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==> In this proposal, more time is being requested for GMILEY.DUSTHZRG
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Radio-loud active galactic nuclei (AGNs) are unique probes of the universe,
that can be observed out to large distances without bias with respect to
optical or infrared properties. The best studied sample of such objects is
the 3CR catalog. We are carrying out a WFPC2 snapshot imaging survey with HST
and have secured excellent data for almost the entire 3CR catalog. A crucial
result is the ubiquity of dust-lane galaxies, strongly reminiscent of Cen A,
and galaxies with chaotic dust distributions and/or disturbed morphologies.
These features are readily identified out to redshift 0.5. Here we propose to
expand our programme GMILEY.DUSTHZRG to obtain CAM 15 micron images of all
58 3CR galaxies at redshift less than 0.5 that are visible for more than 25
percent of the rest of the ISO mission. The ISO data will highlight the
ubiquity, role and importance of starbursts in 3CR galaxies, will elucidate
the relation between various classes of AGNs, will allow tracing of
evolutionary effects, will provide a low-z reference point for our ongoing
high-z measurements, and will reveal dust emission from the brighests members
of clusters in which the 3CR galaxies tend to be located.