UVES observations of the Canis Major overdensity
UVES observations of the Canis Major overdensity
复制标题
大犬座超密度的 UVES 观测
DOI：
10.1051/0004-6361:200400118
复制
发表时间：
2004
影响因子：
6.5
通讯作者：
R. Buonanno
中科院分区：
文献类型：
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作者：
L. Sbordone;P. Bonifacio;G. Marconi;S. Zaggia;R. Buonanno
我们提出了第一个详细的化学丰度的三个巨大的恒星，这是候选成员的大犬座超密度，通过使用FLAMES-UVES在VLT。在疏散星团NGC 2477的背景下，这些恒星的径向速度与该结构的成员资格相一致。然而，由于星系盘的污染，径向速度本身无法确定成员资格。金属丰度跨越小于或类似于[Fe/H]小于或类似于+0.1的范围-0.5。假设这三颗恒星中至少有一颗确实是CMa的成员，这意味着这个结构经历了高水平的化学处理，可以与银河系圆盘相媲美。其中最富金属的星星EIS 6631显示出与银河系恒星明显不同的几个丰度比：[α/Fe]接近于-0.2，[Cu/Fe]接近于+0.25，[La/Fe]接近于+0.6，[Ce/Fe]接近于+0.8，[Nd/Fe]接近于+0.6。这些比率表明这颗星星很可能是在外部星系中形成的。
We present the first detailed chemical abundances for three giant stars which are candidate members of the Canis Major overdensity, obtained by using FLAMES-UVES at VLT. The stars, in the background of the open cluster NGC 2477, have radial velocities compatible with a membership to this structure. However, due to Galactic disc contamination, radial velocity by itself is unable to firmly establish membership. The metallicities span the range -0.5 less than or similar to [Fe/H] less than or similar to +0.1. Assuming that at least one of the three stars is indeed a member of CMa implies that this structure has undergone a high level of chemical processing, comparable to that of the Galactic disc. The most metal-rich star of the sample, EIS 6631, displays several abundance ratios which are remarkably different from those of Galactic stars: [alpha/Fe] similar to -0.2, [Cu/Fe] similar to +0.25, [La/Fe] similar to +0.6, [Ce/Fe] similar to +0.8 and [Nd/Fe] similar to +0.6. These ratios make it likely that this star was formed in an external galaxy.
银河系及其卫星中恒星的化学丰度和混合
DOI：
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发表时间：
2004
期刊：
研究会集録(ESO-ARCETRI WORKSHOP, Sept.2004, Italy)
影响因子：
--
作者：
Minowa;Y.;Kobayashi;N.;他3名とすばるチーム;Takuji Tsujimoto
通讯作者：
Takuji Tsujimoto