Narrow-band imaging and velocity maps of young stellar objects - Initial results

We present new results obtained in frames of the Byurakan Narrow Band Imaging Survey (BNBIS). Observations were carried out with upgraded 1 m Schmidt telescope of Byurakan Observatory. Main task of this survey is to search and to study the new Herbig-Haro objects and collimated outflows using narrow-band Hα and [S ii] images of some fields in dark clouds of Galaxy. And, because, Herbig-Haro objects are the main indicators of active starformation processes to fined regions where going on active starformation processes. Main targets of this survey are R associations, young stellar objects associated with compact reflection nebulae, but here we will mainly focused on deeply embedded infrared sources in molecular clouds. During this survey we plan to significantly expand the list of HH objects by using the high quantum efficiency of the system and the telescopes high focal ratio (F/2), which allows detecting low surface brightness objects as well as large field of view of Schmidt telescope.

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Dynamics of jet/outflow driven by high-mass young stellar object revealed by KaVA 22 GHz water maser observations

Proceedings of the International Astronomical Union ◽

10.1017/s174392131701167x ◽

2017 ◽

Vol 13 (S336) ◽

pp. 303-304

Author(s):

Jungha Kim ◽

Tomoya Hirota ◽

Kee-Tae Kim ◽

Koichiro Sugiyama ◽

Keyword(s):

Dynamical Evolution ◽

Young Stellar Objects ◽

High Mass ◽

First Year ◽

Stellar Objects ◽

Large Program ◽

Molecular Lines ◽

Water Masers ◽

Initial Results ◽

Water Maser

AbstractWe have started survey observations of the 22 GHz water maser sources associated with high-mass young stellar objects (HM-YSOs) as a part of the KaVA (KVN and VERA Array) large program (LP). The aim of our LP is to understand dynamical evolution of jets/outflows from HM-YSOs by analyzing 3D velocity structures of water maser features. In the first year (2016-2017), an imaging survey toward 25 HM-YSOs has been conducted and the 22 GHz water masers are detected toward 21 sources. Spatial distributions of maser features for individual sources are mapped. To complement physical properties in the vicinity of HM-YSOs, we have carried out ALMA cycle 3 observations of thermal molecular lines and continuum emissions toward 11 selected samples. Summary of the KaVA first year observations and the initial results from the ALMA toward one of our targets, G25.82-0.17, are reported.

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The Spitzer Survey of the Large Magellanic Cloud: SAGE, A Review of Initial Results

Publications of the Astronomical Society of Australia ◽

10.1071/as07048 ◽

2008 ◽

Vol 25 (3) ◽

pp. 149-153 ◽

Cited By ~ 3

Author(s):

M. Meixner

Keyword(s):

Interstellar Medium ◽

Mass Loss ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Young Stellar Objects ◽

Stellar Objects ◽

Evolved Stars ◽

Initial Results ◽

Ism Dust ◽

Sage Data

AbstractWe have performed a uniform and unbiased imaging survey of the Large Magellanic Cloud, using the IRAC and MIPS instruments on board the Spitzer Space Telescope. This Spitzer survey of the Large Magellanic Cloud is surveying the agents of a galaxy's evolution (SAGE), the interstellar medium and stars. The SAGE data are nonproprietary and the team has been creating catalogs and improved images for use by the astronomical community. This paper highlights some of the initial results being published by the SAGE team covering the topics of evolved stars and their mass-loss return to the ISM, young stellar objects and the properties of the ISM dust.

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Accretion Signatures on Massive Young Stellar Objects

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314007327 ◽

2014 ◽

Vol 9 (S307) ◽

pp. 431-436

Author(s):

F. Navarete ◽

A. Damineli ◽

C. L. Barbosa ◽

R. D. Blum

Keyword(s):

