X-ray imaging of cooling flows

One of the implications of detailed modeling of X-ray observations of cooling flow clusters is that the intracluster medium in the cooling Bows must be inhomogeneous and have multi-temperature structure. While spectroscopic results have provided some support for a multi-temperature structure in the cooling flow regions, we have not yet observed directly the inhomogeneous structure in high resolution cluster images. Observations of both, the size and amplitude distribution of the inhomogeneities and the temperature distribution of the gas would be very important in providing input parameters for a more detailed and realistic modeling of cooling flow structure. In this review the search for inhomogeneities in cooling flows and some spectral evidence for the multi-temperature structure of cooling flows are discussed for the examples of the X-ray halo of M87 and ROSAT - ASCA observations of A2390, respectively. A simple model of cooling flows in an inhomogeneous intracluster medium is presented and the implications of the inhomogeneous structure for the cluster mass and gas mass determination and for the measurement of the Sunyaev-Zel'dovich effect are discussed.