Showing papers by "Peter Eisenhardt published in 1995"
TL;DR: In this paper, a wide-field optical and near-IR (JHK) imaging is presented for two rich galaxy clusters: Abell~370 at 0.374 and Abell ~851 (Cl0939+47), where the colors of the E/S0s are bluer than those in the Bower et al. (1992) Coma sample in the optical-K$ color.
Abstract: Wide-field optical and near--IR ($JHK$) imaging is presented for two rich galaxy clusters: Abell~370 at $z=0.374$ and Abell~851 (Cl0939+47) at $z=0.407$. Galaxy catalogs selected from the near--IR images are 90\% complete to approximately 1.5 mag below $K^\ast$ resulting in samples with $\sim$100 probable member galaxies per cluster in the central $\sim$2 Mpc. Comparison with $HST$ WFPC images yields subsamples of $\sim$70 galaxies in each cluster with morphological types. Analysis of the complete samples and the $HST$ subsamples shows that the $z\sim 0.4$ E/S0s are bluer than those in the Bower et al.\ (1992) Coma sample in the optical$-K$ color by $0.13$~mag for Abell~370 and by $0.18$~mag for Abell~851. If real, the bluing of the E/S0 populations at moderate redshift is consistent with that calculated from the Bruzual and Charlot (1993) models of passive elliptical galaxy evolution. In both clusters the intrinsic scatter of the known E/S0s about their optical$-K$ color--mag relation is small ($\sim 0.06$ mag) and not significantly different from that of Coma E/S0s as given by Bower et al.\ (1992), indicating that the galaxies within each cluster formed at the same time at an early epoch.
125 citations
TL;DR: In this paper, a wide-field optical and near-IR (JHK) imaging is presented for two rich galaxy clusters: Abell~370 at 0.374 and Abell ~851 (Cl0939+47), where the intrinsic scatter of the known E/S0s about their optical-K$ color-mag relation is small.
Abstract: Wide-field optical and near--IR ($JHK$) imaging is presented for two rich galaxy clusters: Abell~370 at $z=0.374$ and Abell~851 (Cl0939+47) at $z=0.407$. Galaxy catalogs selected from the near--IR images are 90\\% complete to approximately 1.5 mag below $K^\\ast$ resulting in samples with $\\sim$100 probable member galaxies per cluster in the central $\\sim$2 Mpc. Comparison with $HST$ WFPC images yields subsamples of $\\sim$70 galaxies in each cluster with morphological types. Analysis of the complete samples and the $HST$ subsamples shows that the $z\\sim 0.4$ E/S0s are bluer than those in the Bower et al.\\ (1992) Coma sample in the optical$-K$ color by $0.13$~mag for Abell~370 and by $0.18$~mag for Abell~851. If real, the bluing of the E/S0 populations at moderate redshift is consistent with that calculated from the Bruzual and Charlot (1993) models of passive elliptical galaxy evolution. In both clusters the intrinsic scatter of the known E/S0s about their optical$-K$ color--mag relation is small ($\\sim 0.06$ mag) and not significantly different from that of Coma E/S0s as given by Bower et al.\\ (1992), indicating that the galaxies within each cluster formed at the same time at an early epoch.
119 citations
01 Jan 1995
TL;DR: The Kuiper Airborne Observatory has been a powerful instrument for the study of nearby galaxies, and SOFIA could probe still further into the local Universe as mentioned in this paper, however, a comprehensive program of extragalactic exploration in the infrared - and in particular a study of galaxies at cosmological redshifts - requires the high sensitivity and complete wavelength coverage which is achievable only with a cryogenic telescope in space.
Abstract: The Kuiper Airborne Observatory has been a powerful instrument for the study of nearby galaxies, and SOFIA could probe still further into the local Universe. However, a comprehensive program of extragalactic exploration in the infrared - and in particular a study of galaxies at cosmological redshifts - requires the high sensitivity and complete wavelength coverage which is achievable only with a cryogenic telescope in space. This program was begun by IRAS and will be continued by the upcoming ISO (Infrared Space Observatory), WIRE (Wide field Infrared Explorer) and SIRTF (Space Infrared Telescope Facility) missions. This paper previews a set of extragalactic investigations which could be carried out by these missions.
1 citations