Massive Star ◽

Narrow Band ◽

Massive Stars ◽

Young Stellar Objects ◽

Continuum Emission ◽

Stellar Clusters ◽

Low Mass Stars ◽

Stellar Objects ◽

Low Mass ◽

The Continuum

AbstractWe present preliminary results from a survey of molecular H2 (2.12 μm) emission in massive young stellar objects (MYSO) candidates selected from the Red MSX Source survey. We observed 354 MYSO candidates through the H2 S(1) 1-0 transition (2.12 μm) and an adjacent continuum narrow-band filters using the Spartan/SOAR and WIRCam/CFHT cameras. The continuum-subtracted H2 maps were analyzed and extended H2 emission was found in 50% of the sample (178 sources), and 38% of them (66) have polar morphology, suggesting collimated outflows. The polar-like structures are more likely to be driven on radio-quiet sources, indicating that these structures occur during the pre-ultra compact H ii phase. We analyzed the continuum images and found that 54% (191) of the sample displayed extended continuum emission and only ~23% (80) were associated to stellar clusters. The extended continuum emission is correlated to the H2 emission and those sources within stellar clusters does display diffuse H2 emission, which may be due to fluorescent H2 emission. These results support the accretion scenario for massive star formation, since the merging of low-mass stars would not produce jet-like structures. Also, the correlation between jet-like structures and radio-quiet sources indicates that higher inflow rates are required to form massive stars in a typical timescale less than 105 years.

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Billions of stars: the near infrared view of the Plane with UKIDSS and VISTA

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310011579 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 779-779 ◽

Cited By ~ 1

Author(s):

Philip W. Lucas ◽

David Samuel

Keyword(s):

Star Formation ◽

Globular Clusters ◽

Visual Inspection ◽

Near Infrared ◽

Galactic Plane ◽

Young Stellar Objects ◽

Stellar Objects ◽

Star Formation Regions ◽

Initial Results ◽

Cross Match

AbstractThe UKIDSS Galactic Plane Survey (GPS) is surveying the northern and equatorial plane in the J, H and K bands. Here we report initial results from searches for new clusters and star formation regions. 248 clusters have been detected by our Bayesian search, of which 127 are new. A visual inspection of the images is also proving successful. A cross match with Spitzer-GLIMPSE to find clusters of Young Stellar Objects is being attempted. No new globular clusters are detected except for two likely candidates already detected by Mercer et al. in GLIMPSE.

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New Capabilities of One-Meter Schmidt Telescope of the Byurakan Astrophysical Observatory after Modernization

Communications of the Byurakan Astrophysical Observatory ◽

10.52526/25792776-2017.1-92 ◽

2017 ◽

pp. 92-101

Author(s):

T. Movsessian ◽

S. Dodonov ◽

V. Gabrielyan ◽

S. Kotov ◽

M. Gevorgyan

Keyword(s):

Narrow Band ◽

Young Stellar Objects ◽

Special Astrophysical Observatory ◽

First Year ◽

Stellar Content ◽

Schmidt Telescope ◽

Stellar Objects ◽

Intermediate Band ◽

Byurakan Astrophysical Observatory ◽

Test Operation

Within the framework of cooperation between Byurakan Astrophysical Observatory and Special Astrophysical Observatory during 2013–2015 y the 1-m Schmidt telescope of the Byurakan Astrophysical was upgraded. We completely redesigned the control system of the telescope: we replaced the actuating mechanisms, developed telescope control software, and made the guiding system. In the Special Astrophysical Observatory the 4k×4k Apogee (USA) liquid-cooled CCD was reworked and prepared. Detector was mounted in the focus of the telescope and provides 1 degree field of view with pixel-size of 0.868, and RON∼11e−. The detector is equipped with a turret with 5 holes for filters. The 20 intermediate-band filters (FWHM= 250A) uniformly covering the 4000–9000 AA wavelength range, five broadband filters (u, g, r, i, z SDSS), and three narrow-band filters. During the first year of test operation of the 1-m telescope we performed pilot observations within the framework of three programs: search for young stellar objects, AGN evolution, and stellar composition of galaxy disks. We confirmed the possibility of efficiently selecting of young objects using observations performed in narrow-band Hα and [S II]filters and the intermediate-band 7500̊Afilter.Three-hours long exposures with SDSS g, r, and i band filters allow us to reach the surface brightness level of 28m from square arcsecond when investigating the stellar content of galaxy disks for a sample of nine galaxies. We used observations performed with the 1-m telescope in five broadband (SDSS u, g, r, i, and z) and 15 intermediate-band filters (4000–7500A) to construct a sample of quasar candidates with 0.5<z<5(330 objects) in about one-sq. degree SA 68 field complete down to RAB=23m. Spectroscopic observations of 29 objects (19.m5<R<22m) carried out at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences confirmed the quasar nature of 28 objects.

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