On the Redshift-Volume Measurement of the Cosmological Density Parameter
Abstract
We estimate the systematic bias due to galaxy evolution in the redshift-volume measurement of the cosmological deceleration parameter q_0_ which was recently done by Loh and Spillar. We classify galaxies into five types E/S0, Sab, Sbc, Scd, and Sdm which evolve with different star formation histories. Using the type-dependent evolution models of galaxies by Arimoto and Yoshii it is found that for z < 1 the bias is at most {DELTA}q_0_ = q_0_(true) - q_0_(apparent) ~ -0.2 if the well-defined parameters for local luminosity function of galaxies are adopted in the analysis. To determine q_0_ within this accuracy it is indispensable to obtain a sample of redshifts for galaxies as deep as m_lim_(6500 A) ~ 23 mag or m_lim_(8000 A) ~ 24 mag.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1989
- DOI:
- 10.1086/167983
- Bibcode:
- 1989ApJ...346...28Y
- Keywords:
-
- Computational Astrophysics;
- Cosmology;
- Galactic Evolution;
- Red Shift;
- Astronomical Spectroscopy;
- Galactic Structure;
- Luminosity;
- Spectral Energy Distribution;
- Star Formation;
- Astrophysics;
- COSMOLOGY;
- GALAXIES: EVOLUTION;
- GALAXIES: REDSHIFTS