we will use the sws, lws, and isophot instruments to determine the nature of the cold material in cooling flow clusters of galaxies. x-ray spectra indicate that very large fluxes of soft x-rays are being absorbed by some cold component of the intracluster medium. the x-ray absorbing cold material may have a mass of 10e11-10e12 msun and thus be the ultimate repository of the cooling flow. yet, this cold component has yet to be identified or verified by observations in any other spectral band. in particular, the energy absorbed as x-ray. about 3x10^43 erg/s, must re-emerge in another spectral band, and this cooling emission from the cold gas has yet to be observed. the best present models indicate that the cold gas must primarily emit in the fir. if the gas is relatively dust-free, the primary emission should be in lines of c i, c ii, o i, and si ii. if the cold material is very dusty, the bulk of the emission might be dust radiated fir continuum. we will compare the rosat and asca spatially resolved x-ray spectra from the clusters with spatially resolved fir spectra in c ii (158 mu), o i (63 mu), and si ii (35 mu),and broad-band photometry from 60 to 200 microns. either we will strongly detect this emission, or the existence of this cold gas will be placed in great doubt. assuming we do detect the emission, this data will allow us to determine the density, temperature and total mass of the absorbing gas, and the role of dust in the x-ray absorption and energetics of the cool gas. by looking at a sample of 10 clusters, we can determine the relationship of this cold gas to the x-ray emitting hot gas, the overall properties of the clusters, and the properties of the central galaxy and its nuclear activity.
Instrument
LWS02 , PHT32 , SWS02
Temporal Coverage
1996-08-21T00:03:56Z/1998-02-01T22:26:44Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds 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.
European Space Agency, JAFFE et al., 1999, 'COOL GAS AND DUST IN COOLING FLOWS IN CLUSTERS OF GALAXIES', 1.0, European Space Agency, https://doi.org/10.5270/esa-5xnibf0
