Azimuthal temperature variations in ISO-Oph 2 from multifrequency ALMA observations
Azimuthal temperature variations in ISO-Oph 2 from multifrequency ALMA observations
复制标题
多频 ALMA 观测中 ISO-Oph 2 的方位角温度变化
DOI：
10.1093/mnras/stad1981
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Casassus S
中科院分区：
文献类型：
--
作者：
Casassus S
环境影响，例如恒星飞越和外部辐射，被认为会影响星团形成过程中原行星盘的演化。先前在 225GHz 下拍摄的 ISO-Oph 2 双星阿塔卡马大型毫米/亚毫米阵列 (ALMA) 图像显示，主星盘中存在一种特殊的形态，这可能是由于副星可能飞越所致。在这里，我们报告了该系统在 97.5、145 和 405 GHz 下的新 ALMA 连续谱观测，这些观测揭示了强烈的形态变化。多频率位置对准使我们能够根据潜在的物理条件来解释这些光谱变化。 ISO-Oph 2A 在所有频率下都明显偏离其环的质心，并且圆盘是不平衡的，指向引力相互作用。然而，尘埃温度也随方位角变化，有两个峰值，其方向与蛇夫座复合体中最早的恒星HD 147889相连，表明它是主要的热源。 ISO-Oph 2 的恒星环境似乎驱动其密度结构和热平衡。
Environmental effects, such as stellar fly-bys and external irradiation, are thought to affect the evolution of protoplanetary discs in clustered star formation. Previous Atacama Large Millimetre/submillimetre Array (ALMA) images at 225 GHz of the ISO-Oph 2 binary revealed a peculiar morphology in the disc of the primary, perhaps due to a possible fly-by with the secondary. Here, we report on new ALMA continuum observations of this system at 97.5, 145, and 405 GHz, which reveal strong morphological variations. Multifrequency positional alignment allows us to interpret these spectral variations in terms of underlying physical conditions. ISO-Oph 2A is remarkably offset from the centroid of its ring, at all frequencies, and the disc is lopsided, pointing at gravitational interactions. However, the dust temperature also varies in azimuth, with two peaks whose direction connects with HD 147889, the earliest-type star in the Ophiuchus complex, suggesting that it is the dominant heat source. The stellar environment of ISO-Oph 2 appears to drive both its density structure and its thermal balance.