Astronomy and Astrophysics – Astrophysics
Scientific paper
1997-02-27
Astrophys.J.484:581-601,1997
Astronomy and Astrophysics
Astrophysics
34 pages (Latex text + tables), 18 pages of postscript figures; Accepted for publication in The Astrophysical Journal
Scientific paper
10.1086/304381
The weak radio source LBDS 53W091 is associated with a very faint (R approx. 24.5) red (R-K approx. 5.8) galaxy. Long spectroscopic integrations with the W. M. Keck telescope have provided an absorption-line redshift, z=1.552 +/- 0.002. The galaxy has a rest frame ultraviolet spectrum very similar to that of an F6V star, and a single-burst old stellar population that matches the IR colors, the optical energy distribution and the spectral discontinuities has a minimum age of 3.5 Gyr. We present detailed population synthesis analyses of the observed spectrum in order to estimate the time since the last major epoch of star formation. We discuss the discrepancies in these estimates resulting from using different models, subjecting the UV spectrum of M32 to the same tests as a measure of robustness of these techniques. The models most consistent with the data tend to yield ages at z=1.55 of >3.5Gyr, similar to that inferred for the intermediate-age population in M32. Depending upon the assumed Hubble constant and the value of Omega_0, only certain cosmological expansion times are consistent with the age of LBDS 53W091; in particular, for Omega_0=1, only models with H_0 < 45 km/s/Mpc are permitted. For H_0=50 km/s/Mpc and Omega_0=0.2, we derive a formation redshift, z_f >= 5.
Dey Arjun
Dunlop James
Jimenez Raul
Peacock John
Spinrad Hyron
No associations
LandOfFree
LBDS 53W091: An Old red Galaxy at z=1.552 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 LBDS 53W091: An Old red Galaxy at z=1.552, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and LBDS 53W091: An Old red Galaxy at z=1.552 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-391945