Near-Infrared Array Images of Low-Luminosity IRAS Sources in Dark Clouds

1988 ◽  
pp. 111-121 ◽  
Author(s):  
H. Zinnecker
Keyword(s):  
Near Infrared ◽  
Dark Clouds ◽  
Infrared Array

scholarly journals Line observations of the 30-Dor complex and N159A5 with the MPE imaging NIR spectrometer FAST

1991 ◽  
Vol 148 ◽  
pp. 205-206 ◽  
Author(s):  
A. Krabbe ◽  
J. Storey ◽  
V. Rotaciuc ◽  
S. Drapatz ◽  
R. Genzel
Keyword(s):  
Spatial Resolution ◽  
Molecular Hydrogen ◽  
Near Infrared ◽  
Large Magellanic Cloud ◽  
Magellanic Cloud ◽  
Emission Lines ◽  
Resolving Power ◽  
Max Planck ◽  
First Time ◽  
Infrared Array

Images with subarcsec spatial resolution in the light of near-infrared atomic (Bry) and molecular hydrogen H2 (S(1) v=1-0) emission lines were obtained for some extended, pointlike objects in the Large Magellanic Cloud (LMC) for the first time. We used the Max-Planck-Institut für extraterrestrische Physik (MPE) near-infrared array spectrometer FAST (image scale 0.8”/pix, spectral resolving power 950) at the ESO/MPI 2.2m telescope, La Silla. We present some results on the 30-Dor complex and N159A5.

Polarimetric and photometric observations of CB54, with analysis of four other dark clouds

2021 ◽  
Vol 503 (4) ◽  
pp. 5274-5290
Author(s):  
A K Sen ◽  
V B Il’in ◽  
M S Prokopjeva ◽  
R Gupta
Keyword(s):  
Magnetic Field ◽  
Near Infrared ◽  
Galactic Plane ◽  
Photometric Data ◽  
Dust Particles ◽  
Dark Cloud ◽  
Dark Clouds ◽  
High Polarization ◽  
Field Parallel ◽  
Photometric Observations

ABSTRACT We present the results of our BVR-band photometric and R-band polarimetric observations of ∼40 stars in the periphery of the dark cloud CB54. From different photometric data, we estimate E(B − V) and E(J − H). After involving data from other sources, we discuss the extinction variations towards CB54. We reveal two main dust layers: a foreground, E(B − V) ≈ 0.1 mag, at ∼200 pc and an extended layer, $E(B-V) \gtrsim 0.3$ mag, at ∼1.5 kpc. CB54 belongs to the latter. Based on these results, we consider the reason for the random polarization map that we have observed for CB54. We find that the foreground is characterized by low polarization ($P \lesssim 0.5$ per cent) and a magnetic field parallel to the Galactic plane. The extended layer shows high polarization (P up to 5–7 per cent). We suggest that the field in this layer is nearly perpendicular to the Galactic plane and both layers are essentially inhomogeneous. This allows us to explain the randomness of polarization vectors around CB54 generally. The data – primarily observed by us in this work for CB54, by A. K. Sen and colleagues in previous works for three dark clouds CB3, CB25 and CB39, and by other authors for a region including the B1 cloud – are analysed to explore any correlation between polarization, the near-infrared, E(J − H), and optical, E(B − V), excesses, and the distance to the background stars. If polarization and extinction are caused by the same set of dust particles, we should expect good correlations. However, we find that, for all the clouds, the correlations are not strong.

scholarly journals Near Infrared Polarimetry of Dark Clouds and Star Forming Regions - Two Micron Polarization Survey of T Tauri Stars

1990 ◽  
Vol 140 ◽  
pp. 327-328
Author(s):  
M. Tamura ◽  
S. Sato
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Near Infrared ◽  
Background Field ◽  
Star Forming ◽  
Dark Clouds ◽  
Star Forming Regions ◽  
Stellar Sources ◽  
Geometrical Relationship ◽  
The Magnetic Field

Infrared polarimetry is one of the most useful methods to delineate the magnetic field structure in dark clouds and star-forming regions, where the intracloud extinction is so large that optical polarimetry is inaccessible. We have been conducting a near-infrared polarization survey of background field stars and embedded sources toward nearby dark clouds and star-forming regions (Tamura 1988). Particularly, the magnetic field structure in the denser regions of the clouds are well revealed in Heiles Cloud 2 in Taurus, ρ Oph core, and NGC1333 region in Perseus (Tamura et al. 1987; Sato et al. 1988; Tamura et al. 1988). This survey also suggests an interesting geometrical relationship between magnetic field and star-formation: the IR polarization of young stellar sources associated with mass outflow phenomena is perpendicular to the magnetic fields. This relationship suggests a presence of circumstellar matter (probably dust disk) with its plane perpendicular to the ambient magnetic field. Combining with another geometrical relationship that the elongation of the denser regions of the cloud is perpendicular to the magnetic field, the geometry suggests that the cloud contraction and subsequent star-formation have been strongly affected by the magnetic fields. Thus, it is important to study the universality of such geometrical relationship between IR polarization of young stellar sources and magnetic fields. In this paper, we report the results on a 2 micron polarization survey of 39 T Tauri stars, 8 young stellar objects and 11 background field stars in Taurus dark cloud complex.

