697 datasets found

The emission nebula N66 is the brightest HII Region in the Small Magellanic Cloud (SMC), with the stellar association NGC 346 located in its center. The youthfulness of the...

Angular momentum (J) loss requires magnetic interaction between the forming star and both the circumstellar disk and the magnetically driven outflows. In order to test these...

The very young open cluster NGC 6383 centered on the O-star binary HD 159176 is an interesting place for studying the impact of early-type stars with strong radiation fields and...

Magnetic fields are at the heart of the observed stellar activity in late-type stars, and they are presumably generated by a dynamo mechanism at the interface layer (tachocline)...

Cometary globule 12 is a relatively little investigated medium- and low mass star forming region 210pc above the Galactic plane. This study sets out to discover the possibly...

The analysis of our deep UBVRIJHK photometry of Dolidze 25, located in the central area of the HII region Sh 2-284, reveals a young cluster with coeval MS and PMS populations of...

We performed an intensive photometric monitoring of the PMS stars falling in a field of about 10x10 arcminutes in the vicinity of the Orion Nebula Cluster (ONC). Photometric...

Rotational studies at a variety of ages and masses are important for constraining the angular momentum evolution of young stellar objects (YSO). Of particular interest are the...

While MLT-alpha^2D^ models are not available for lower metallicities, we extend to lower Z the NEMO-FST models, under the hypothesis that in such a way we are simulating the...

In close binary systems, the axial rotation and the mutual tidal forces of the component stars deform each other and destroy their spherical symmetry by means of the respective...

The disk-outflow connection is thought to play a key role in extracting excess angular momentum from a forming proto-star. Although jet rotation has been observed in a few...

The independence of the star formation processes with respect to the environmental conditions is controversial. In particular it is not clear whether star formation in the outer...

We study the nature of Gomez's Hamburger (IRAS 18059-3211), a nebula that has been proposed to be a post-AGB object. Such a classification has not been confirmed; instead, we...

High-resolution optical UBVRI and H{alpha} images obtained with ALFOSC mounted on the Nordic Optical Telescope (NOT), near-infrared JHK_S_ images obtained with NOTCam at the...

T Tauri stars exhibit variability on all timescales, whose origin is still debated. On WTTS the variability is fairly simple and attributed to long-lived, ubiquitous cool spots....

We wanted to determine the rotation parameters of GQ Lup A, thereby constraining the evolutionary history of the GQ Lup system. We have undertaken a photometric monitoring...

We present the basic ideas and first results from the project we are carrying out at present, the search for and characterisation of pre-main sequence (PMS) stars among the...

We report the results of a study the long term variability of Classical T Tauri stars (CTTS) over up to 20 years, characterize it from a set of statistical parameters and...

The aim of this paper is to provide a measurement of the mass accretion rate in a large, complete sample of objects in the core of the star forming region rho Oph. The sample...

Distance estimates based on low-resolution spectroscopy and Two Micron All Sky Survey (2MASS, Cat. ) J magnitudes are presented for 322 nearby candidates from Luyten's NLTT...