Abstract
We measure the two-point angular correlation function of a sample of
4289 223 galaxies with r <19.4 mag from the Sloan Digital Sky Survey
(SDSS) as a function of photometric redshift, absolute magnitude and
colour down to Mr - 5 log h = -14 mag. Photometric redshifts
are estimated from ugriz model magnitudes and two Petrosian radii using
the artificial neural network package ANNz, taking advantage of the
Galaxy And Mass Assembly (GAMA) spectroscopic sample as our training
set. These photometric redshifts are then used to determine absolute
magnitudes and colours. For all our samples, we estimate the underlying
redshift and absolute magnitude distributions using Monte Carlo
resampling. These redshift distributions are used in Limber's equation
to obtain spatial correlation function parameters from power-law fits to
the angular correlation function. We confirm an increase in clustering
strength for sub-L* red galaxies compared with ˜L* red galaxies at
small scales in all redshift bins, whereas for the blue population the
correlation length is almost independent of luminosity for ˜L*
galaxies and fainter. A linear relation between relative bias and log
luminosity is found to hold down to luminosities L ˜ 0.03L*. We
find that the redshift dependence of the bias of the L* population can
be described by the passive evolution model of Tegmark & Peebles. A
visual inspection of a random sample from our r <19.4 sample of SDSS
galaxies reveals that about 10 per cent are spurious, with a higher
contamination rate towards very faint absolute magnitudes due to
over-deblended nearby galaxies. We correct for this contamination in our
clustering analysis.
Original language | English |
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Pages (from-to) | 1527-1548 |
Number of pages | 22 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 425 |
Issue number | 2 |
DOIs | |
Publication status | Published - 11 Sep 2012 |