The clumpy structure of ? Eridani's debris disc revisited by ALMA
The clumpy structure of ? Eridani's debris disc revisited by ALMA
复制标题
的块状结构？
DOI：
10.1093/mnras/stad938
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Booth M
中科院分区：
文献类型：
--
作者：
Booth M
波江座是离太阳最近的星星，已知拥有碎片盘。先前在（亚）毫米波段的观测可能在盘中发现了星团结构，并将其归因于与一颗（迄今为止）未被发现的行星的相互作用。然而，先前的观察无法区分椎间盘结构和背景混淆。在这里，我们展示了整个圆盘的第一张阿尔马图像，分辨率为1.6 × 1.2 arcsec 2。我们清楚地探测到了星星、主带和两点源。这些数据的分辨率和灵敏度使我们能够清楚地区分背景星系（显示为点源）和圆盘发射。我们表明，两点源是一致的背景星系。在考虑这些因素之后，我们发现主带中仍然存在解析残差，包括两个具有>3σ显著性的团块-一个在星星的东部，另一个在西北部。我们执行N体模拟证明，迁移的行星可以形成类似的结构，所观察到的陷阱星子共振。我们发现，所观察到的特征可以复制一个迁移的行星捕获星子在2：1的平均运动共振和最突出的团块的对称性意味着行星应该有一个位置角为<$10 °或<$190 °。多个历元的观测是必要的，以测试所观察到的特征是否围绕星星旋转。
ϵ Eridani is the closest star to our Sun known to host a debris disc. Prior observations in the (sub-)millimetre regime have potentially detected clumpy structure in the disc and attributed this to interactions with an (as yet) undetected planet. However, the prior observations were unable to distinguish between structure in the disc and background confusion. Here, we present the first ALMA image of the entire disc, which has a resolution of 1.6 × 1.2 arcsec2. We clearly detect the star, the main belt, and two-point sources. The resolution and sensitivity of this data allow us to clearly distinguish background galaxies (that show up as point sources) from the disc emission. We show that the two-point sources are consistent with background galaxies. After taking account of these, we find that resolved residuals are still present in the main belt, including two clumps with a >3σ significance – one to the east of the star and the other to the north-west. We performN-body simulations to demonstrate that a migrating planet can form structures similar to those observed by trapping planetesimals in resonances. We find that the observed features can be reproduced by a migrating planet trapping planetesimals in the 2:1 mean motion resonance and the symmetry of the most prominent clumps means that the planet should have a position angle of either ∼10° or ∼190°. Observations over multiple epochs are necessary to test whether the observed features rotate around the star.