Related papers: Young massive stars and their environment in the m…
We present maps of the 850 micron and 450 micron continuum emission seen towards a sample of 68 high-mass protostellar candidates with luminosities ranging from 10^2.5 to 10^5 solar luminosity. Most of these candidate high-mass stars are in…
We use a 3D Monte Carlo radiative transfer code to study the projection of large shadows by circumstellar disks around young stellar objects on surrounding reflection nebulosity. It is shown that for a wide range of parameters a small…
We present our second set of results from our mid-infrared imaging survey of Milky Way Giant HII regions. We used the FORCAST instrument on the Stratospheric Observatory For Infrared Astronomy to obtain 20 and 37$\mu$m images of the central…
We demonstrate the unique capabilities of Herschel to study very young luminous extragalactic young stellar objects (YSOs) by analyzing a central strip of the Large Magellanic Cloud obtained through the HERITAGE Science Demonstration…
We present observations of the famous OH/IR star OH26.5+0.6 obtained using the Mid-Infrared Interferometric Instrument MIDI at the European Southern Observatory (ESO) Very Large Telescope Interferometer VLTI. The emission of the dusty…
We present near-IR VLT/ISAAC and mid-IR Spitzer/IRS spectroscopy of the young massive cluster in the W31 star-forming region. H-band spectroscopy provides refined classifications for four cluster members O stars with respect to Blum et al.…
We use 2MASS and MSX infrared observations, along with new molecular line (CO) observations, to examine the distribution of young stellar objects (YSOs) in the molecular cloud surrounding the halo HII region KR 140 in order to determine if…
Accretion in young stellar objects (YSOs) is at least partially episodic, i.e. periods with high accretion rates ('bursts') are interspersed by quiescent phases. These bursts manifest themselves as eruptive variability. Here we present a…
We are conducting a survey of several regions of high-mass star formation to assess their content and structure. The observations include Spitzer observations, ground-based optical and near-IR imaging surveys, and optical and IR spectra of…
Recent mid-infrared observations of young stellar objects have found significant variations possibly indicative of changes in the structure of the circumstellar disk. Previous models of this variability have been restricted to axisymmetric…
Time-domain studies of mid-infrared and submillimeter variability have shown that at least half of protostars are variable. We present a statistical analysis of mid-infrared variability among young stellar objects (YSOs) in the distant,…
The Wide-field Infrared Survey Explorer has uncovered a population of young stellar objects in the Western Circinus molecular cloud. Images show the YSOs to be clustered into two main groups that are coincident with dark filamentary…
We examine the properties of embedded clusters within 1 kiloparsec using new data from the Spitzer Space Telescope, as well as recent results from 2MASS and other ground-based near-infrared surveys. We use surveys of entire molecular clouds…
In this paper we present Spitzer Infrared Spectrograph spectroscopy for 14 intermediate-mass young stellar objects. We use Spitzer spectroscopy to investigate the physical properties of these sources and their environments. Our sample can…
Understanding the formation mechanisms of protoplanetary disks and multiple systems, and their pristine properties, is a key question for modern astrophysics. The properties of the youngest disks, embedded in rotating infalling protostellar…
We present results of gasdynamics+N-body constrained cosmological simulations of the Local Supercluster region (LSC; about 30/h Mpc around the Virgo cluster), which closely mimic the real Universe within 100 Mpc by imposing constraints from…
Recent studies have identified several young stellar objects (YSOs) which exhibit significant mid-infrared (mid-IR) variability. A wide range of physical mechanisms may be responsible for these variations, including changes in a YSO's…
We investigate the nature of the innermost regions of seven circumstellar disks around pre-main-sequence stars. Our object sample contains disks apparently at various stages of their evolution. Both single stars and spatially resolved…
The formation of massive stars and their arrival on the zero-age main-sequence occurs hidden behind dense clouds of gas and dust. In the giant Hii region NGC 3603, the radiation of a young cluster of OB stars has dispersed dust and gas in…
Using the infrared photometry data extracted from the 2MASS, IRAS and MSX databases, 50 suspected young stellar objects (YSOs) are selected from about 37500 infrared objects in the 3x3 deg area with the center at Galactic longitude 142.5…