TY - JOUR
T1 - The clustering and abundance of star-forming and passive galaxies at z ~ 2
AU - Hartley, W. G.
AU - Lane, K. P.
AU - Almaini, O.
AU - Cirasuolo, M.
AU - Foucaud, S.
AU - Simpson, C.
AU - Maddox, S.
AU - Smail, I.
AU - Conselice, C. J.
AU - McLure, R. J.
AU - Dunlop, James
PY - 2008/12/1
Y1 - 2008/12/1
N2 - We use the UKIRT (United Kingdom Infrared Telescope) Infrared Deep Sky
Survey (UKIDSS) Ultra-deep survey (UDS), currently the deepest panoramic
near-infrared survey, together with deep Subaru optical imaging to
measure the clustering, number counts and luminosity function of
galaxies at z ~ 2 selected using the BzK selection technique. We find
that both star-forming (sBzK) and passive (pBzK) galaxies, to a
magnitude limit of KAB <23, are strongly clustered. The
passive galaxies are the most strongly clustered population, with
scalelengths of r0 =
15.0+1.9-2.2h-1Mpc compared with
r0 = 6.75+0.34-0.37h-1Mpc
for star-forming galaxies. The direct implication is that passive
galaxies inhabit the most massive dark matter haloes, and are thus
identified as the progenitors of the most massive galaxies at the
present day. In addition, the pBzKs exhibit a sharp flattening and
potential turnover in their number counts, in agreement with other
recent studies. This plateau cannot be explained by the effects of
incompleteness. We conclude that only very massive galaxies are
undergoing passive evolution at this early epoch, consistent with the
downsizing scenario for galaxy evolution. Assuming a purely passive
evolution for the pBzKs from their median redshift to the present day,
their luminosity function suggests that only ~2.5 per cent of
present-day massive ellipticals had a pBzK as a main progenitor.
AB - We use the UKIRT (United Kingdom Infrared Telescope) Infrared Deep Sky
Survey (UKIDSS) Ultra-deep survey (UDS), currently the deepest panoramic
near-infrared survey, together with deep Subaru optical imaging to
measure the clustering, number counts and luminosity function of
galaxies at z ~ 2 selected using the BzK selection technique. We find
that both star-forming (sBzK) and passive (pBzK) galaxies, to a
magnitude limit of KAB <23, are strongly clustered. The
passive galaxies are the most strongly clustered population, with
scalelengths of r0 =
15.0+1.9-2.2h-1Mpc compared with
r0 = 6.75+0.34-0.37h-1Mpc
for star-forming galaxies. The direct implication is that passive
galaxies inhabit the most massive dark matter haloes, and are thus
identified as the progenitors of the most massive galaxies at the
present day. In addition, the pBzKs exhibit a sharp flattening and
potential turnover in their number counts, in agreement with other
recent studies. This plateau cannot be explained by the effects of
incompleteness. We conclude that only very massive galaxies are
undergoing passive evolution at this early epoch, consistent with the
downsizing scenario for galaxy evolution. Assuming a purely passive
evolution for the pBzKs from their median redshift to the present day,
their luminosity function suggests that only ~2.5 per cent of
present-day massive ellipticals had a pBzK as a main progenitor.
UR - http://www.scopus.com/inward/record.url?scp=57149136509&partnerID=8YFLogxK
U2 - 10.1111/j.1365-2966.2008.13956.x
DO - 10.1111/j.1365-2966.2008.13956.x
M3 - Article
VL - 391
SP - 1301
EP - 1307
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
ER -