Previous abstract Next abstract
Session 106 - Clusters of Galaxies.
Display session, Saturday, January 10
IRAS detected far-infrared (FIR) 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 10^44 to 10^45 ergs s^-1, 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 may be heated by collisions with hot cluster gas, which, if true, has the profound implication that FIR emission should be as important as X-ray emission for cooling the cores of these clusters. The IRAS observations lacked sufficient spatial resolution to determine whether the dust is distributed throughout the core of the cluster or concentrated in a particular location such as the central dominant galaxy.
We have employed ISOPHOT oversampled mapping techniques which allow for a spatial resolution of about 45\arcsec at 90 \mum in order to determine the location of the dust for the brightest of these clusters. In addition, some clusters were mapped in two or more filters to better constrain the temperature, and therefore the mass, of the dust. The location and mass of the dust constrains models of dust heating. Here we present ISOPHOT maps of the central five to six arcminutes (corresponding approximately to the central megaparsec) of the brightest FIR-luminous clusters of galaxies.
Program listing for Saturday