COSPATIAL COUNTERROTATING STELLAR DISKS IN THE VIRGO E7/S0 GALAXY NGC-4550

被引：179

作者：

RUBIN, VC ^{[1
]}

GRAHAM, JA ^{[1
]}

KENNEY, JDP ^{[1
]}

机构：

[1] YALE UNIV,DEPT ASTRON,NEW HAVEN,CT 06511

来源：

ASTROPHYSICAL JOURNAL | 1992年 / 394卷 / 01期

关键词：

GALAXIES; CLUSTERING; ELLIPTIC AND LENTICULAR; CD; KINEMATICS AND DYNAMICS;

D O I：

10.1086/186460

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We have discovered two cospatial stellar disks, one orbiting prograde, one orbiting retrograde, in NGC 4550, an E7/S0 galaxy in the core of the Virgo Cluster. One of the stellar disks is coincident with a gas disk. Absorption and emission-line velocities for the two counterrotating components have been measured over about one-third of the optical diameter (30"). We propose that after the initial stellar disk of NGC 4550 was formed, a substantial amount of counterrotating gas was acquired greater-than-or-equal-to 10(9) yr ago. It then settled to the plane via dissipation; the bulk of the counterrotating stars most likely for-med after the gas settled to the plane.

引用

页码：L9 / &

共 24 条

[1] THE 2-STREAM INSTABILITY IN INFINITE HOMOGENEOUS AND UNIFORMLY ROTATING STELLAR-SYSTEMS [J].