Related papers: A Luminous Blue Variable Star Interacting with a N…
We present mid-IR observations of the Galactic Luminous Blue Variable (LBV) HR Car and its associated nebula carried out with the Spitzer Space Telescope using both IRAC and IRS, as part of a GTO program aimed to study stellar ejecta from…
The Bubble Nebula (or NGC 7635) is a parsec-scale seemingly spherical wind-blown bubble around the relatively unevolved O star BD+60$^\circ$2522. The small dynamical age of the nebula and significant space velocity of the star suggest that…
We continue the search for luminous blue variables (LBVs) in Local Volume galaxies in order to study their fundamental parameters. In this paper, we report the discovery of two new LBVs in the dwarf irregular galaxy NGC 1156. Both stars…
Spitzer images of the luminous blue variable (LBV) candidate HD168625 reveal the existence of a bipolar nebula several times larger than its previously-known equatorial dust torus. The outer nebula of HD168625 has a full extent of about 80…
We investigate the dust associated with the supernova remnant (SNR) N49 in the Large Magellanic Cloud (LMC) as observed with the Herschel Space Observatory. N49 is unusually bright because of an interaction with a molecular cloud along its…
We have observed the clump G34.43+00.24 MM3 associated with an infrared dark cloud in DNC $J$=3--2, HN$^{13}$C $J$=3--2, and N$_2$H$^+$ $J$=3--2 with the Atacama Large Millimeter/submillimeter Array (ALMA). The N$_2$H$^+$ emission is found…
We describe a search for H-alpha emission-lined stars in M31, M33, and seven dwarfs in or near the Local Group (IC 10, NGC 6822, WLM, Sextans B, Sextans A, Pegasus and the Phoenix dwarf) using interference filter imaging with the KPNO and…
High resolution infrared imaging observations of the young Planetary Nebulae NGC 7027 and BD +303639, taken with the newly installed TIFR Infrared Camera-II (TIRCAM2) on 3.6m Devasthal Optical Telescope (DOT), ARIES, Nainital, are being…
We have observed a cluster forming clump (MM3) associated with the infrared dark cloud G34.43+00.24 in the 1.3 mm continuum and the CH3OH, CS, 13CS, SiO, CH3CH2CN, and HCOOCH3 lines with the Atacama Large Millimeter/submillimeter Array and…
We present a multiwavelength study of the filamentary infrared dark cloud (IRDC) G333.73+0.37. The region contains two distinct mid-infrared sources S1 and S2 connected by dark lanes of gas and dust. Cold dust emission from the IRDC is…
Luminous blue variables (LBVs) are evolved massive stars close to the Eddington limit, with a distinct spectroscopic and photometric variability having unsteady mass-loss rates. These stars show a considerable change in their surface…
We present the results of a new epoch of a long-term photometric monitoring of the variable planetary nebula IC~4997. The integral $UBV$ light curves display a continuing brightening of 0.$^{m}15$ in $V$, a slight rise (<0.$^{m}1$) in $B$,…
The most massive evolved stars (above 50 M_sun) undergo a phase of extreme mass loss in which their evolution is reversed from a redward to a blueward motion in the HRD. In this phase the stars are known as Luminous Blue Variables (LBVs)…
TIMMI2 diffraction-limited mid-infrared images of a multipolar proto-planetary nebula IRAS 16594-4656 and a young [WC] elliptical planetary nebula IRAS 07027-7934 are presented. Their dust shells are for the first time resolved (only…
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…
Luminous blue variables (LBVs) are expected to play an important role in massive stellar evolution as well as being the progenitors of some of the most luminous supernovae known. In this paper we provide a multiwavelength study of the…
We present the first interferometric detection of extragalactic NH_3(6,6) emission in the nearby galaxy IC 342 made using the VLA. The data have a resolution of 7.8''x 5.0'' and trace hot (T ~ 412 K) and dense (> 10^{4} cm^{-3}) molecular…
We are presenting here a study of the cold dust in the infrared ring nebula Gum 31. We aim at deriving the physical properties of the molecular gas and dust associated with the nebula, and investigating its correlation with the star…
The massive infrared dark cloud G0.253+0.016 projected 45pc from the Galactic centre contains ~10^5Msun of dense gas whilst being mostly devoid of observed star-formation tracers. To scrutinise the physical properties, dynamics and…
This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, linked to the Wolf-Rayet star HD168206 (WR 113), and its relation to other components of its local interstellar medium. We…