The radial velocity dispersion profile of the Galactic halo : constraining the density profile of the dark halo of the Milky Way
The radial velocity dispersion profile of the Galactic halo : constraining the density profile of the dark halo of the Milky Way
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DOI：
10.1111/j.1365-2966.2005.09367.x
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发表时间：
2005-06
影响因子：
4.8
通讯作者：
G. Battaglia;A. Helmi;H. Morrison;P. Harding;E. Olszewski;M. Mateo;K. Freeman;J. Norris;S. A. S
中科院分区：
文献类型：
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作者：
G. Battaglia;A. Helmi;H. Morrison;P. Harding;E. Olszewski;M. Mateo;K. Freeman;J. Norris;S. A. S
我们已经编制了一个新的样本，240晕对象的精确距离和径向速度测量，包括球状星团，卫星星系，现场蓝色水平分支（FHB）恒星和红巨星从意大利面条调查。新的数据导致银河系中心半径超过50千秒差距的已知物体数量显著增加，这使得可以可靠地确定非常大距离的径向速度分散分布。径向速度色散在30 kpc处几乎为120 km s −1，然后在120 kpc处持续下降到50 km s −1。这种下降对银河系暗物质晕的密度分布和总质量提出了重要的限制。对于常速度各向异性，等温剖面被排除，而对于常速度各向异性，
We have compiled a new sample of 240 halo objects with accurate distance and radial velocity measurements, including globular clusters, satellite galaxies, field blue horizontal branch (FHB) stars and red giant stars from the Spaghetti survey. The new data lead to a significant increase in the number of known objects for Galactocentric radii beyond 50 kpc, which allows a reliable determination of the radial velocity dispersion profile out to very large distances. The radial velocity dispersion shows an almost constant value of 120 km s −1 out to 30 kpc and then continuously declines down to 50 km s −1 at about 120 kpc. This fall-off puts important constraints on the density profile and total mass of the dark matter halo of the Milky Way. Fo ra constant velocity anisotropy, the isothermal profile is ruled out, while both a dark halo ∞