... SIGMA assembly to GRANAT satellite is shown a href = granat _assembly.jpg here /a p The main results from SIGMA include the VERY deep (more than 5 billion seconds) imaging of the galactic center region, discovery of the electron-positron annihilation lines from the Galactic micro-quasar ...

Lack of co oling flow clusters at z 0.5 A. Vikhlinin1,2 , R. Burenin2 , W. R. Forman1 , C. Jones1 , A. Hornstrup3 , S. S. Murray1, and H. Quintana4 1 2 3 4 Harvard-Smithsonian ... Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile The goal of this work is to study the incidence rate of co oling flows in the high redshift clusters using Chandra observations of z 0.5 ob jects from a new large, ... Fig. ... Lack of "cooling flow" clusters at z > 0.5 3 Fig. ...