论文标题
围绕年轻中间质量恒星的有效尘埃径向漂移
Efficient Dust Radial Drift Around Young Intermediate-mass Stars
论文作者
论文摘要
外部球星的径向速度和直接成像观测表明，中间质量恒星的巨型行星频率可能会降低（$ 2.5-8 \，M_ \ odot $）。可能阻碍其形成的关键机制尚不清楚。从理论的角度来看，中间质量恒星周围的行星形成可能发生在较长的时间尺度上，这与快速迁移和有效的光蒸发可能会阻止这些环境中的行星形成。在这封信中，我们研究了当考虑出色的进化时，我们研究了圆盘中灰尘颗粒的径向漂移的时间演变。我们证明，粒子在中间质量恒星周围的颗粒漂移速度在1美元 - $ 2 MYR后急剧增加，这可能形成了行星形成的第一步，这可能会形成难以克服的障碍。这种高径向漂移可以解释在中间质量恒星周围缺乏磁盘检测到3 $ -4- $ 4 MYR，而不是低质量恒星（$ <2.5 \，m_ \ odot $），其中漂移可能不是磁盘进化的最大影响因素。这些磁盘的未来高分辨率图像可以帮助我们解释为什么围绕中间质量恒星的行星可能很少见。此外，我们可以探索有效的尘埃径向漂移的作用实际上会阻碍行星围绕中间质量恒星形成 - 还是其他方式。
The radial velocities and direct imaging observations of exoplanets have suggested that the frequency of giant planets may decrease for intermediate-mass stars ($2.5-8\,M_\odot$). The key mechanism that could hinder their formation remains unclear. From a theoretical point of view, planet formation around intermediate-mass stars may take place on longer timescales, which -- coupled with fast migration and efficient photoevaporation -- may prevent planetary formation in these environments. In this letter, we investigate the temporal evolution of the radial drift for dust particles in disks when stellar evolution is taken into account. We demonstrate that the particle drift velocity around intermediate-mass stars sharply increases after 1$-$2 Myr, potentially forming a difficult barrier to overcome in the first steps of planet formation. This high radial drift could explain the lack of disk detections around intermediate-mass stars older than 3$-$4 Myr, as opposed to low-mass stars ($<2.5\,M_\odot$), where the drift may not be the most impactful factor for the disk evolution. Future high-resolution images of these disks can help us to explain why planets around intermediate-mass stars may be rare. In addition, we can explore whether the role of efficient dust radial drift does in fact hinder planet formation around intermediate-mass stars -- or otherwise.
