Related papers: HI ``Tails'' from Cometary Globules in IC1396

We discuss recent observational and numerical work on tidal tails in globular clusters. Evidence of tidal tails has now been found in 16 Galactic globulars and 4 globulars in M31. Simulations indicate that mapping of these tidal tails over…

Galactic HI emission profiles in an area where several large-scale filaments at velocities ranging from -46 km/s to 0 km/s overlap were decomposed into Gaussian components. Eighteen families of components defined by similarities of center…

We present polarization images of Comet ISON (C/2012 S1) taken with the Hubble Space Telescope (HST) on UTC 2013 May 8 (rh = 3.81 AU, Delta = 4.34 AU), when the phase angle was alpha = 12.16 degrees. This phase angle is approximately…

We present a study of the distribution and kinematics of the neutral gas in the low-inclination Scd galaxy NGC 6946. The galaxy has been observed for 192 hours at 21-cm with the Westerbork Synthesis Radio Telescope. These are among the…

The characteristics of ionized and HI gas in the peculiar star/cluster complex in NGC 6946, obtained with the 6-m telescope (BTA) SAO RAS, the Gemini North telescope, and the Westerbork Synthesis Radio Telescope (WSRT), are presented. The…

We have mapped the velocity structure of the cometary compact HII region G29.96-0.02 using long-slit echelle spectra of the HI Br gamma line. This technique detects line emission over a much wider area at the necessary spatial resolution…

We have made an extensive survey of emission-line stars in the IC 1396 HII region to investigate the low-mass population of pre-main sequence (PMS) stars. A total of 639 H-alpha emission-line stars were detected in an area of 4.2 deg^2 and…

An extended HI cloud (VIRGOHI 21) with an HI mass of $\sim10^8$ M$_{\odot}$ and no apparent optical counterpart was recently discovered in the Virgo cluster. In order to understand the origin of physical properties of apparently isolated HI…

(Abridged) We present the results of three-dimensional radiation-hydrodynamics simulations of the formation and evolution of early HII/HeIII regions around the first stars. Cooling (by H2 and HD) and recollapse of the gas in the relic HII…

We present here our shape analysis method for a sample of 76 Galactic HII regions from MAGPIS 1.4 GHz data. The main goal is to determine whether physical properties and initial conditions of massive star cluster formation is linked to the…

Observational studies of HII region-molecular cloud interactions constrain models of feedback and quantify its impact on the surrounding environment. A recent hypothesis proposes that a characteristic spectral signature in ground state…

In the best observed spiral galaxies, the HI is observed to decline slowly with radius for up to 90% of the maximum extent, before experiencing a rapid truncation. Early models predicted that the outer parts of spirals would be fully…

We study the Large Magellanic Cloud HII region N 214C using imaging and spectroscopy obtained at the ESO New Technology Telescope. On the basis of the highest resolution images so far obtained of the OB association LH 110, we show that the…

A high quality, medium-resolution K-band spectrum has been obtained of the ultracompact HII region G29.96-0.02 with the Very Large Telescope (VLT). The slit was positioned along the symmetry axis of the cometary shaped nebula. Besides the…

Aims. We analyze the LBN 978 HII region in order to study the HII/molecular cloud interaction. Methods. We used the IAC-80 telescope to image the region with narrow-band filters and the Very Large Array to obtain a radio continuum map at…

Galaxies moving through the intracluster medium (ICM) of a cluster of galaxies can lose gas via ram pressure stripping. This stripped gas forms a tail behind the galaxy which is potentially observable. In this paper, we carry out…

Pillars and globules are present in many high-mass star-forming regions, such as the Eagle nebula (M16) and the Rosette molecular cloud, and understanding their origin will help characterize triggered star formation. The formation…

We investigated an isolated, globule-shaped object (0.37x0.11 pc), located near the centre of the Cygnus OB2 cluster and named proplyd #7 in optical observations. The source can be a massive star (with or without disc) with a HII region or…

HII regions are the ionized spheres surrounding high-mass stars. They are ideal targets for tracing Galactic structure because they are predominantly found in spiral arms and have high luminosities at infrared and radio wavelengths. In the…

We present a new, detailed, analysis of the spatial distribution of Galactic HII regions, exploiting a far richer database than used in previous analyses. Galactocentric distances have been derived for 550 objects. Distances from the Sun…