Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2009-03-16
Astrophys.J.698:1767-1770,2009
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
5 pages, 1 figure; ApJ, 698, 1767
Scientific paper
10.1088/0004-637X/698/2/1767
We have used a near-infrared nuclear spectrum (covering the Z, J, H and K bands) of the nucleus of NGC 4151 obtained with the Gemini Near-infrared Integral Field Spectrograph (NIFS) and adaptive optics, to isolate and constrain the properties of a near-IR unresolved nuclear source whose spectral signature is clearly present in our data. The near-IR spectrum was combined with an optical spectrum obtained with the Space Telescope Imaging Spectrograph which was used to constrain the contribution of a power-law component. After subtraction of the power-law component, the near-IR continuum is well fitted by a blackbody function, with $T=1285\pm50 $K, which dominates the nuclear spectrum -- within an aperture of radius 0$\farcs$3 -- in the near-IR. We attribute the blackbody component to emission by a dusty structure, with hot dust mass $M_{\rm HD}=(6.9\pm 1.5) \times10^{-4} {\rm M_\odot}$, not resolved by our observations, which provide only an upper limit for its distance from the nucleus of 4 pc. If the reddening derived for the narrow-line region also applies to the near-IR source, we obtain a temperature $T=1360\pm50 $K and a mass $M_{\rm HD}=(3.1\pm 0.7) \times10^{-4} {\rm M_\odot}$ for the hot dust. This structure may be the inner wall of the dusty torus postulated by the Unified Model or the inner part of a dusty wind originating in the accretion disk.
McGregor Peter J.
Riffel Rogemar A.
Storchi-Bergmann Thaisa
No associations
LandOfFree
The Dusty Nuclear Torus in NGC 4151: Constraints from Gemini Near-Infrared Integral Field Spectrograph Observations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Dusty Nuclear Torus in NGC 4151: Constraints from Gemini Near-Infrared Integral Field Spectrograph Observations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Dusty Nuclear Torus in NGC 4151: Constraints from Gemini Near-Infrared Integral Field Spectrograph Observations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-224156