Search Publications

The HST Imaging Survey of BL Lac Objects

Urry, C. Megan; Scarpa, Riccardo; Treves, Aldo +2 more

Formation and Evolution of E and S0 Galaxies from HST and Keck Studies of z∼ 0.3-1 Clusters

Franx, Marijn; van Dokkum, Pieter; Kelson, Daniel +1 more

We have witnessed a dramatic increase over the last five years in results on distant galaxies, in large part because of the high resolution imaging capability of HST, and the multiobject spectroscopic capability of the Keck telescopes. Our program to obtain wide-field, multi-color WFPC2 mosaics with HST of intermediate redshift clusters, and spect…

Star Formation in the NICMOS HDF

Thompson, Rodger I.

This contribution discusses the rate of star formation in the galaxies observed in the NICMOS Hubble Deep Field. A combination of the earlier fluxes from the WFPC II HDF measurements and the NICMOS near infrared measurement produces a superb data base for the application of photometric redshift techniques. By capitalizing on the extended wavelengt…

Kinematics and Morphology of the Resolved Narrow Line Region in NGC 4151

Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +6 more

A complement of HST narrow band images, STIS slitless and long-slit spectra have been employed to probe the morphology, kinematics, dynamics, and ionization structure of the near-nuclear region in NGC 4151. The images illustrate the inner biconical cloud distribution which exhibits recessional velocities relative to the nucleus to the NE and appro…

The Morphological Evolution of Field Galaxies

Ellis, Richard S.

I review two observational programs which, together, promise to unravel the detailed astrophysical evolution of normal field galaxies over the last 5–7 Gyr. Systematic ground-based spectroscopy of faint galaxies have revealed an increasing faint end slope for the luminosity function with redshift. The trend is strongest for galaxies undergoing int…

Ultraluminous Infrared Galaxies: Far-Infrared Highlights

Clements, D. L.

We discuss two significant recent developments in the far-IRwith relevance to the study of Ultraluminous Infrared Galaxies(ULIRGs). The first of these is the discovery of an isotropiccosmological infrared background radiation (CIB). This has beendetected in observations by two different instruments (FIRAS (Puget etal. 1996, Hauser et al. 1998) and…

Metallicities of Nearby K-Dwarfs

Flynn, Chris; Kotoneva, Eira

The so-called ``G-dwarf problem'' emerged in the 1960's when it was noticed that the observed metal distribution of nearby stars differs from what is expected in simple models of the evolution of the Galaxy. We have determined metallicities for a sample of over 100 K dwarfs drawn from the Hipparcos catalog, using R-I colours to estimate effective …

A Survey for Hα emitting galaxies AT z ≃ 2.2

Oliva, E.; Moorwood, A. F. M.; Cuby, J. G. +1 more

The deepest survey for Hα emitting galaxies at z ≃ 2.2has recently been made in narrow-band (≃ 1%) filters around2.1µm using SOFI at the ESO NTT telescope. An effective area of≃ 100 sq. arcmin and a comoving volume of 9000 Mpc³ (forH₀ = 50, q₀ = 0.5) has been covered to a volume weighted 3σ line flux limit of…

Massive accretion disks

Scoville, N. Z.

Recent high resolution near infrared (HST-NICMOS) and mm-interferometric imaging have revealed dense gas and dust accretion disks in nearby ultra-luminous galactic nuclei. In the best studied ultraluminousIR galaxy, Arp 220, the 2µm imaging shows dust disks in both of the merging galactic nuclei and mm-CO line imaging indicates molecular gas…

Study of Early-Type Stars Populations and of Their Origin

Royer, F.