The 2dF Galaxy Redshift Survey: Constraints on Cosmic Star Formation History from the Cosmic Spectrum
- 20 April 2002
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 569 (2) , 582-594
- https://doi.org/10.1086/339477
Abstract
We present the first results on the history of star formation in the universe based on the "cosmic spectrum," in particular the volume-averaged, luminosity-weighted, stellar absorption-line spectrum of present-day galaxies from the 2dF Galaxy Redshift Survey. This method is novel in that, unlike previous studies, it is not an estimator based on total luminosity density. The cosmic spectrum is fitted with models of population synthesis, tracing the history of star formation before the epoch of the observed galaxies, using a method we have developed that decouples continuum and spectral line variations and is robust against spectrophotometric uncertainties. The cosmic spectrum can only be fitted with models incorporating chemical evolution, and it indicates that there was a peak in the star formation rate (SFR) in the past of at least 3 times the current value and that the increase back to z = 1, assuming it scales as (1 + z)β, has a strong upper limit of β < 5. We find, in the general case, that there is some model degeneracy between star formation at low and high redshift. However, if we incorporate previous work on star formation at z < 1, we can put strong upper limits on the star formation rate at z > 1: e.g., if β > 2, then the SFR for 1 < z < 5 scales as (1 + z)α, with α < 2. This is equivalent to stating that no more than 80% of stars in the universe formed at z > 1. Our results are consistent with the best-fit results from compilations of cosmic SFR estimates based on UV luminosity density, which yield 1.8 < β < 2.9 and -1.0 < α < 0.7, and are also consistent with estimates of Ωstars based on the K-band luminosity density.Keywords
All Related Versions
This publication has 41 references indexed in Scilit:
- The 2dF Galaxy Redshift Survey: spectra and redshiftsMonthly Notices of the Royal Astronomical Society, 2001
- The 2dF galaxy redshift survey: near-infrared galaxy luminosity functionsMonthly Notices of the Royal Astronomical Society, 2001
- The Luminosity Function of Galaxies in SDSS Commissioning DataThe Astronomical Journal, 2001
- The Local Space Density of Sb‐Sdm Galaxies as Function of Their Scale Size, Surface Brightness, and LuminosityThe Astrophysical Journal, 2000
- A flat Universe from high-resolution maps of the cosmic microwave background radiationNature, 2000
- Evidence for a Gradual Decline in the Universal Rest-Frame Ultraviolet Luminosity Density for [CLC][ITAL]z[/ITAL][/CLC] < 1The Astronomical Journal, 1999
- The star formation history of the Hubble sequence: spatially resolved colour distributions of intermediate-redshift galaxies in the Hubble Deep FieldMonthly Notices of the Royal Astronomical Society, 1999
- The 2dF Galaxy Redshift SurveyPublished by Springer Nature ,1999
- The Evolution of the Global Star Formation History as Measured from the Hubble Deep FieldThe Astrophysical Journal, 1997
- A cosmologically significant population of galaxies dominated by very young star formationThe Astrophysical Journal, 1988