Bibcode
Domínguez-Palmero, L.; Balcells, M.; Prieto, M.; Cristóbal-Hornillos, D.; Erwin, P.; Eliche-Moral, C.
Bibliographical reference
II International GTC Workshop: Science with GTC 1st-light Instruments and the LMT (Eds. A. M. Hidalgo-Gámez, J. J. González, J. M. Rodríguez Espinosa, and S. Torres-Peimbert) Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) Vol. 24, pp. 233-234 (2005) (http://www.astroscu.unam.mx/~rmaa/)
Advertised on:
12
2005
Citations
0
Refereed citations
0
Description
We have studied the colors of the bulge component of 133 galaxies from
the HST Groth Strip Survey (Groth et al. 1994), covering redshifts 0.3
< z < 1.0. We selected all objects apparent radii R > 1.4'',
and inclination above 50 degrees in order to avoid reddening from dust
in the disk on one side of the bulges. We find that, as in the Local
Universe, the minor axis color profiles are negative (bluer outside),
and fairly gentle, indicating that bulge colors are not distinctly
different from disk colors. In most cases, dust bands are the most
important morphological structure in the color maps. In a subsample of
76 galaxies with spectroscopic redshifts, we analyze central rest-frame
colors using K-corrections. Bulge colors do not globally become bluer at
higher redshifts. This suggests that there were 'old' bulges at z = 0.8.
The color-magnitude distribution of intermediate-z bulges is steeper
than that of bulges in the Local Universe. The most massive bulges are
as red as local bulges, while the remainder are significantly bluer, a
possible sign of late bulge formation.