A COLD MILKY WAY STELLAR STREAM IN THE DIRECTION OF TRIANGULUM
A COLD MILKY WAY STELLAR STREAM IN THE DIRECTION OF TRIANGULUM
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DOI：
10.1088/2041-8205/760/1/l6
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发表时间：
2012-09
期刊：
影响因子：
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通讯作者：
A. Bonaca;M. Geha;N. Kallivayalil
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文献类型：
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作者：
A. Bonaca;M. Geha;N. Kallivayalil
我们提供了仙女座星系和三角星系（M31 和 M33）方向上新的银河系恒星潮汐流的证据。使用匹配滤波器技术，我们通过创建恒星密度图来搜索斯隆数字巡天数据第 8 版，该图探测距离在 8 到 40 kpc 之间的银河系晕。对这些地图的目视搜索可恢复所有已知的主要恒星流，以及 M31/M33 方向的新流，我们将其命名为三角流。流在天空上的跨度为 0.°2 x 12°，或物理单位为 75 pc x 5.5 kpc，最佳拟合距离为 26 ± 4 kpc。溪流的宽度与球状星团的潮汐遗迹一致。流域的颜色-星等图显示了密度过高，如果将其确定为主序岔路，则对应于古老的（∼12 Gyr）和贫金属（[Fe/H] ∼−1.0 dex）恒星群。未来对该冷流和类似冷流的运动学研究将为银河系引力势的形状提供严格的限制。
We present evidence for a new Milky Way stellar tidal stream in the direction of the Andromeda and Triangulum (M31 and M33) galaxies. Using a matched-filter technique, we search the Sloan Digital Sky Survey Data Release 8 by creating stellar density maps which probe the Milky Way halo at distances between 8 and 40 kpc. A visual search of these maps recovers all of the major known stellar streams, as well as a new stream in the direction of M31/M33 that we name the Triangulum stream. The stream spans 0.°2 by 12° on the sky, or 75 pc by 5.5 kpc in physical units with a best-fitting distance of 26 ± 4 kpc. The width of the stream is consistent with being the tidal remnant of a globular cluster. A color–magnitude diagram of the stream region shows an overdensity which, if identified as a main-sequence turnoff, corresponds to an old (∼12 Gyr) and metal-poor ([Fe/H] ∼−1.0 dex) stellar population. Future kinematic studies of this and similar cold streams will provide tight constraints on the shape of the Galactic gravitational potential.