Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2010-08-13
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
19 pages, 10 figures. Accepted for publication in MNRAS
Scientific paper
We present deep spectroscopic data for a 24-object subsample of our full 41-object z~0.5 radio galaxy sample in order to investigate the evolution of the Fundamental Plane of radio galaxies. We find that the low-luminosity, FRI-type, radio galaxies in our sample are consistent with the local Fundamental Plane of radio galaxies defined by Bettoni et al. when corrected for simple passive evolution of their stellar populations. However, we find that the higher luminosity, FRII-type radio galaxies are inconsistent with the local Fundamental Plane if only passive evolution is considered, and find evidence for a rotation in the Fundamental Plane at z~0.5 when compared with the local relation. We show that neither passive evolution, nor a mass-dependent evolution in the mass-to-light ratio, nor an evolution in the size of the host galaxies can, by themselves, plausibly explain the observed tilt. However, we suggest that some combination of all three effects, with size evolution as the dominant factor, may be sufficient to explain the difference between the planes. We also find evidence for a correlation between host galaxy velocity dispersion and radio luminosity at the 97% significance level within our sub-sample, although further observations are required in order to determine whether this is different for the FRI and FRII radio sources. Assuming that the M_BH - sigma relation still holds at z~0.5, this implies that radio luminosity scales with black hole mass, in agreement with previous studies.
Dunlop James S.
Herbert Peter D.
Hill Gary J.
Jarvis Matt J.
McLure Ross J.
No associations
LandOfFree
The evolution of the Fundamental Plane of radio galaxies from z~0.5 to the present day 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 The evolution of the Fundamental Plane of radio galaxies from z~0.5 to the present day, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The evolution of the Fundamental Plane of radio galaxies from z~0.5 to the present day will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-503385