相关论文: An Extensive, Sensitive Search for SiO Masers in H…
We present results on a search for 86.243 GHz SiO (J = 2 -- 1, v = 1) maser emission toward 67 OH/IR stars located near the Galactic Centre. We detected 32 spectral peaks, of which 28 correspond to SiO maser lines arising from the envelopes…
We present the first images of the 28SiO v=1, J=2-1 maser emission around the closest known massive young stellar object Orion Source I observed at 86 GHz (3mm) with the VLBA. These images have high spatial (~0.3 mas) and spectral (~0.054…
We present new observations of C-band continuum emission and masers to assess high-mass ($>$8 $M_\odot$) star formation at early evolutionary phases in the inner 200 pc of the Central Molecular Zone (CMZ) of the Galaxy. The continuum…
W51-IRS2 is known to be one of the most prolific sources of interstellar ammonia (NH$_3$) maser lines. So far, however, many of these inversion lines have rarely been studied. Here we report spectrally resolved line profiles for the…
Maser emission of SiO, H$_2$O and, OH is widespread in Asymptotic Giant Branch (AGB) stars with oxygen(O)-rich envelopes. This emission quickly disappear during the post-AGB phase and is extremely rare in planetary nebulae (PN). So far,…
We present high-resolution images of the submillimeter SiO line emissions of a massive young stellar object Orion Source I using the Atacama Large Millimeter/ Submillimeter Array (ALMA) at band 8. We detected the 464 GHz SiO v=4 J=11-10…
The production of silicon monoxide (SiO) can be considered as a fingerprint of shock interaction. In this work, we use high-sensitivity observations of the SiO (2-1) and H$^{13}$CO$^{+}$ (1-0) emission to investigate the broad and narrow…
We present data of proper motions of OH masers in the massive star-forming regions ON 1, K3-50, and W51 Main/South. OH maser motions in ON 1 are consistent with expansion at approximately 5 km/s, likely tracing the expanding ultracompact H…
We present high-resolution Karl G. Jansky Very Large Array observations of the 22 GHz $\mathrm{H_2O}$ maser line in the extended Sagittarius B2 cloud. We detect 499 $\mathrm{H_2O}$ masers across the observed velocities between -39 and 172…
We present a study of the Silicon-bearing species detected in a line confusion limited survey towards Orion KL performed with the IRAM 30-m telescope, which ranges from 80 to 280 GHz. Our aim is to derive physical and chemical conditions…
Using Science Verification data from the Atacama Large Millimeter/Submillimeter Array (ALMA), we have identified and imaged five rotational transitions (J=5-4 and J=6-5) of the three silicon monoxide isotopologues 28SiO v=0, 1, 2 and 29SiO…
We report the results of mapping observations of the bipolar nebula with SiO maser emission, IRAS 19312+1950, in the CO (J=1-0 and J=2-1), 13CO (J=1-0 and J=2-1), C18O (J=1-0), CS (J=2-1), SO (J_K=3_2-2_1) and HCO+ (J=3-2) lines with the…
Mapping and monitoring observations of SiO maser sources near the Galactic center were made with the Nobeyama 45-m telescope at 43 GHz. Rectangular mapping an area of approximately 200'' x 100''$ in a 30'' grid, and triangular mapping in a…
With the 100-m telescope at Effelsberg, 19 ammonia (NH3) maser lines have been detected toward the prominent massive star forming region W51-IRS2. Eleven of these inversion lines, the (J,K) = (6,2), (5,3), (7,4), (8,5), (7,6), (7,7), (9,7),…
We present high angular resolution ($\sim$ 3$''$) and sensitive 1.3 mm continuum, cyanogen (CN) and vinyl cyanide (C$_2$H$_3$CN) line observations made with the Submillimeter Array (SMA) toward one of most highly obscured objects of the W51…
We present mid-infrared (MIR) observations, made with the TIMMI2 camera on the ESO 3.6 m telescope, toward 14 young massive star-forming regions. All regions were imaged in the N band, and nine in the Q band, with an angular resolution of ~…
Theoretical models suggest that massive stars form via disk-mediated accretion, with bipolar outflows playing a fundamental role. A recent study toward massive molecular outflows has revealed a decrease of the SiO line intensity as the…
We have discovered a new H$_2$CO (formaldehyde) $1_{1,0}-1_{1,1}$ 4.82966 GHz maser in Galactic Center Cloud C, G0.38+0.04. At the time of acceptance, this is the eighth region containing an H$_2$CO maser detected in the Galaxy. Cloud C is…
Aims.Molecular masers, including methanol and hydroxyl masers, and in particular the ones in excited rotational states (ex-OHmasers), are one of the most informative tools for studying star-forming regions. So, the discovery, of new maser…
Recent observational and theoretical advances have called into question traditional OH maser pumping models in evolved (OH/IR) stars. The detection of excited-state OH lines would provide additional constraints to discriminate amongst these…