arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0905.0154astro-ph.SRastro-ph.IM
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用长基线光学干涉术对CI Cam周围的非对称尘埃壳成像

Imaging the asymmetric dust shell around CI Cam with long baseline optical interferometry

N. D. Thureau, J. D. Monnier, W. A. Traub, R. Millan-Gabet, E. Pedretti, J. -P. Berger, M. R. Garcia, F. P. Schloerb, A. -K. Tannirkulam

摘要:

我们提出了第一个高角分辨率观测B[e]星/X射线瞬态对象CI凸轮,进行了双望远镜红外光学望远镜阵列(IOTA),其升级的三望远镜版本(IOTA 3 T)和帕洛玛试验台干涉仪(PTI)。使用IONIC-3集成光学光束组合器获得了振动和闭合相位。CI Cam是在近红外H和K光谱波段观测到的,这些波长非常适合测量CI Cam周围热尘埃的大小和研究其几何形状。对1998年沙尘暴爆发后至2006年8年间沙尘暴能见度资料的分析表明,沙尘暴爆发后沙尘暴的能见度没有发生明显的变化。可见度数据显示CI Cam被拉长,这证实了星周环境的圆盘形状,并完全排除了球形尘埃壳的假设。封闭阶段的测量显示直接证据的不对称性,在拱星环境中的CI凸轮,我们得出结论,CI凸轮周围的尘埃在于在一个角度看到的不均匀的光盘。近红外尘埃辐射呈现椭圆形的倾斜高斯环,长轴a = 7.58 ± 0.24mas,轴比r = 0.39 ± 0.03,位置角θ = 35 ± 2 °。

英文摘要:

We present the first high angular resolution observation of the B[e] star/X-ray transient object CI Cam, performed with the two-telescope Infrared Optical Telescope Array (IOTA), its upgraded three-telescope version (IOTA3T) and the Palomar Testbed Interferometer (PTI). Visibilities and closure phases were obtained using the IONIC-3 integrated optics beam combiner. CI Cam was observed in the near-infrared H and K spectral bands, wavelengths well suited to measure the size and study the geometry of the hot dust surrounding CI Cam. The analysis of the visibility data over an 8 year period from soon after the 1998 outburst to 2006 shows that the dust visibility has not changed over the years. The visibility data shows that CI Cam is elongated which confirms the disc-shape of the circumstellar environment and totally rules out the hypothesis of a spherical dust shell. Closure phase measurements show direct evidence of asymmetries in the circumstellar environment of CI Cam and we conclude that the dust surrounding CI Cam lies in an inhomogeneous disc seen at an angle. The near-infrared dust emission appears as an elliptical skewed Gaussian ring with a major axis a = 7.58 +/- 0.24 mas, an axis ratio r = 0.39 +/- 0.03 and a position angle theta = 35 +/- 2 deg.

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。

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