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==> In this proposal, more time is being requested for CCOX.CLUSFIR
==> Time is to be transferred to this proposal from CCOX.CLUSFIR
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IRAS detected far-infrared emission typical of cool dust from the inner 100 to
200 kpc of 10% of rich clusters of galaxies. The FIR luminosities of these
clusters are 1E44 to 1E45 ergs/s, comparable to the entire blue luminosity of
the central cD galaxy and larger than the X-ray emission from the cluster core.
The dust that emits this FIR radiation is probably heated by collisions with
hot cluster gas, which has the profound implication that FIR emission should be
as important as X-ray emission for cooling the cores of these clusters. We
propose 60 to 180 um ISOPHOT mapping observations of Abell 1691 to determine
the origin of the dust (whether this material was stripped from galaxies or is
due to stellar mass loss in the cD) and the temperature and mass of the dust.