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    PR # 31552                                                                   
     We propose to observe with ASCA the A3921 cluster (z=0.094), for whic       
     h a previously obtained Rosat/PSPC pointing revealed specially intere       
     sting morphological properties. A group is probably falling on the ma       
     in  cluster. Moreover there is a surface brightness excess at the cen       
     ter, suggestive of the existence of a cooling flow. Our aims are to d       
     etermine the thermal properties of this cluster (kT distribution) in        
     order to understand better its dynamical state, and to derive reliabl       
     e estimates of its total mass, gas over total mass ratio and heavy el       
     ement mass. We will also be able to compare the shape of the distribu       
     tion of iron, gas and dark matter. For our purpose, ASCA spectro-imag       
     ing data (we will combine with previuosly spatial data obtained at be       
    tter spatial resolution) are e                                               
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