The local space density of dwarf galaxies
نویسنده
چکیده
We estimate the luminosity function of Ðeld galaxies over a range of 10 mag for ([22 \ M BJ \ [12 km s~1 Mpc~1) by counting the number of faint APM galaxies around Stromlo-APM redshift H 0 \ 100 survey galaxies at known distance. The faint end of the luminosity function rises steeply at M BJ B [15, implying that the space density of dwarf galaxies is at least 2 times larger than predicted by a Schechter function with Ñat faint-end slope. Such a high abundance of dwarf galaxies at low redshift can help explain the observed number counts and redshift distributions of faint galaxies without invoking exotic models for galaxy evolution. Subject headings : cosmology : observations È galaxies : distances and redshifts È galaxies : evolution È galaxies : luminosity function, mass function È surveys
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