A deep redshift survey of IRAS galaxies towards the boötes void

We have measured redshifts for a complete sample of galaxies detected by the Infrared Astronomical Satellite (IRAS) within 11°.5 of the center of the void in Bootes discovered by Kirshner et al. There are 12 IRAS galaxies within the void as defined by the above authors, seven of which were discovered in this survey. One of these has a companion at the same redshift. The resulting density of IRAS galaxies in the void is measured to be between 1/6 and 1/3 of the average density; the uncertainty is dominated by Poisson statistics. We find good agreement between the selection function and number density derived from the present sample and those derived from the all-sky sample of Strauss (1989). The optical spectra of the newly found galaxies in the void are typical of IRAS galaxies in the field. The large errors on quoted flux densities at the faint end of the IRAS Point Source Catalog can cause systematic selection biases, which may be an issue in deep large-scale surveys based on the IRAS database.