Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy

Details Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy

2007-08-17

arxiv.org/abs/0708.2365v2

MNRAS 384, 886 (2008)

Astronomy and Astrophysics

Astrophysics

24 pages, 16 figures. Accepted MNRAS version, minor corrections only, references added. Higher resolution version (1.3MB) is a

Scientific paper

10.1111/j.1365-2966.2007.12703.x

(abridged) We present near-infrared (NIR) adaptive optics imaging obtained with VLT/NACO and optical spectroscopy from the Southern African Large Telescope (SALT) of a luminous infrared galaxy (LIRG) IRAS 19115-2124. These data are combined with archival HST imaging and Spitzer imaging and spectroscopy, allowing us to study this disturbed interacting/merging galaxy, dubbed the Bird, in extraordinary detail. In particular, the data reveal a triple system where the LIRG phenomenon is dominated by the smallest of the components. One nucleus is a regular barred spiral with significant rotation, while another is highly disturbed with a surface brightness distribution intermediate to that of disk and bulge systems, and hints of remaining arm/bar structure. We derive dynamical masses in the range 3-7x10^10 M_solar for both. The third component appears to be a 1-2x10^10 M_solar mass irregular galaxy. The total system exhibits HII galaxy-like optical line ratios and strengths, and no evidence for AGN activity is found from optical or mid-infrared data. The star formation rate is estimated to be 190 M_solar/yr. We search for SNe, super star clusters, and detect 100-300 km/s outflowing gas from the Bird. Overall, the Bird shows kinematic, dynamical, and emission line properties typical for cool ultra luminous IR galaxies. However, the interesting features setting it apart for future studies are its triple merger nature, and the location of its star formation peak - the strongest star formation does not come from the two major K-band nuclei, but from the third irregular component. Aided by simulations, we discuss scenarios where the irregular component is on its first high-speed encounter with the more massive components.

Affiliated with

Also associated with

No associations

Rating

Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy 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 Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adaptive optics imaging and optical spectroscopy of a multiple merger in a luminous infrared galaxy will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-5995