High angular resolution spectroscopic and polarimetric imaging of the galactic center in the near-infrared
Citations Over TimeTop 10% of 1995 papers
Abstract
We present improved 0.15 sec resolution K-band (2.2 micrometers) maps of the central 0.5 pc of the Galaxy as well as, for the first time, 0.2 sec J-band (1.25 micrometers) images, 0.2 sec K-band polarimetry, and 0.4 sec images in the 2.058 micrometer He 1 emission and 2.29 micrometers CO band head absorption features. The new K-band maps reach K magnitudes of about 16 and resolve the previously found object at the position of the radio source Sgr A*(R) into a small cluster of compact sources. With one exception, their polarizations are similar to other sources in its vicinity and thus are probably caused by antisotropic foreground dust extinction in the Galactic plane. The Sgr A*(IR) complex does not exhibit any significant flux density variations at 2.2 micrometers on timescales of minutes or years. We therefore interpret Sgr A*(IR) as a small local clustering of luminous stars (MK approximately equal to -3) near/at the position of the compact radio source. The central IRS 16 complex and the bright source IRS 13 are dominated by bright luminous He 1 stars and confirm the cluster of about a dozen He 1 stars found by Krabbe et al. (1991). There are also a dozen sources with K less than or equal to 12.5 exhibiting CO band head absorption within a radius of 10 sec of Sgr A*(IR). The drop in CO band head strength found by Sellgren et al. (1990) thus is most likely not caused by the disappearance of CO sources but by the additional presence of the bright early-type stars.
Related Papers
- → 10.7. Absorption columns with bright X-ray sources near the galactic center: — mass estimation in the Galactic center region(1998)3 cited
- → Large bea observations of the galatic center at 150, 200, and 300 μm(1982)2 cited
- → Large-Scale Ejection Structures in the Galactic Center(1989)2 cited
- Large beam observations of the galactic center at 150, 200, and 300 microns(1982)
- Large beam observations of the galactic center at 150, 200, and 300 microns(1982)