IMAGES II. A surprisingly low fraction of undisturbed rotating spiral disks at z~0.6: The morpho-kinematical relation 6 Gyrs ago

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Typos corrected, reference added

Scientific paper

10.1051/0004-6361:20079226

We present a first combined analysis of the morphological and dynamical properties for the Intermediate MAss Galaxy Evolution Sequence (IMAGES) sample. It is a representative sample of 52 z~0.6 galaxies with Mstell from 1.5 to 15 10^10Msun and possessing 3D resolved kinematics and HST deep imaging in at least two broad band filters. We aim at evaluate robustly the evolution of rotating spirals since z~0.6, as well as to test the different schemes for classifying galaxies morphologically. We used all the information provided by multi-band images, color maps and 2 dimensional light fitting to assign to each object a morphological class. We divided our sample between spiral disks, peculiar objects, compact objects and mergers. Using our morphological classification scheme, 4/5 of identified spirals are rotating disks and more than 4/5 of identified peculiar galaxies show complex kinematics, while automatic classification methods such as Concentration-Asymmetry and GINI-M20 severely overestimate the fraction of relaxed disk galaxies. Using this methodology, we find that the fraction of rotating spirals has increased by a factor ~ 2 during the last 6 Gyrs, a much higher fraction that found previously based on morphologies alone. These rotating spiral disks are forming stars very rapidly, doubling their stellar masses over the last 6 Gyrs, while most of their stars have been formed few Gyrs earlier, which reveals the presence of a large gas supply. Because they are likely the progenitors of local spirals, we can conjecture how their properties are evolving. Their disks show some evidence for an inside-out growth and the gas supply/accretion is not made randomly as the disk need to be stable in order to match the local disk properties.

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

IMAGES II. A surprisingly low fraction of undisturbed rotating spiral disks at z~0.6: The morpho-kinematical relation 6 Gyrs ago 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 IMAGES II. A surprisingly low fraction of undisturbed rotating spiral disks at z~0.6: The morpho-kinematical relation 6 Gyrs ago, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and IMAGES II. A surprisingly low fraction of undisturbed rotating spiral disks at z~0.6: The morpho-kinematical relation 6 Gyrs ago will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-645720

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