the distant 3cr radio-galaxies are amongst the most luminous objects in the universe and their nature and structure have been probed across a wide range of wavebands. the sources in this proposal are the most distant of the bright 3cr galaxies, all with redshifts near 1. while these galaxies are at cosmologically interesting distances they are not so distant that high signal-to-noise observations are impossible to obtain in reasonable times. the proposers are currently carrying out a programme of observations of these galaxies in the radio, submillimetre, near-infrared and optical/uv wavebands, using the vla, jcmt, ukirt and hst respectively. the key element of this work is the hst imaging: combined with high-resolution vla radio maps these images put us in a unique position to study both the origins of the radio emission in these sources, and its relation to the luminosity of the host galaxy, leading to the key goal of understanding the interactions between the radio source and the nuclear and star formation activity occurring. studying the structure of the 3cr galaxies in the radio and optical wavebands is of great importance; however, the absorption and re-emission of optical and ultraviolet radiation from both stellar and non-thermal sources by interstellar dust grains can have a major influence on the appearance of galaxies in the optical waveband. these galaxies imaged with the hst appear dramatically different in the blue hst images and the near- infrared images obtained using ground-based telescopes; many of the blue images have a highly irregular appearance while in the k-band the galaxies are elliptical in form. iso observations will allow us to determine the luminosity of the galaxies at far-infrared wavelengths and to investigate the mass and temperature of dust in these sources. if powerful star formation is occurring in these galaxies then a large, presently undetected fraction of their total luminosity... will be revealed by the proposed observations. only iso observations are capable of fully determining the far-infrared properties of these sources and completing our observational programme between the submillimetre and near- infrared wavebands.
Instrument
PHT22
Temporal Coverage
1997-04-10T10:49:30Z/1997-08-17T10:07:52Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
