Related papers: HII regions and high-mass starless clump candidate…

We examine the effects of ionization, radiation pressure and main sequence winds from massive stars on self-gravitating, clumpy molecular clouds, thereby modeling the formation and pre-supernova feedback of massive star clusters. We find…

Based on a multiwavelength study, the ISM around the HII region Sh2-173 has been analyzed. The ionized region is clearly detected in the optical and in the radio continuum images. The analysis of the HI data shows a region of low emissivity…

We build, as far as theory will permit, self consistent model HII regions around central clusters of aging stars. These produce strong emission line diagnostics applicable to either individual HII regions in galaxies, or to the integrated…

The study of molecules and their chemistry in star-forming regions is fundamental to understand the physical process occurring in such regions. The HCN and HNC J=1-0 emissions were used to derive their integrated line intensities (I), to…

The southern Galactic high mass star-forming region, G351.6-1.3, is a HII region-molecular cloud complex with a luminosity of 2.0 x 10^5 L_sun, located at a distance of 2.4 kpc. In this paper, we focus on the investigation of the associated…

We study the formation and evolution of HII regions around the first stars formed at z=10-30. We use a one-dimensional Lagrangian hydrodynamics code which self-consistently incorporates radiative transfer and non-equilibrium primordial gas…

It has been proposed that some hot molecular cores (HMCs) harbor a young embedded massive star, which heats an infalling envelope and accretes mass at a rate high enough to ``choke off'' an incipient HII region. This class of HMCs would…

We analyse the internal dynamics of star-forming HII regions and their efficiency in interacting with the ISM. We use GHaFaS (Fabry-Perot) data of the nearby spiral galaxy M83 to perform multiple-Gaussian fitting to the integrated Halpha…

We analytically investigate the formation of an HII region in the accreting envelope of a newborn star. Special care is taken to examine the role of ionizing radiation force. This effect modifies velocity and density distributions and…

We analyze the dynamical expansion of the HII region, photodissociation region, and the swept-up shell, solving the UV- and FUV-radiative transfer, the thermal and chemical processes in the time-dependent hydrodynamics code. Following our…

HI in galaxies traces the fuel for future star formation and reveals the effects of feedback on neutral gas. Using a statistically uniform, HI-selected sample of 565 galaxies from the ALFALFA H-alpha survey, we explore HI properties as a…

Magnetic fields are ubiquitous and essential in star formation. In particular, their role in regulating formation of stars across diverse environments like HII regions needs to be well understood. In this study, we present magnetic field…

The formation of massive stars may take place at relatively low accretion rates over a long period of time if the accretion can continue past the onset of core hydrogen ignition. The accretion may continue despite the formation of an…

Using B, R, and H-alpha images of roughly equal-sized samples of low surface brightness (LSB) and high surface brightness (HSB) galaxies (~40 galaxies apiece), we have explored the dependence of HII region properties on local and global…

We present in here the exploration of the physical properties of the sample of HII regions and aggregations of the last HII regions catalog of the CALIFA survey. This sample comprises the optical spectroscopic properties of more than…

The expansion of HII regions can trigger the formation of stars. An overdensity of young stellar objects (YSOs) is observed at the edges of HII regions but the mechanisms that give rise to this phenomenon are not clearly identified.…

We study the structure of the medium surrounding sites of high-mass star formation to determine the interrelation between the HII regions and the environment from which they were formed. The density distribution of the surroundings is key…

Using infrared to (sub)millimeter data from Spitzer, Herschel, the James Clerk Maxwell Telescope, and the IRAM 30-m telescope, we conducted an unbiased survey of the massive dense cores (MDCs) in the Cygnus X molecular cloud complex, aimed…

Stellar feedback is needed to produce realistic giant molecular clouds (GMCs) and galaxies in simulations, but due to limited numerical resolution, feedback must be implemented using subgrid models. Observational work is an important means…

We present a photometric study of the stars in ionizing star clusters embedded in several giant HII regions of M33 (CC93, IC 142, NGC 595, MA2, NGC 604 and NGC 588). Our photometry are based on the HST-WFPC2 images of these clusters.…