The Sloan Digital Sky Survey u-band Galaxy Survey: luminosity functions and evolution


Baldry IK, Glazebrook K, Budavári T, Eisenstein DJ, Annis J, Bahcall NA, Blanton MR, Brinkmann J, Csabai I, Heckman TM, et al. The Sloan Digital Sky Survey u-band Galaxy Survey: luminosity functions and evolution. Monthly Notices of the Royal Astronomical Society. 2005;358 :441-456.

Date Published:

April 1, 2005


We construct and analyse a u-band selected galaxy sample from the SloanDigital Sky Survey (SDSS) Southern Survey, which covers275deg2. The sample includes 43223 galaxies withspectroscopic redshifts in the range 0.005 < z < 0.3 and with 14.5< u < 20.5. The signal-to-noise (S/N) ratio in the u-bandPetrosian aperture is improved by co-adding multiple epochs of imagingdata and by including sky-subtraction corrections. Luminosity functionsfor the near-UV 0.1u band (λ~ 322 +/- 26nm) aredetermined in redshift slices of width 0.02, which show a highlysignificant evolution in M* of -0.8 +/- 0.1 mag between z= 0 and 0.3;with M*-5 logh70=-18.84 +/- 0.05 (AB mag), logφ*=-2.06+/- 0.03 (h370Mpc-3) andlogρL= 19.11 +/- 0.02(h70WHz-1Mpc-3) at z= 0.1. Thefaint-end slope determined for z < 0.06 is given by α=-1.05 +/-0.08. This is in agreement with recent determinations from the GalaxyEvolution Explorer at shorter wavelengths. Comparing our z < 0.3luminosity density measurements with 0.2 < z < 1.2 fromClassifying Objects by Medium Band Observations in 17 Filters(COMBO-17), we find that the 280-nm density evolves asρL~ (1 +z)β with β= 2.1 +/- 0.2; andfind no evidence for any change in slope over this redshift range. Bycomparing with other measurements of cosmic star formation history, weestimate that the effective dust attenuation at 280nm has increased by0.8 +/- 0.3mag between z= 0 and 1.