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Resolved Mid-IR Emission in the Narrow Line Region of NGC 4151

James T. Radomski·Robert K. Pina·Christopher Packham·Charles M. Telesco·James M. De Buizer·R. Scott Fisher·A. Robinson
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Abstract

We present subarcsecond resolution mid infrared images of NGC 4151 at 10.8 micron and 18.2 micron. These images were taken with the University of Florida mid-IR camera/spectrometer OSCIR at the Gemini North 8-m telescope. We resolve emission at both 10.8 micron and 18.2 micron extending ~ 3.5" across at a P.A. of ~ 60 degrees. This coincides with the the narrow line region of NGC 4151 as observed in [OIII] by the Hubble Space Telescope. The most likely explanation for this extended mid-IR emission is dust in the narrow line region heated by a central engine. We find no extended emission associated with the proposed torus and place an upper limit on its mid-IR size of less than or equal to ~ 35 pc.

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James T. Radomski, Robert K. Pina, Christopher Packham, Charles M. Telesco, James M. De Buizer, R. Scott Fisher, A. Robinson. 2002-12-12. Resolved Mid-IR Emission in the Narrow Line Region of NGC 4151. https://doi.org/10.1086/367612

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