The circumbinary disc around the J-type C-star IRAS 18006-3213
The circumbinary disc around the J-type C-star IRAS 18006-3213
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DOI：
10.1051/0004-6361:20066516
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发表时间：
2007-03
影响因子：
6.5
通讯作者：
P. Deroo;H. Winckel;T. Verhoelst;M. Min;M. Reyniers;L. Waters
中科院分区：
文献类型：
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作者：
P. Deroo;H. Winckel;T. Verhoelst;M. Min;M. Reyniers;L. Waters
背景：在普遍接受的但文献很少的模型中，硅酸盐j型c星是双星，其硅酸盐辐射来自环双星或环伴星盘。目的：我们旨在通过对IRAS 18006-3213进行全面的光谱和空间观测研究来验证这一假设。方法：在45 ~ 100 m的多个基线上获取、分析和模拟高空间分辨率干涉VLTI/MIDI观测数据。结果：所有观测结果都解析了物体，显示了n波段发射（~30 mas）的致密性。此外，最高空间分辨率数据在8.3 μ m左右显示出显著的差相位跳变。这证明了n波段发射的不对称性质。此外，单望远镜的n波段光谱显示了高度加工的硅酸盐颗粒的特征。这些数据被用来确认IRAS 18006-3213的硅酸盐j型c星模型。我们表明，最有利的尘埃几何模型是一个稳定的环双星盘围绕着系统，看到在一个中间的倾斜。结论：硅酸盐j型c星IRAS 18006-3213的数据提供了富氧尘埃被困在环双星盘中的证据。这个圆盘的形成可能与中心恒星的双星特性有关。根据智利欧洲南方天文台收集的观测数据。项目ID: 073.D-610(A)。
Context: In the generally accepted, but poorly documented model, silicate J-type C-stars are binary objects for which the silicate emission originates from a circumbinary or a circumcompanion disc. Aims: We aim at testing this hypothesis by a thorough spectral and spatial observational study of one object: IRAS 18006-3213 . Methods: We obtained, analysed and modeled high spatial resolution interferometric VLTI/MIDI observations on multiple baselines ranging from 45 m to 100 m. Results: All observations resolved the object and show the very compact nature of the N-band emission (~30 mas). In addition, the highest spatial resolution data show a significant differential phase jump around 8.3 mum. This demonstrates the asymmetric nature of the N-band emission. Moreover, the single telescope N-band spectrum shows the signature of highly processed silicate grains. These data are used to confirm the model on silicate J-type C-stars for IRAS 18006-3213 . We show that the most favourable model of the dust geometry is a stable circumbinary disc around the system, seen under an intermediate inclination. Conclusions: The data presented on the silicate J-type C-star IRAS 18006-3213 provide evidence that the oxygen rich dust is trapped in a circumbinary disc. The formation of this disc is probably linked to the binary nature of the central star. Based on observations collected at the European Southern Observatory, Chile. Program ID: 073.D-610(A).