摘要:

AbstractThe differences between optical and X‐ray structures of galaxy clusters are discussed. We analyse in detail 7 Abell clusters. There is an increasing number of arguments in favour of different distributions of galaxies, gas, and dark matter in many clusters. We argue that most clusters present sub‐structures at least in the gaseous and galactic components and, moreover, the subclustering of different components does not always coincide. Such arguments strongly support the idea that most galaxy clusters are by far more complex systems than accepted until now and are usually not in an hydrostatic isothermal equilibr

ISSN:0004-6337    

DOI:10.1002/asna.2113170202

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113170203

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractIn this paper the definitions and properties of a newly dedicated set of high‐frequency filters based on smoothing‐and‐clipping are briefly described. New applications for the reduction of wide‐field 2048x2048 CCD spectral and direct images of a new deep survey KISS are also pr

ISSN:0004-6337    

DOI:10.1002/asna.2113170204

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractIt has been shown that the radio emission properties of spiral galaxies, if the other conditions are the same, are determined rather by the presence of the close neighbours than by space density of galaxies around them. The rate of occurence of radio sources and their radio luminosities among the spiral members of groups of galaxies depend on the projected seperation between them and their nearest neighbour. The shorter this seperation the higher the probability of radio emission.

ISSN:0004-6337    

DOI:10.1002/asna.2113170205

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113170207

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractIt is shown that gravitational theory allows stable equilibrium configurations of the degenerated Fermi gas, whose massesM≫M⊙and sizes are less than α = 2GM/c. They have no events horizon at the distancer= α from the center. Orbits of test particles near the above objects are consi

ISSN:0004-6337    

DOI:10.1002/asna.2113170208

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractA study of the structure and kinematics of the Galaxy from Tautenburg Schmidt plates taken towards the Galactic centre (l= 17.0°,b= +0.8°) is presented. Proper motions andB, Vmagnitudes were determined for about 36 500 stars up to the limiting magnitudeV= 16m.8 in a field of 8.95 square degrees. Proper motion accuracy of about 3 mas/year has been obtained for stars brighter thanV= 15m. The rms errors of stellar magnitudes and (B–V) colours is about 0.1 mag.The majority of field stars in the survey are main sequence stars and red giants of the disk. They belong to the Local or Sagittarius‐Carina arms, or they are located between these spiral arms. Comparing the modelled and observed distributions of magnitudes and colours, we specified the interstellar extinction determined in the preceding study of open clusters in this field.The luminosity function towards the Galactic centre was determined for stars with absolute magnitudes from ‐4m.35 to +9m. Kinematical and spatial distribution parameters up to 4 kpc from the Sun were obtained as a function of galactocentric d

ISSN:0004-6337    

DOI:10.1002/asna.2113170209

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractFinding charts and photoelectric magnitudes of stars in theUBVRsystem in 26 fields of the MEGA programme are presented. This part of the photometric survey near the Main Galactic Meridian includes the fields with right ascentions 8h<α<16h30mand declinations −2°<δ<58°. Together with the finding charts of 2.5° × 2.5° the equatorial coordinates of the stars are given for epoch and equinox 1950. Photometric properties of the night sky at the Mount Terskol observatory near Mount Elbrus are derived from the photoelectric obse

ISSN:0004-6337    

DOI:10.1002/asna.2113170210

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113170212

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractNine positions of comet Hale‐Bopp (1995 O1), derived from theX‐Ypositions on Bosscha Schmidt plates, taken between August 15 to August 22, 1995, are gi

ISSN:0004-6337    

DOI:10.1002/asna.2113170213

出版商:WILEY‐VCH Verlag    

年代:1996

数据来源: WILEY