On the apparent lack of be x-ray binaries with black holes in the galaxy and in the Magellanic clouds
Janusz Ziolkowski, Krzysztof Belczynski
备注：
An updated version of the review paper to be published in "Frontier Objects in Astrophysics and Particle Physics" (Procs. of the Vulcano Workshop 2010), eds. F. Giovannelli and G. Mannocchi, Bologna, Italy, 2011
在银河系和麦哲伦星云中，迄今已知有170颗Be X射线双星。其中，111颗拥有一颗中子星，提醒一下，伴星的性质尚不清楚。到目前为止，还没有发现黑洞。这种差异被称为一个失踪的Be -黑洞X射线二元问题。在银河系中形成Be X射线双星之后的恒星星族合成计算（Belczynski and Ziolkowski 2009）表明，银河系中不存在Be+BH X射线双星缺失的问题（Be -黑洞X射线双星的预期数量为0到2，这与观测到的银河系样本完全一致）。然而，对麦哲伦云的初步计算表明，有一个问题，即缺少的Be+BH X射线双星的云（预期的数量约为6，而没有观察到）。我们相信，为了消除这种差异，我们必须考虑到麦哲伦星云中恒星形成速率与银河系不同的历史。目前正在进行新的恒星星族合成计算。一个更新的（截至2011年11月）名单，所有170 Be X射线双星已知目前在银河系和麦哲伦云包括在内。
英文摘要：
In the Galaxy and in the Magellanic Clouds there are 170 Be X-ray binaries known to-date. Out of those, 111 host a neutron star, and for the reminder the nature of a companion is not known. None, so far, is known to host a black hole. This disparity is referred to as a missing Be -- black hole X-ray binary problem. The stellar population synthesis calculations following the formation of Be X-ray binaries in the Galaxy (Belczynski and Ziolkowski 2009) demonstrate that there is no problem of the missing Be+BH X-ray binaries for the Galaxy (the expected number of Be -- black hole X-ray binaries is 0 to 2, which is entirely consistent with the observed Galactic sample). However, the preliminary calculations for Magellanic Clouds indicate that there is a problem of the missing Be+BH X-ray binaries for the Clouds (the expected number is about 6, while none is observed). We believe, that to remove the discrepancy, one has to take into account a different history of the star formation rate in the Magellanic Clouds, with the respect to the Galaxy. New stellar population synthesis calculations are currently being carried out. An updated (as of November 2011) list of all 170 Be X-ray binaries known presently in the Galaxy and in the Magellanic Clouds is included.
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Università Degli Studi di Padova（帕多瓦大学）；Istituto Nazionale di Astrofisica - Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）；Australian National University（澳大利亚国立大学）；NSF’s NOIRLab（美国国家科学基金会NOIR实验室）
The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. X. Enigmatic Class of Double Periodic Variables in the Large Magellanic Cloud
Massive WR stars are evolved massive stars characterized by strong mass-loss. Hypothetically, they can form either as single stars or as mass donors in close binaries. About 40% of the known WR stars are confirmed binaries, raising the question as to the impact of binarity on the WR population. By performing a spectral analysis of all multiple WR systems in the SMC, we obtain the full set of stellar parameters for each individual component. Mass-luminosity relations are tested, and the importance of the binary evolution channel is assessed. The spectral analysis is performed with the PoWR mode…
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Instituto de Astrofísica de Canarias（加那利群岛天体物理研究所）；Universidad de La Laguna（拉古纳大学）；Columbia University（哥伦比亚大学）；Lund University（隆德大学）；Nicolaus Copernicus University（尼古拉·哥白尼大学）；University of Arizona（亚利桑那大学）；Argelander Institut für Astronomie（阿尔兰德天文学研究所）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）
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Universität Heidelberg（海德堡大学）；University of Cambridge（剑桥大学）；University of Padova（帕多瓦大学）；Gran Sasso Science Institute (GSSI)（格兰萨索科学研究所）；INFN, Sezione di Padova（意大利国家核物理研究所帕多瓦分部）；University of Amsterdam（阿姆斯特丹大学）；Universitat de Barcelona (UB)（巴塞罗那大学）
Runaway OB stars are ejected from their parent clusters via two mechanisms, both involving multiple stars: the dynamical ejection scenario (DES) and the binary supernova scenario (BSS). We constrain the relative contributions from these two ejection mechanisms in the Small Magellanic Cloud (SMC) using data for 304 field OB stars from the spatially complete, Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4). We obtain stellar masses and projected rotational velocities $v_r\sin i $ for the sample using RIOTS4 spectra, and use transverse velocities $v_{\rm loc}$ from $\it…
Populations of evolved massive binary stars in the Small Magellanic Cloud II: Predictions from rapid binary evolution
Universität Bonn（波恩大学）；Argelander-Institut für Astronomie, Universität Bonn（波恩大学阿戈兰德尔天文研究所）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Instituto de Astrofísica de Canarias（加那利天体物理研究所）；Universidad de La Laguna（拉古纳大学）；Université de Genève（日内瓦大学）；Gravitational Wave Science Center (GWSC), Université de Genève（日内瓦大学引力波科学中心）；Foundation for Research & Technology Hellas (FORTH)（希腊研究与技术基金会）；Max-Planck-Institut für Extraterrestrische Physik（马克斯·普朗克地外物理研究所）
The population of young stars near the Supermassive black hole (SMBH) in the Galactic Center (GC) has presented an unexpected challenge to theories of star formation. Kinematics measurements of these stars have revealed a stellar disk structure (with an apparent 20% disk membership) that has provided important clues to the origin of these mysterious young stars. However many of the apparent disk properties are difficult to explain, including the low disk membership fraction and the high eccentricities, given the youth of this population. Thus far, all efforts to derive the properties of this d…
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2dF-AAOmega spectroscopy of massive stars in the Magellanic Clouds: The north-eastern region of the Large Magellanic Cloud
我们目前的光谱分类从光学光谱的263个大质量恒星在东北地区的大麦云云。观测到的2度场包括巨大的剑鱼座30恒星形成区，SN 1987 A的周围地区，以及剑鱼座30以南的一些恒星形成复合体。这是大多数恒星（203颗）的第一次分类，包括11颗双线分光双星。该样品还包括早期OC型光谱的第一个例子（AAOmega 30 Dor 248和280），其氮光谱的弱点和C IV 4658发射区分。我们建议，这些恒星有相对未加工的CNO丰度相比，形态正常的O型恒星，指示一个较早的演化阶段。通过对连续两个晚上观测结果的分析，我们对233颗恒星的径向速度进行了估计，发现了一个明显的单线双星和9个（> 3 sigma）与系统速度相比的异常值;后者可能是逃逸星或大振幅双星系统，需要进一步的光谱学来研究它们的性质。
The binary fraction of unevolved massive stars is thought to be 70-100% but there are few observational constraints on the binary fraction of the evolved version of a subset of these stars, the red supergiants (RSGs). Here we identify a complete sample of RSGs in the Large Magellanic Cloud (LMC) using new spectroscopic observations and archival UV, IR and broadband optical photometry. We find 4090 RSGs with log L/Lo > 3.5 with 1820 of them having log L/Lo > 4, which we believe is our completeness limit. We additionally spectroscopically confirmed 38 new RSG+B star binaries in the LMC, bringing…
