VLTI/MATISSE对$\eta$ Pictoris周围热尘埃的观测：使用MATISSE观测暗弱天体
VLTI/MATISSE observations of the hot dust around $β$ Pictoris: Observing faint objects with MATISSE
- Univ. Grenoble Alpes, CNRS, IPAG（格勒诺布尔阿尔卑斯大学）
- Univ. Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange（蔚蓝海岸大学，蔚蓝海岸天文台）
- Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, HUN-REN（孔科利天文台，地球与天文学研究中心）
- CSFK, MTA Centre of Excellence（匈牙利科学院天文学研究所，MTA卓越中心）
- Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）
- NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
通过VLTI/MATISSE的L波段干涉观测，研究β Pictoris周围热尘埃的空间分布，发现其位于升华半径附近、高度倾斜且与碎片盘错位，由亚微米颗粒组成，支持系外彗星活动起源。
AI中文摘要：
背景：热系外黄道尘埃已在约20%的邻近主序星周围被探测到，表明它是系外行星系统的常见特征。然而，其空间分布和颗粒性质仍知之甚少。目标：我们旨在表明，通过对光学长基线干涉测量数据的详细分析，可以约束β Pictoris（一个拥有两颗已知行星和一群系外彗星的标志性行星系统）周围热尘埃的空间分布。方法：我们使用VLTI的MATISSE在约3.5微米的L波段对β Pictoris进行了观测。我们开发了一种通过估计完整数据协方差矩阵来评估可见度测量中相关性的方法，并用几何亮度分布对星周发射进行建模。结果：我们在β Pictoris周围探测到与热系外黄道尘埃一致的星周发射。在考虑和不考虑数据相关性的情况下对发射进行建模，表明它们对推断的尘埃性质有显著影响。最佳拟合模型揭示了一个位于升华半径附近的紧凑（约0.05天文单位）、高倾角的尘埃结构，在天空上与延伸的侧向外盘错位约60度。它在3.4微米处贡献了总通量的约4%-7.5%，并由亚微米大小的颗粒组成。数据也与位于约1天文单位处的额外尘埃成分兼容。结论：对于β Pictoris，将热系外黄道尘埃置于升华半径附近并由亚微米颗粒组成的二十年旧范式，在MATISSE数据的详细分析中得到了观测支持。与已知碎片盘的错位进一步支持了其与系外彗星活动的联系。
英文摘要：
Context: Hot exozodiacal dust has been detected around approximately 20% of nearby main-sequence stars, indicating that it is a common feature of extrasolar planetary systems. However, its spatial distribution and grain properties remain poorly understood. Aims: We aim to show that the spatial distribution of hot dust around beta Pictoris, an iconic planetary system with two known planets and a population of exocomets, can be constrained through a detailed analysis of optical long-baseline interferometry data. Methods: We obtained L-band observations at approximately 3.5 microns of beta Pictoris with MATISSE at the VLTI. We developed a method to assess correlations in the visibility measurements by estimating the full data covariance matrix, and modeled the circumstellar emission with geometric brightness distributions. Results: We detect circumstellar emission around beta Pictoris consistent with hot exozodiacal dust. Modeling the emission with and without accounting for data correlations demonstrates their significant impact on the inferred dust properties. The best-fit model reveals a compact (approximately 0.05 au), highly inclined dust structure near the sublimation radius, misaligned by approximately 60 degrees on the sky with respect to the extended edge-on outer disk. It contributes approximately 4%-7.5% of the total flux at 3.4 microns and is composed of submicron-sized grains. The data are also compatible with an additional dust component near 1 au. Conclusions: For beta Pictoris, the two-decade-old paradigm placing hot exozodiacal dust near the sublimation radius and consisting of submicron-sized grains finds observational support in the detailed analysis of MATISSE data. The misalignment with the known debris disk further supports a link to exocometary activity.
