Detection of features in the large-scale galaxy distribution from wide-angle samples of objective-prism spectra

Abstract

The authors demonstrate a promising new application of objective-prism spectra for the investigation of the large-scale distribution of galaxies. The method is based on the fact that galaxies with identifiable 4000 Å features on objective-prism plates are predominantly ellipticals and that such galaxies appear to delineate structure and clumpiness in the galaxy distribution. Results from a whole plate sample presented here reveal substantial structure in the particular field studied. The potential of this technique is that large-scale structure in the galaxy distribution may be highlighted and traced across many adjacent fields and to depths of &equiv;400 h<SUP>-1</SUP>Mpc by virtue of redshifts provided by the 4000 Å features. This can be done without the need for excessive amounts of observing time on large telescopes.