摘要:

AbstractThis article gives instructions for authors ofAstronomische Nachrichten(AN) how to prepare an article according to the current LATEX style. The source code of this paper may be used by the authors of AN as a template. For further information about the journal please look at the World Wide Web (URL http://www.aip.de:8080/∽astr_n/) where this text and accompanying style files can be obtained fro

ISSN:0004-6337    

DOI:10.1002/asna.2123190302

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractThe fifth Japaniese X‐ray astronomy satellite, Astro‐E, followingHakucho, Tenma, Ginga, andASCAis scheduled for launch in the year 2000 by the Institute of Space and Astronautical Science (ISAS) with an M‐V rocket. The satellite will be put into an approximately circular orbit with an altitude of ∽550 km and an inclination of ∽31°. There will be three experiments on board Astro‐E: an X‐ray micro‐calorimeter array, four X‐ray CCDs and a hard X‐ray detector. All three experiments combined, Astro‐E will become a spectrometer facility covering a wide energy band f

ISSN:0004-6337    

DOI:10.1002/asna.2123190303

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractNote from the editor: This article is a re‐print of the original, which appeared in Astron. Nachr. 319 (1/2), 7 (1998). In the original version the figure was ruined in the process of paper production and the scientific content of the paper considerably degraded. Instead of printing only the correct figure, thus loosing the scientific context, we decided to re‐print the whole article.We describe how recent X‐ray surveys have led to advances in the understanding of ultrasoft narrow‐line Seyfert 1 galaxies. The number of known ultrasoft narrow‐line Seyfert 1s has increased greatly in recent years due to X‐ray surveys, and it is now possible to obtian high quality 0.1–10 keV spectral and variability measurements for a large number of these galaxies. We generalize some of the correlations between X‐ray properties and optical emission line properties,focusing on how theROSATband spectral slope appears to be directly connected to the Boroson&Green (1992) primary eigenvector. We discuss how ultrasoft narrow‐line Seyfert 1s may well have extremal values of a primary physical parameter, and we describe new projects that should further improve our understanding of these extreme representatives of

ISSN:0004-6337    

DOI:10.1002/asna.2123190304

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractWe find a strong correlation between the effective radius of the largest early‐type galaxies in compact groups of galaxies and the velocity dispersion of the groups. The lack of a similar correlation for late type galaxies is supportive of the so called second generation merging scenario which predicts that ellipticals should dominate the internal dynamics of the groups, while late‐type galaxies are mainly recent interlopers which are still in an early stage of interaction with the group potent

ISSN:0004-6337    

DOI:10.1002/asna.2123190305

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2123190306

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractThe proper motions and stellar magnitudes for more than 20 000 stars distributed in areas around eight open clusters in the directions of the Sagittarius‐Carina and Perseus spiral arms were used to determine the cluster membership. Both spatial‐kinematical and statistical criteria were used for member seletion. The luminosity functions of cluster members were constructed and used for the further data improvement. The safest portions of the luminosity function free both from evolved stars and faint field star contamination were used for mass function construction. The composite mass function was derived from the data on five young clusters with logt<8.2. A dependence of the mass function slope on the adopted input parameters (mass‐luminosity relation and distance scale) and on member selection procedure was tested. The slope was found to vary in a range from 1.36 to 1.80 for lgM/M⊙ between 0.3 and 1.2. A possible relation between the individual MF slopes and cluster ages was indicated. The results are in good agreement with publish

ISSN:0004-6337    

DOI:10.1002/asna.2123190307

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2123190308

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractCCD photometry of possible standard stars, in Cousins B, V, R and I, in a field in the region of NGC 188 is presented.

ISSN:0004-6337    

DOI:10.1002/asna.2123190309

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2123190310

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractWe start with the hypotheses that the cluster space is limited by an ellipsoid with a semiprincipal axis directed to the observer and that the star density inside of concentric ellipsodal layers remains constant, although varying from layer to layer. It results that the mean star mass at the periphery of the cluster is 0.59 Sun masses smaller than that at the center.

ISSN:0004-6337    

DOI:10.1002/asna.2123190311

出版商:WILEY‐VCH Verlag    

年代:1998

数据来源: WILEY