Dust and Ionized Gas in NGC 3607
Abstract
We report the detection of a broad dust ring in the X-ray-bright elliptical galaxy NGC 3607, the dominant member of a nearby group of galaxies. The inner radius of the ring is ~1.3 kpc from the nucleus and has a width of ~0.75 kpc. The maximum extinction corresponds to E(B - V) = 0.12 +/- 0.023. We also confirm the existence of bright Hα nebulosity around the nuclear region of the galaxy, just inside the dust ring. The luminosity in Hα is ~1.5 x 10^40^ ergs s^-1^. The estimated amount of neutral hydrogen in the galaxy is ~4 X 10^7^ M_sun_ and ionized hydrogen ~1.1 x 10^5^ M_sun_. We rule out Hα emission due to cooling flow, heat conduction from hot gas to the cold gas, photoionization by post-AGB stars or an active nucleus, and suggest that photoionization by young stars is the most plausible cause. We also suggest that the dust and associated gas are acquired from an interacting neighbor NGC 3608. The results are based on CCD surface photometry of the galaxy carried out using the broad-band filters V and A and a narrow-band filter appropriate for the redshifted Hα + [N II] emission.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1994
- DOI:
- 10.1086/173920
- Bibcode:
- 1994ApJ...424..638S
- Keywords:
-
- Cosmic Dust;
- Ellipticity;
- H Alpha Line;
- Hydrogen;
- Interstellar Extinction;
- Ionized Gases;
- Photoionization;
- Astronomical Photometry;
- Charge Coupled Devices;
- Imagery;
- Nitrogen;
- Optical Fibers;
- Red Shift;
- Reflecting Telescopes;
- Ring Structures;
- X Ray Sources;
- Astrophysics;
- GALAXIES: ELLIPTICAL AND LENTICULAR;
- CD;
- GALAXIES: INDIVIDUAL NGC NUMBER: NGC 3607;
- GALAXIES: ISM;
- RADIATION MECHANISMS: THERMAL;
- X-RAYS: GALAXIES