arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节（Veterans Day），12 日无更新
arXiv 1404.7441astro-ph.SR
收藏

麦哲伦星云中沃尔夫-拉叶星的现代搜寻：初步结果

A Modern Search for Wolf-Rayet Stars in the Magellanic Clouds: First Results

Philip Massey, Kathryn F. Neugent, Nidia Morrell, D. John Hillier

备注：
Astrophysical Journal, in press
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

多年来，定向巡天和附带光谱学已经在SMC中识别出12颗沃尔夫-拉叶星（WR），在LMC中识别出139颗，这些数字通常被描述为"基本上完整的"。“然而，几乎每年都会在LMC中发现新的WR。因此，我们已经开始了一个新的调查麦哲伦云使用相同的干涉滤波器成像技术以前适用于M31和M33。我们报告我们的第一个观测季节，我们已经成功地调查了我们的SMC和LMC的预期面积的~15 $%。光谱学已经证实了9个新发现的WRs在LMC（增加6%），包括一个WO型，只有第三个已知的星系和第二个最近被发现。另外八颗是包含吸收成分的WN3恒星。其中两颗的吸收很可能来自O型伴星，但其他六颗都很不寻常。五颗星会被天真地归类为"WN 3 + O3 V"，但这样的配对是不太可能的，因为O3星的稀有性，这个阶段的持续时间很短（这与WN星的伴星的演化不相称），而且这些恒星比O3 V星要暗得多。第六颗星也可能属于这一类。CMFGEN模型表明，这些恒星是热的，热发光的，像其他WN3恒星一样富含N，但缺乏WNs所特有的强风。最后，我们讨论两个罕见的？p星和4颗超巨星，并提出HD 38489可能有WN伴星。

英文摘要：

Over the years, directed surveys and incidental spectroscopy have identified 12 Wolf-Rayet (WR) stars in the SMC and 139 in the LMC, numbers which are often described as "essentially} complete." Yet, new WRs are discovered in the LMC almost yearly. We have therefore initiated a new survey of both Magellanic Clouds using the same interference-filter imaging technique previously applied to M31 and M33. We report on our first observing season, in which we have successfully surveyed ~15$% of our intended area of the SMC and LMC. Spectroscopy has confirmed 9 newly found WRs in the LMC (a 6% increase), including one of WO-type, only the third known in that galaxy and the second to be discovered recently. The other eight are WN3 stars that include an absorption component. In two, the absorption is likely from an O-type companion, but the other six are quite unusual. Five would be classified naively as "WN3+O3 V," but such a pairing is unlikely given the rarity of O3 stars, the short duration of this phase (which is incommensurate with the evolution of a companion to a WN star), and because these stars are considerably fainter than O3 V stars. The sixth star may also fall into this category. CMFGEN modeling suggests these stars are hot, bolometrically luminous, and N-rich like other WN3 stars, but lack the strong winds that characterize WNs. Finally, we discuss two rare Of?p stars and four Of supergiants we found, and propose that the B[e] star HD 38489 may have a WN companion.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