期刊
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
卷 434, 期 4, 页码 2971-2981出版社
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stt1217
关键词
Galaxy: evolution; Galaxy: formation; Galaxy: halo; Galaxy: kinematics and dynamics; Galaxy: structure; galaxies: haloes
资金
- European Regional Development Fund [ERDF-080]
- ESF Research Networking Programme [2442]
- STFC [ST/J001341/1]
- Marie Curie Career Integration Grant
- NSF [AST-0908346]
- University of Michigan
- Direct For Mathematical & Physical Scien [0908346] Funding Source: National Science Foundation
- Division Of Astronomical Sciences [0908346] Funding Source: National Science Foundation
- Science and Technology Facilities Council [ST/J001341/1] Funding Source: researchfish
- STFC [ST/J001341/1] Funding Source: UKRI
Models of the Sagittarius stream have consistently found that the Milky Way disc is oriented such that its short axis is along the intermediate axis of the triaxial dark matter halo. We attempt to build models of disc galaxies in such an 'intermediate-axis orientation'. We do this with three models. In the first two cases we simply rigidly grow a disc in a triaxial halo such that the disc ends up perpendicular to the global intermediate axis. We also attempt to coax a disc to form in an intermediate-axis orientation by producing a gas+dark matter triaxial system with gas angular momentum about the intermediate axis. In all cases we fail to produce systems which remain with stellar angular momentum aligned with the halo's intermediate axis, even when the disc's potential flattens the inner halo such that the disc is everywhere perpendicular to the halo's local minor axis. For one of these unstable simulations we show that the potential is even rounder than the models of the Milky Way potential in the region probed by the Sagittarius stream. We conclude that the Milky Way's disc is very unlikely to be in an intermediate-axis orientation. However we find that a disc can persist off one of the principal planes of the potential. We propose that the disc of the Milky Way must be tilted relative to the principal axes of the dark matter halo. Direct confirmation of this prediction would constitute a critical test of Modified Newtonian Dynamics.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据