First direct detection of a polarized companion outside a resolved circumbinary disk around CS Chamaeleonis
First direct detection of a polarized companion outside a resolved circumbinary disk around CS Chamaeleonis
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首次直接探测到 CS Chamaeleonis 周围解析的环双星盘外的偏振伴星
DOI：
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发表时间：
2018
影响因子：
6.5
通讯作者：
N. Vogt
中科院分区：
文献类型：
--
作者：
C. Ginski;M. Benisty;R. V. Holstein;A. Juhász;T. Schmidt;G. Chauvin;J. D. Boer;M. Wilby;C. Manara;P. Delorme;F. Ménard;P. Pinilla;T. Birnstiel;M. Flock;C. Keller;M. Kenworthy;J. Milli;J. Olofsson;L. M. Pérez;F. Snik;N. Vogt
目标。要了解行星的形成，有必要研究行星系统的诞生环境。年轻行星形成盘的分辨成像使我们能够详细研究这种环境，并找到行星盘相互作用和盘演化的迹象。在本研究中，我们的目标是调查光谱双星金牛座 T 星 CS Cha 的星周环境。根据尚未解析的中远红外光度测定，预测 CS Cha 拥有一个带有大空腔的圆盘。此外，光谱能量分布模型表明显着的尘埃沉降，表明进化的圆盘可能显示出正在进行或完成的行星形成的迹象。
方法。我们使用ESO甚大望远镜（VLT）上的高对比度成像仪SPHERE以偏振差分成像模式观察CS Cha，以解析近红外散射光中的环双星盘。这些观测之后进行了 VLT/NACO L 波段观测，并以档案 VLT/NACO K 波段和哈勃太空望远镜 WFPC2 I 波段数据进行补充。
结果。我们首次在散射光下解析了 CS Cha 周围的致密环双星盘。我们发现了一个光滑、低倾角的圆盘，其外半径约为 55 au（165 pc）。我们没有检测内部空腔，但发现空腔尺寸的上限约为 15 au。此外，我们还发现了一个微弱的共动伴星，预计与环双星盘外的中心双星相距 210 个天文单位。伴星在偏振光中被检测到并显示出极端程度的偏振（J 波段为 13.7 ± 0.4%）。伴星的 J 和 H 波段星等与几 MJup 的质量兼容。然而，K、L 和 I 波段数据使这一结论受到质疑。我们通过辐射传输模型探索未解析的环绕伴盘是否可以负责高偏振和复杂的光度测定。我们发现，这组观测结果最好用一颗严重灭绝的低质量（~20 MJup）褐矮星或带有未解析的圆盘和尘埃包层的大质量行星来解释。
Aims. To understand planet formation it is necessary to study the birth environment of planetary systems. Resolved imaging of young planet forming disks allows us to study this environment in great detail and find signs of planet-disk interaction and disk evolution. In the present study we aim to investigate the circumstellar environment of the spectroscopic binary T Tauri star CS Cha. From unresolved mid-to far-infrared photometry it is predicted that CS Cha hosts a disk with a large cavity. In addition, spectral energy distribution modeling suggests significant dust settling, pointing toward an evolved disk that may show signs of ongoing or completed planet formation.
Methods. We observed CS Cha with the high contrast imager SPHERE at the ESO Very Large Telescope (VLT) in polarimetric differential imaging mode to resolve the circumbinary disk in near-infrared scattered light. These observations were followed up by VLT/NACO L-band observations and complemented by archival VLT/NACO K-band and Hubble Space Telescope WFPC2 I-band data.
Results. We resolve the compact circumbinary disk around CS Cha for the first time in scattered light. We find a smooth, low inclination disk with an outer radius of ~55 au (at 165 pc). We do not detect the inner cavity but find an upper limit for the cavity size of ~15 au. Furthermore, we find a faint comoving companion with a projected separation of 210 au from the central binary outside of the circumbinary disk. The companion is detected in polarized light and shows an extreme degree of polarization (13.7 ± 0.4% in the J band). The J- and H-band magnitudes of the companion are compatible with masses of a few MJup. However, K-, L-, and I-band data draw this conclusion into question. We explore with radiative transfer modeling whether an unresolved circum-companion disk can be responsible for the high polarization and complex photometry. We find that the set of observations is best explained by a heavily extincted low-mass (~20 MJup) brown dwarf or high-mass planet with an unresolved disk and dust envelope.
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Chamaeleon 恒星形成区年轻低质量双星和多个系统的天体测量确认
DOI：
10.1051/0004-6361/201118410
发表时间：
2012
期刊：
arXiv: Solar and Stellar Astrophysics
影响因子：
--
作者：
Vogt N;Schmidt T.O.B;Neuhäuser R;Bedalov A;Roell T;Seifahrt A;Mugrauer M.
通讯作者：
Mugrauer M.
对年轻恒星和褐矮星直接成像的亚恒星伴星的天体测量后续观测
影响因子：
4.8
作者：
Ginski C;Schmidt T.O.B;Mugrauer M;Neuhäuser R;Vogt N;Errmann R;Berndt A.
通讯作者：
Berndt A.
影响因子：
4.8
作者：
Bate, Matthew R.
通讯作者：
Bate, Matthew R.
适合 VLTI 观测的前主序谱双星，
影响因子：
6.5
作者：
Guenther;Esposito;Covino;Alcalá;Cusano;Stecklum
通讯作者：
Stecklum