相关论文: A Luminous Blue Variable Star Interacting with a N…
We explore the relationship between gas and dust in massive star-forming regions by comparing physical properties derived from each. We compare the temperatures and column densities in a massive star-forming Infrared Dark Cloud (IRDC,…
MWC 930 is a star just ~2{\deg} above the Galactic plane whose nature is not clear and that has not been studied in detail so far. While a post-Asymptotic Giant Branch (AGB) classification was proposed in the past, studies of its optical…
Context: GR290 (M33 V0532=Romano's star) is a luminous M33 object undergoing photometric variability typical for luminous blue variable (LBV) stars. It lies inside Wolf-Rayet region in the Hertzsprung-Russell diagram and possesses a WN8…
We performed spectroscopy of five Luminous Blue Variable (LBV) candidates and two known LBV stars (AE And and Var A-1) in M31. We obtained the same-epoch near-infrared (NIR) and optical spectra of these stars. The NIR spectra were taken…
We report the discovery of two new Galactic candidate luminous blue variable (cLBV) stars via detection of circular shells (typical of known confirmed and cLBVs) and follow-up spectroscopy of their central stars. The shells were detected at…
High-mass star forming regions are typically thought to be dominated by supersonic motions. We present combined Very Large Array and Green Bank Telescope (VLA+GBT) observations of NH$_3$ (1,1) and (2,2) in the infrared dark cloud (IRDC)…
High spatial and sensitivity images of the Luminous Blue Variable IRAS 18576+0341 were obtained using the mid infrared imager VISIR at the Very Large Telescope and the Very Large Array interferometer. The resulting mid-infrared continuum…
We have found three new LBV candidates in the star-forming galaxy NGC 4736. They show typical well-known LBV spectra, broad and strong hydrogen lines, He I lines, many Fe II lines, and forbidden [Fe II] and [Fe III]. Using archival Hubble…
We present new millimeter and infrared spectroscopic observations towards the radio nebula G10.0-0.3, which is powered by the wind of the Luminous Blue Variable star LBV 1806-20, also closely associated with the soft gamma-ray repeater SGR…
The iconic planetary nebula (PN) NGC 7027 is bright, nearby (D ~ 1 kpc), highly ionized, intricately structured, and well observed. This nebula is hence an ideal case study for understanding PN shaping and evolution processes. Accordingly,…
To unravel the star formation process, we present a multi-scale and multi-wavelength study of the filamentary infrared dark cloud (IRDC) G333.73+0.37, which hosts previously known two HII regions located at its center. Each HII region is…
We report on the discovery of a luminous blue variable (LBV) lying ~7 pc in projection from the Quintuplet cluster. This source, which we call LBV G0.120-0.048, was selected for spectroscopy owing to its detection as a strong source of…
We search for LBV stars in galaxies outside the Local Group. Here we present a study of two bright $H\alpha$ sources in the NGC 247 galaxy. Object j004703.27-204708.4 ($M_V=-9.08 \pm 0.15^m$) shows the spectral lines typical for…
We have carried out the NH$_3$ $(J,K)=(1,1),(2,2),$ and $(3,3)$ mapping observations toward the Galactic infrared bubble N49 (G28.83-0.25) using the Nobeyama 45 m telescope. Three NH$_3$ clumps (A, B, and C) were discovered along the…
Infrared-dark clouds (IRDCs) are believed to be the birthplaces of rich clusters and thus contain the earliest phases of high-mass star formation. We use the Green Bank Telescope (GBT) and Very Large Array (VLA) maps of ammonia (NH3) in six…
We present Very Large Array observations of NH3 (1,1) and (2,2) in a sample of six infrared-dark clouds (IRDCs) with distances from 2 to 5 kpc. We find that ammonia serves as an excellent tracer of dense gas in IRDCs, showing no evidence of…
Context. Luminous blue variables (LBVs) are rare massive stars with very high luminosity. They are characterized by strong photo-metric and spectroscopic variability related to transient eruptions. The mechanisms at the origin of these…
This study presents an investigation of nearly two dozen candidate Luminous Blue Variables (cLBVs) in the galaxies M31 and M33. Eight stars have been studied in detail, while an additional sixteen objects are briefly mentioned. Multi-epoch…
Infrared dark clouds (IRDCs) likely represent very early stages of high-mass star/star cluster formation. In this study, we aim to determine the physical properties and spatial distribution of dense clumps in the IRDC MSXDC G304.74+01.32…
How Supernova Remnant (SNR) shocks impact nearby molecular clouds is still poorly observationally constrained. It is unclear if SNRs can positively or negatively affect clouds star formation potential. We have studied the dense gas…