We present infrared photometry of the WC8 Wolf-Rayet system WR 48a observed with telescopes at ESO, the SAAO and the AAT between 1982 and 2011 which show a slow decline in dust emission from the previously reported outburst in 1978--79 until about 1997, when significant dust emission was still evident. This was followed by a slow rise, accelerating to reach and overtake the first (1978) photometry, demonstrating that the outburst observed in 1978--79 was not an isolated event, but that they recur at intervals of 32+ years. This suggests that WR 48a is a long-period dust maker and colliding-wind binary (CWB). The locus of WR 48a in the (H-L), K colour-magnitude diagram implies that the rate of dust formation fell between 1979 and about 1997 and then increased steadily until 2011. Superimposed on the long-term variation are secondary (`mini') eruptions in (at least) 1990, 1994, 1997, 1999 and 2004, characteristic of relatively brief episodes of additional dust formation. Spectra show evidence for an Oe or Be companion to the WC8 star, supporting the suggestion that WR 48a is a binary system and indicating a system luminosity consistent with the association of WR 48a and the young star clusters Danks 1 and Danks 2. The range of dust formation suggests that these stars are in an elliptical orbit having e ~ 0.6. The size of the orbit implied by the minimum period, together with the WC wind velocity and likely mass-loss rate, implies that the post-shock WC wind is adiabatic throughout the orbit -- at odds with the observed dust formation. A similar conflict is observed in the `pinwheel' dust-maker WR 112.
Probing disk dynamics and dust evolution through shadows in protoplanetary disks: A case study of the HD 142527 disk
Institute of Astronomy and Astrophysics, Academia Sinica（中央研究院天文及天文物理研究所）；Institute of Science Tokyo（东京科学大学）；The University of Tokyo（东京大学）；Kogakuin University（工学馆大学）
Variable Winds and Dust Formation in R Coronae Borealis Stars
我们已经观察到的P-天鹅座和不对称，蓝移的吸收轮廓在He I 10830线的12 R Coronae Borealis（RCB）的恒星在短（1个月）和长（3年）的时间尺度，寻找与他们的尘埃形成事件的变化。在几乎所有的情况下，强度和终极速度的线变化显着，并与尘埃形成事件。蓝移速度约400 km/s的强吸收特征出现在可见光亮度下降期间，并在恢复到最大亮度后持续约100天。在下降期和恢复期之外，存在着速度稍低的小余风。这些相关性支持了这样一种模型，即在恒星附近最近形成的尘埃被辐射压力高速向外推动，并将气体一起拖走。
The Timescales of Embedded Star Formation as Observed in STARFORGE
University of Washington（华盛顿大学）；Center for Computational Astrophysics, Flatiron Institute（平研究所计算天体物理中心）；Department of Astronomy, University of Texas at Austin（德克萨斯大学奥斯汀分校天文学系）；Space Telescope Science Institute（太空望远镜科学研究所）；Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University（西北大学交叉天体物理探索与研究中心及物理与天文系）；Department of Physics, University of Alberta（阿尔伯塔大学物理系）；National Radio Astronomy Observatory（国家射电天文台）；Max-Planc（马克斯·普朗克）
A dust-free hierarchically nested supermassive-star model for James Webb Space Telescope Little Red Dots
Universitat Politècnica de València（瓦伦西亚理工大学）；Max Planck Institute for Extraterrestrial Physics（马克斯·普朗克地外物理研究所）；Kavli Institute for Astronomy and Astrophysics at Peking University（北京大学科维理天文与天体物理研究所）
