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The Mass Function of Void Galaxies in the SDSS Data Release 2

David M. Goldberg·Timothy D. Jones·Fiona Hoyle·Randall R. Rojas·Michael S. Vogeley·Michael R. Blanton
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Abstract

We estimate the Mass Function of void galaxies in the second public data release of the Sloan Digital Sky Survey from a sample of 1000 galaxies with local density contrasts of delta_v < -0.6. The galaxy sample is split into ellipticals and spirals using a color-Sersic index criteria. We estimate the virial masses of ellipticals using the measured spectral line-widths along with the observed size. Projection effects and uncertainties in halo properties make mass estimates of spirals more difficult. We use an inversion of the Tully-Fisher relation to estimate the isothermal rotational velocity, and introduce a scaling factor to estimate the halo extent. We then fit the measured mass function against a theoretical Press-Schechter model, and find that the distribution of galaxies in voids appears to be nearly unbiased compared to the mass.

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David M. Goldberg, Timothy D. Jones, Fiona Hoyle, Randall R. Rojas, Michael S. Vogeley, Michael R. Blanton. 2004-11-11. The Mass Function of Void Galaxies in the SDSS Data Release 2. https://doi.org/10.1086/427679

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