scholarly journals Near-Infrared Images of the Serpens Molecular Cloud Core

1989 ◽  
Vol 120 ◽  
pp. 227-230
Author(s):  
C. Eiroa ◽  
M. Casali
Keyword(s):  
Molecular Cloud ◽  
Large Scale ◽  
Near Infrared ◽  
Far Infrared ◽  
Infrared Images ◽  
Infrared Source ◽  
Stellar Objects ◽  
Dark Clouds ◽  
First Time ◽  
Cloud Core

ABSTRACT:Near-infrared images of the Serpens molecular cloud core have been carried out at UKIRT (Mauna Kea Observatory) using the infrared array camera, IRCAM. A large-scale diffuse nebulosity extending over the central part of the core is observed. Over 100 K-sources are detected in the 30 arc min2 cloud core. Some of them are PMS objects which were previously unknown. For the first time, a near-infrared counterpart of the far-infrared source Seroens FIRS1 has been detected. The 2.2 µm source appears as a point like object at the apex of an extended knotty, jet-like nebulosity oriented towards the northwest. In addition, a group of 11 stellar objects is seen in the position of the IR/radio source SVS4. These objects are embedded in a very faint nebulosity and form one of the densest clustering of young stars found in dark clouds.

Ammonia and Near-Infrared Observations of Southern Dark Clouds

1993 ◽  
Vol 10 (3) ◽  
pp. 236-240 ◽  
Author(s):  
T.L. Bourke ◽  
A.R. Hyland ◽  
G. Robinson ◽  
S.D. James
Keyword(s):  
Near Infrared ◽  
Infrared Imaging ◽  
Imaging System ◽  
Ammonia Emission ◽  
Infrared Images ◽  
Infrared Source ◽  
Visual Appearance ◽  
Infrared Observations ◽  
Dark Clouds ◽  
Ammonia Source

AbstractThe Parkes radio telescope has been used to search a list of small, dense southern dark clouds and Bok globules for ammonia emission at 23.7 GHz. The ammonia observations, together with IRAS data and the cloud’s visual appearance, have been used to determine a short list of dark clouds for observation with the infrared imaging system (IRIS) on the Anglo-Australian Telescope, in an attempt to determine the dust density distribution within the clouds. Near-infrared images of a number of the short listed clouds have been obtained with IRIS at J, H and K’. Preliminary results are reported for this ammonia survey, together with IRIS images of the strong ammonia source DC 297.7–2.8. Coincident with the dense ammonia core of this object is an IRAS ‘core’ source, IRAS 11590–6452 and an extremely interesting near-infrared source, which lies on the edge of the error ellipse of the IRAS source.

Single-Shot Spectral Sensor Based on a Multi-Pixel Near-Infrared Array

2020 ◽  
Author(s):  
Kaylee D. Hakkel ◽  
Maurangelo Petruzzella ◽  
Francesco Pagliano ◽  
Anne van Klinken ◽  
Fang Ou ◽  
...  
Keyword(s):  
Near Infrared ◽  
Single Shot ◽  
Infrared Array

scholarly journals A survey of circumstellar structure around young low mass stars

1991 ◽  
Vol 147 ◽  
pp. 345-352
Author(s):  
S. Terebey ◽  
C. A. Beichman ◽  
T. N. Gautier ◽  
J. J. Hester ◽  
P. C. Myers ◽  
...  
Keyword(s):  
Molecular Clouds ◽  
Near Infrared ◽  
Circumstellar Disk ◽  
Stellar Winds ◽  
Low Mass Stars ◽  
Show Evidence ◽  
Low Mass ◽  
Circumstellar Environments ◽  
Cloud Cores ◽  
Infrared Array

We present results from a near-infrared array, CO interferometer, and H2O maser interferometer survey of the circumstellar environments of 26 young low-luminosity embedded stars located in nearby molecular clouds. About 75% of the sample show evidence for stellar winds/outflows in the near-infrared or CO data indicating that most of these sources are in the early wind clearing phase of their evolution. Close to 15% are multiple on the scale of 20″, suggesting that fragmentation of their surrounding dense cloud cores is important before or during gravitational collapse. Roughly 10% have H2O maser emission and the kinematics imply the masers arise in gravitationally unbound gas (i.e., a stellar wind or outflow) rather than in a circumstellar disk.

The New Near Infrared Array Camera at the University of Rochester

1985 ◽  
Vol 97 ◽  
pp. 183 ◽  
Author(s):  
W. J. Forrest ◽  
A. Moneti ◽  
C. E. Woodward ◽  
J. L. Pipher ◽  
A. Hoffman
Keyword(s):  
Near Infrared ◽  
The University ◽  
Array Camera ◽  
Infrared Array
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