Spectroscopic Study of NGC 1068 in the 3 micron Band
Abstract
The results of a near-infrared (2.9--4.1 mu m) spectroscopic observation of NGC 1068 is presented. We detected an absorption feature near to 3.4 mu m caused by an obscuring torus as well as a broad (FWHM ~ 300 km s(-1) ) Pfgamma emission line near to 3.75 mu m. The column density estimated from the 3.4 mu m feature corresponds to AV = 18--30 mag, which is far smaller than that inferred from hard X-ray observations. We conclude that the obscuring torus is highly concentrated to a thin disk, the thickness of which is less than 10(-1) pc, and that we view the obscuring torus from the exact edge-on direction. We have not detected the 3.3 mu m UIR (Unidentified InfraRed emission) feature in the central 3.8'' times3.8'' region. This result implies that starburst activity just outside of the obscuring torus is absent.
- Publication:
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Publications of the Astronomical Society of Japan
- Pub Date:
- February 1997
- DOI:
- 10.1093/pasj/49.1.69
- Bibcode:
- 1997PASJ...49...69I
- Keywords:
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- GALAXIES: INDIVIDUAL (NGC 1068);
- GALAXIES: SEYFERT;
- INFRARED: SPECTRA;
- INTERSTELLAR: DUST