标题： NGC3532和NGC2287中白矮星的新详细检查 显示英文标题

标题： A new detailed examination of white dwarfs in NGC3532 and NGC2287

摘要： 我们呈现了对中等年龄的疏散星团NGC3532和NGC2287中的白矮星候选成员的光度和光谱研究结果。在调查的九个天体中，确定六个是这些星团的可能成员，其中四个在NGC3532，两个在NGC2287。对于这六个白矮星，我们利用它们的冷却时间估计值以及星团年龄来限制其前体恒星的寿命和质量。我们考察了这些天体在初始质量-最终质量空间中的位置，并发现它们现在不支持之前研究提出的初始质量-最终质量关系存在显著散射的证据。相反，我们证明当结合其他太阳金属丰度疏散星团的当前数据以及天狼星双星系统数据时，它们暗示了一个在初始质量范围3M$_{\odot}$$\simless$ M$_{\rm init}$$\simless$ 4M$_{\odot}$内比这个范围附近更低和更高的前体质量处更陡峭的IFMR。这种形式通常与恒星演化模型的预测一致，并且可以帮助人口合成模型再现白矮星质量分布中主峰高质端相对尖锐的下降现象。 显示英文摘要

摘要： We present the results of a photometric and spectroscopic study of the white dwarf candidate members of the intermediate age open clusters NGC3532 and NGC2287. Of the nine objects investigated, it is determined that six are probable members of the clusters, four in NGC3532 and two in NGC2287. For these six white dwarfs we use our estimates of their cooling times together with the cluster ages to constrain the lifetimes and masses of their progenitor stars. We examine the location of these objects in initial mass-final mass space and find that they now provide no evidence for substantial scatter in initial mass-final mass relation as suggested by previous investigations. Instead, we demonstrate that, when combined with current data from other solar metalicity open clusters and the Sirius binary system, they hint at an IFMR that is steeper in the initial mass range 3M$_{\odot}$$\simless$M$_{\rm init}$$\simless$4M$_{\odot}$ than at progenitor masses immediately lower and higher than this. This form is generally consistent with the predictions of stellar evolutionary models and can aid population synthesis models in reproducing the relatively sharp drop observed at the high mass end of the main peak in the mass distribution of white dwarfs.