Astronomy and Astrophysics – Astronomy
Scientific paper
Aug 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994apj...431l..13l&link_type=abstract
The Astrophysical Journal, Part 2 - Letters, vol. 431, no. 1, p. L13-L16
Astronomy and Astrophysics
Astronomy
25
Elliptical Galaxies, Galactic Nuclei, Infrared Astronomy, Interacting Galaxies, Kinematics, Molecular Gases, Near Infrared Radiation, Red Giant Stars, Star Formation, Starburst Galaxies, Absorption Spectra, Emission Spectra, Radial Velocity, Radio Emission, Stellar Luminosity
Scientific paper
We have used the 2.3 micron bandhead of CO to measure the kinematics of the red stellar population in the nucleus of the luminous galaxy NGC 6240, the near-infrared spectrum of which is dominated by lines of shocked gas. With this manifest evidence for dissipative effects in the gas, it is such stellar velocity dispersion that is most unambiguously indicative of gravitational potential. We find a nuclear velocity dispersion sigma = 350 km/sec which is considerably larger than that seen in any gaseous component of this galaxy. At least one partner in this merger must therefore have been very massive, with MB approximately -23. In view of conventional wisdom that the high luminosity of NGC 6240 derives from star formation, it is suprising that we find M/L to be of order unity. While there seems to be little question that star formation is taking place in this interacting system, this high M/L calls into question the importance of star formation in the luminosity budget of the galaxy. In particular, it seems likely that the red starlight in NGC 6240 is produced by giants rather than a population of young red supergiants. This brings into question the (now reflexive) association of relatively deep CO bands in galaxies (which are conspicuously strong in NGC 6240) with recent star formation.
Gaffney Niall I.
Lester Dan F.
No associations
LandOfFree
Stellar kinematics in the nucleus of NGC 6240: A massive galaxy revealed 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 Stellar kinematics in the nucleus of NGC 6240: A massive galaxy revealed, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stellar kinematics in the nucleus of NGC 6240: A massive galaxy revealed will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1494566