On high proper motion white dwarfs from photographic surveys
On high proper motion white dwarfs from photographic surveys
复制标题
摄影调查中的高自行白矮星
DOI：
10.1051/0004-6361:20011296
复制
发表时间：
2001
影响因子：
6.5
通讯作者：
France.
中科院分区：
文献类型：
--
作者：
C. Reylé;A. Robin;M. Besançon;France Universite de Bretagne;Vannes;France.
奥本海默等人（[CITE]）对高自行白色矮星的解释引发了一场激烈的争论。虽然发现者将他们的大部分发现确定为暗晕成员，但其他人将相同的样本解释为基本上由盘星和/或厚盘星组成。我们使用“贝桑松”模型提供的银河系恒星种群的全面描述来产生奥本海默等人的真实模拟数据，包括所有观测选择和校准偏差。结论是明确的：由普通的局部密度和运动学假设得到的厚盘白色矮星足以解释观测到的天体，不需要晕白色矮星。这一结论对模型成分的合理变化是稳健的。误解的主要原因似乎是自行选择的星星样本的速度分布严重偏向于高速度。这在以前的分析中被忽略了。显然，这并不能证明像晕白色矮星这样的天体不存在，但是奥本海默等人的观测结果将它们在暗物质晕中的可能贡献降低到了极低的比例。
The interpretation of high proper motion white dwarfs detected by Oppenheimer et al. ([CITE]) was the start of a lively controversy. While the discoverers identify a large fraction of their findings as dark halo members, others interpret the same sample as essentially made of disc and/or thick disc stars. We use the comprehensive description of Galactic stellar populations provided by the "Besancon" model to produce a realistic simulation of Oppenheimer et al. data, including all observational selections and calibration biases. The conclusion is unambiguous: Thick disc white dwarfs resulting from ordinary hypotheses on the local density and kinematics are sufficient to explain the observed objects, there is no need for halo white dwarfs. This conclusion is robust to reasonable changes in model ingredients. The main cause of the misinterpretation seems to be that the velocity distribution of a proper motion selected star sample is severely biased in favour of high velocities. This has been neglected in previous analyses. Obviously this does not prove that no such objects like halo white dwarfs can exist, but Oppenheimer et al. observations drive their possible contribution in the dark matter halo down to an extremely low fraction.