNF Parkes radio telescope. No new masers were discovered. We find that the lower…
We present an interferometric survey of the 44 GHz class I methanol maser transition toward a sample of 69 sources consisting of High Mass Protostellar Object candidates and Ultracompact (UC) H II regions. We found a 38% detection rate (16…
An ever growing number of observational and theoretical evidence suggests that the deuterated fraction (column density ratio between a species containing D and its hydrogenated counterpart, Dfrac) is an evolutionary indicator both in the…
We observed 14 methanol transitions near lambda=2 mm in Galactic star-forming regions. Broad, quasi-thermal J(0)-J(-1)E methanol lines near 157 GHz were detected toward 73 sources. Together with the 6(-1)-5(0)E and 5(-2)-6(-1)E lines at 133…
Six young bipolar outflows in regions of low-to-intermediate-mass star formation were observed in the 7_0-6_1A+, 8_0-7_1A+, and 5_{-1}-4_0E methanol lines at 44, 95, and 84 GHz, respectively. Narrow features were detected towards NGC…
We report the discovery of a widespread population of collisionally excited methanol J = 4_{-1} to 3$_0 E sources at 36.2 GHz from the inner 66'x18' (160x43 pc) of the Galactic center. This spectral feature was imaged with a spectral…
Interstellar objects are interlopers from other planetary systems, and their volatile compositions provide a glimpse into planet formation around their host star. We present near-infrared spectra of the coma of interstellar object 3I/ATLAS…
The recent detection of gas-phase methanol (CH$_3$OH) lines in the disc of TW Hya by Walsh et al. provided the first observational constraints on the complex O-bearing organic content in protoplanetary discs. The emission has a ring-like…
Among the tracers of the earliest phases in the massive star formation process, methanol masers have gained increasing importance. The phenomenological distinction between Class I and II methanol masers is based on their spatial association…
We present results of the investigations of the properties of the methanol $J_1 - J_0$ A$^{-+}$ line series motivated by the recent serendipitous detection of the maser emission in the $14_1 - 14_0$ A$^{-+}$ line at 349~GHz in S255IR-SMA1…
Context: Methanol masers of Class I (collisionally-pumped) and Class II (radiatively-pumped) have been studied in great detail in our Galaxy in a variety of astrophysical environments such as shocks and star-forming regions and are helpful…
The destiny of complex organic molecules (COMs) in star-forming regions is interlinked with various evolutionary phases. Therefore, identifying these species in diversified environments of identical star-forming regions would help to…
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…
We report an extensive rotational spectroscopic analysis of singly deuterated methyl mercaptan (CH$_{2}$DSH) using both millimeter and far-infrared synchrotron spectra to achieve a global torsional analysis of the three lowest torsional…
Gravitational collapse is one of the most important processes in high-mass star formation. Compared with the classic blue-skewed profiles, redshifted absorption against continuum emission is a more reliable method to detect inward motions…
We report on a large 44 GHz ($7_0-6_1$ A$^+$) methanol (CH$_3$OH) maser survey of the Galactic Center (GC). The Karl G. Jansky Very Large Array was used to search for CH$_3$OH maser emission covering a large fraction of the region around…
We have used the ATNF Mopra antenna and the SEST antenna to search in the directions of several class II methanol maser sources for emission from six methanol transitions in the frequency range 85-115 GHz. The transitions were selected from…