相关论文: Ammonia observations of bright-rimmed clouds: esta…

At a distance of 2.4kpc, W33 is an outstanding massive and luminous 10pc sized star forming complex containing quiescent infrared dark clouds as well as highly active infrared bright cloud cores heated by young massive stars. We report…

We present initial results from the K-band focal plane array Examinations of Young STellar Object Natal Environments (KEYSTONE) survey, a large project on the 100-m Green Bank Telescope mapping ammonia emission across eleven giant molecular…

We present ammonia observations of 193 dense cores and core candidates in the Perseus molecular cloud made using the Robert F. Byrd Green Bank Telescope. We simultaneously observed the NH3(1,1), NH3(2,2), CCS (2_1 -> 1_0) and CC34S (2_1 ->…

The dusty winds of cool evolved stars are a major contributor of the newly synthesised material enriching the Galaxy and future generations of stars. However, the details of the physics and chemistry behind dust formation and wind launching…

We mapped the MSX dark cloud G084.81-01.09 in the NH3 (1,1) - (4,4) lines and in the J = 1-0 transitions of 12CO, 13CO, C18O and HCO+ in order to study the physical properties of infrared dark clouds, and to better understand the initial…

[abridged] We present interferometric maps of ammonia (NH3) of the nearby starburst galaxy NGC 253 [star formation rate: ~2.8 Mo yr^(-1)]. The observations have been taken with the Australia Telescope Compact Array and include the para-NH3…

To constrain theoretical models of high-mass star formation, observational signatures of mass accretion in O-type forming stars are desirable. Using the JVLA, we have mapped the hot and dense molecular gas in the hot core NGC7538 IRS1, with…

We present Very Large Array observations of ammonia (NH3) (1,1), (2,2), and CCS (2_1-1_0) emission toward the Infrared Dark Cloud (IRDC) G19.30+0.07 at ~22GHz. The NH3 emission closely follows the 8 micron extinction. The NH3 (1,1) and…

The circumstellar ammonia (NH$_3$) chemistry in evolved stars is poorly understood. Previous observations and modelling showed that NH$_3$ abundance in oxygen-rich stars is several orders of magnitude above that predicted by equilibrium…

Observations of bright and variable "reflected" X-ray emission from molecular clouds located within inner hundred parsec of our Galaxy have demonstrated that the central supermassive black hole, Sgr A*, experienced short and powerful flares…

Observing inversion lines of ammonia (NH3), complemented by rotational lines of NH3 and other molecular species, provides stringent constraints on potential variations of the proton-to-electron mass ratio. While a limit of one part per…

We have carried out a radio-wavelength imaging survey of 45 bright-rimmed clouds (BRCs), using the Australia Telescope Compact Array to characterise the physical properties in their ionised boundary layers. We detected radio emission from a…

We use spectra and maps of NH2D, ND2H, and ND3, obtained with the CSO, IRAM 30m and Arecibo telescopes, to study deuteration processes in dense cores. The data include the first detection of the hyperfine structure of ND2H. The emission of…

Dense cores in massive, parsec-scale molecular clumps are sites that harbor protocluster formation. We present results from observations towards a hub-filament structure of a massive Infrared Dark Cloud (IRDC) G14.225-0.506 using the…

Spectral lines of ammonia, NH$_3$, are useful probes of the physical conditions in dense molecular cloud cores. In addition to advantages in spectroscopy, ammonia has also been suggested to be resistant to freezing onto grain surfaces,…

(abridged) We present ATCA and GBT observations of ammonia (NH3) toward the ultraluminous infrared galaxy (ULIRG) merger Arp220. We detect the NH3 (1,1), (2,2), (3,3), (4,4), (5,5), and (6,6) inversion lines in absorption against the…

Cha-MMS1 was mapped in the NH_3(1,1) line and the 1.2 cm continuum using the Australia Telescope Compact Array, ATCA. The angular resolution of the ATCA observations is 7'' (~ 1000 AU), and the velocity resolution is 50 m s^{-1}. The core…

We survey 44 young stellar objects located near the edges of mid-IR-identified bubbles in CS (1-0) using the Green Bank Telescope. We detect emission in 18 sources, indicating young protostars that are good candidates for being triggered by…

Obscured AGN represent a significant fraction of the entire AGN population, especially at high redshift (~70% at z=3--5). They are often characterized by the presence of large gas and dust reservoirs that are thought to sustain and possibly…

We have used the JVLA at the 1 cm band to map five highly-excited metastable inversion transitions of ammonia, (J,K)=(6,6), (7,7), (9,9), (10,10), and (13,13), in W51 IRS2 with ~0.2 angular resolution. We present detections of both thermal…