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流体养SVS13-A原流体系统:天体化学揭示了增积冲击?
Eleonora Bianchi1, Ana López-Sepulcre2,3, Cecilia Ceccarelli2
1Excellence Cluster ORIGINS, Boltzmannstraße 2, Garching bei München, 85748, Germany. eleonora.bianchi@origins-cluster.de.
Faraday discussions
|June 19, 2023
概括
高分辨率的ALMA观测揭示了SVS13-A二进制星系中尘埃积聚流体的化水 (HDO) 排放. 这种辐射可能源于对原恒星产生影响的积累冲击.
科学领域:
- 天体物理学和天体化学
- 恒星的形成和进化
- 星球系统的形成行星系统的形成
背景情况:
- 双星系统SVS13-A是研究早期恒星形成的关键目标.
- 了解前恒星环境中的分子发射对于追踪积累过程至关重要.
研究的目的:
- 调查SVS13-A二进制系统中脱水 (HDO) 和二氧化硫 (SO2) 排放的来源.
- 分析HDO和SO2与积累结构相关的空间分布.
- 探索在积累流中负责分子发射的物理条件和过程.
主要方法:
- 使用阿塔卡马大毫米/亚毫米阵列 (ALMA) 的高角度分辨率观测.
- 对分子排放线的分析,特别是HDO和SO2.
- 分子排放分布与形式胺 (NH2CHO) 和尘埃积累流的比较.
- 基于更新的结合能量分布计算热升华温度.
主要成果:
- 检测到HDO和SO2的分子排放,并与SVS13-A二进制系统 (VLA4A和VLA4B) 的两个组件相关联.
- 在一个尘埃积聚流体中发现了额外的HDO发射元件,该流体位于距离具有蓝色转移速度的原恒星≥120 AU.
- 在流体中观察到的HDO辐射与VLA4A.的流体-磁盘接口上的积累冲击模型相一致.
结论:
- 该研究提出了增积冲击机制作为SVS13-A.增积流体中HDO排放的主要来源.
- 热溶解可能会在活跃积累爆发期间导致排放.
- 这些发现为早期恒星和行星形成过程中发生的复杂的物理和化学过程提供了洞察力.
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