RTT150 . ... This optical scheme is similar to 1:7.7 system but has the different parameters of secondary mirror 2 and corrector 3. Primary mirror 1 reflects light to the secondary mirror 2 which collects it on the focal surface of system. Lens corrector 3 is placed between focal surface and the secondary mirror which allows to obtain large flat linear field of 100 mm diameter. Focal length, mm . ... Linear field of view, mm . ... Angular field of view . ... 0.039 mm, %, at least . ...

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. ...