Starburst Wind from the Nucleus of NGC 7714
Abstract
High-resolution optical spectroscopic observations and infrared spectroscopy have been made of the starburst-nucleus galaxy NGC 7714. From the detailed investigation of the velocity field of ionized gas, we find the noncircular motion of the nuclear emitting region. The isovelocity map, derived from the Hα emission, clearly shows that slowly rotating emission-line regions lie along the perturbed disk (or the bar structure). This can be interpreted by an outward flow from the starburst nucleus with the conservation of angular momentum. The isovelocity map of the [N II] gas strongly suggests the presence of bipolar wind nearly perpendicular to the above slowly rotating clouds. This direction of the bipolar wind is identical to the major axis of the double radio lobe discovered by Weedman et al. (1981), implying that the optical emission-line gas is physically associated with the radio plasma. The kinetic energy of the expanding region, 9 X 10^53^ erg, may be supplied from both 10^4^ supernova events and 10^4^ OB stars in the starburst nucleus. The infrared spectroscopic observations lead to a marginal detection of H_2_ ν = 1-0 S(1) emission, giving a H_2_ mass of about 430 M_sun_ at most. The observed flux of Brackett γ emission requires the number of 1 X 10^4^ O5 stars as ionization sources in the circumnuclear region. Combining with IRAS observations and other information, we discuss the circumnuclear gaseous contents.
- Publication:
-
The Astronomical Journal
- Pub Date:
- May 1988
- DOI:
- 10.1086/114735
- Bibcode:
- 1988AJ.....95.1378T
- Keywords:
-
- Emission Spectra;
- Galactic Nuclei;
- Infrared Astronomy Satellite;
- Infrared Spectroscopy;
- Starburst Galaxies;
- Stellar Winds;
- Far Infrared Radiation;
- H Alpha Line;
- Ionized Gases;
- Molecular Gases;
- Astrophysics;
- RADIO SOURCES: GALAXIES;
- GALAXIES: SEYFERT