The environment of low surface brightness galaxies

Abstract

Using the Early Data Release of the Sloan Digital Sky Survey (SDSS) we investigated the clustering properties of Low Surface Brightness (LSB) galaxies in comparison to normal, High Surface Brightness (HSB) galaxies. We selected LSB galaxies and HSB galaxies with well measured redshifts from the SDSS data base and performed three-dimensional neighbour counting analysis within spheres of radii between 0.8 Mpc and 8.0 Mpc. As a second analysis method we used an Nth neighbour analysis with N varying from one to ten galaxies. Our results show significant differences between the galaxy densities of LSB galaxies and HSB galaxies on scales from 2 to 5 Mpc. At scales larger than 5 Mpc LSB and HSB galaxies share the same clustering properties. In the pie-slice diagrams the LSB galaxies appear to favour the inner rims of filaments as defined by the HSB galaxies, with a couple of LSB galaxies even being located inside the voids. Our results support the idea of gas-rich LSB galaxies forming and developing in low density regions without many galaxy interactions and just now reaching the filaments of the large scale structure.