Bibcode
Cristóbal-Hornillos, D.; Aguerri, J. A. L.; Moles, M.; Perea, J.; Castander, F. J.; Broadhurst, T.; Alfaro, E. J.; Benítez, N.; Cabrera-Caño, J.; Cepa, J.; Cerviño, M.; Fernández-Soto, A.; González Delgado, R. M.; Husillos, C.; Infante, L.; Márquez, I.; Martínez, V. J.; Masegosa, J.; del Olmo, A.; Prada, F.; Quintana, J. M.; Sánchez, S. F.
Bibliographical reference
The Astrophysical Journal, Volume 696, Issue 2, pp. 1554-1575 (2009).
Advertised on:
5
2009
Journal
Citations
42
Refereed citations
39
Description
The ALHAMBRA survey aims to cover 4 deg2 using a system of 20
contiguous, equal width, medium-band filters spanning the range 3500
Å-9700 Å plus the standard JHKs filters. Here we analyze
deep near-IR number counts of one of our fields (ALH08) for which we
have a relatively large area (0.5 deg2) and faint photometry
(J = 22.4, H = 21.3, and K = 20.0 at the 50% of recovery efficiency for
point-like sources). We find that the logarithmic gradient of the galaxy
counts undergoes a distinct change to a flatter slope in each band: from
0.44 at [17.0, 18.5] to 0.34 at [19.5, 22.0] for the J band; for the H
band 0.46 at [15.5, 18.0] to 0.36 at [19.0, 21.0], and in Ks the change
is from 0.53 in the range [15.0, 17.0] to 0.33 in the interval [18.0,
20.0]. These observations together with faint optical counts are used to
constrain models that include density and luminosity evolution of the
local type-dependent luminosity functions. Our models imply a decline in
the space density of evolved early-type galaxies with increasing
redshift, such that only 30%-50% of the bulk of the present day red
ellipticals was already in place at z ~ 1.
Based on observations collected at the German-Spanish Astronomical
Center, Calar Alto, jointly operated by the Max-Planck-Institut für
Astronomie Heidelberg and the Instituto de Astrofísica de
Andalucía (CSIC).
Related projects
Galaxy Evolution in Clusters of Galaxies
Galaxies in the universe can be located in different environments, some of them are isolated or in low density regions and they are usually called field galaxies. The others can be located in galaxy associations, going from loose groups to clusters or even superclusters of galaxies. One of the foremost challenges of the modern Astrophysics is to
Jairo
Méndez Abreu