Voids in the SDSS Galaxy Survey

Understand

Using the method of searching for arbitrary shaped voids in the distribution of volume-limited samples of galaxies from the DR5 SDSS survey, we have identified voids and investigated their characteristics and the change in these characteristics with decreasing Mlim - the upper limit on the absolute magnitude of the galaxies involved in the construction of voids.

• The total volume of the 50 largest voids increases with decreasing Mlim with a break near Mr* = -20.44 for SDSS galaxies.
• The mean density contrast in voids increases with decreasing Mlim also with a weak break near M*.
• The exponent of the dependence of the volume of a void on its rank increases significantly with decreasing Mlim starting from Mlim ~ -20.4 in the characteristic range of volumes, which reflects the tendency for greater clustering of brighter galaxies.