Young Stellar Nuclei in Lenticular Galaxies: NGC 5574 and NGC 7457

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Galaxies: Evolution, Galaxies: Individual: Ngc Number: Ngc 5574, Galaxies: Individual: Ngc Number: Ngc 7457, Galaxies: Kinematics And Dynamics, Galaxies: Nuclei, Galaxies: Structure

Scientific paper

The stellar population properties in the centers of NGC 5574 and NGC 7457 (two lenticular galaxies previously shown to have radially homogeneous blue optical-band colors) are studied by means of integral-field spectroscopy. The compact nuclei of the galaxies appear to be chemically distinct: in NGC 5574 the nucleus is distinguished by a higher than solar iron-to-magnesium ratio, and in NGC 7457 a drop of mean stellar metallicity by a factor of 2 exists between the nucleus and the bulge. Both galaxies demonstrate a rather young mean luminosity-weighted age of the stellar populations in the bulges, not older than 5-7 Gyr; however, the chemically distinct nuclei are still younger, 2-2.5 Gyr old. The kinematics of the stars in the center of NGC 5574 are probably affected by the influence of its global bar. The compact core of NGC 7457, with a radius of about 1.5", shows a visible counterrotation; a combined analysis of the photometric and kinematical two-dimensional maps allows us to conclude that the core rotates axisymmetrically, but its rotation plane is inclined to the main symmetry plane of the galaxy. The stellar velocity dispersion in the centers of both galaxies is anomalously low: 60-80 km s-1. Partly based on observations collected with the 6 m Bolshoi Teleskop Azimutal'nij at the Special Astrophysical Observatory of the Russian Academy of Sciences.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Young Stellar Nuclei in Lenticular Galaxies: NGC 5574 and NGC 7457 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 Young Stellar Nuclei in Lenticular Galaxies: NGC 5574 and NGC 7457, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Young Stellar Nuclei in Lenticular Galaxies: NGC 5574 and NGC 7457 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1660675

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.