在过渡盘中的一个主要的不对称尘埃陷
Nienke van der Marel1, Ewine F van Dishoeck, Simon Bruderer
1Leiden Observatory, Leiden University, Leiden, Netherlands. nmarel@strw.leidenuniv.nl
Science (New York, N.Y.)
|June 8, 2013
概括
天文学家使用阿塔卡马大毫米/亚毫米阵列 (ALMA) 观测发现了Oph IRS 48原行星盘中的尘埃陷. 这一发现支持了尘埃陷在行星形成过程中帮助克服粒子漂移的理论.
科学领域:
- * 天文学 * 天文学
- * 天体物理学 * 天体物理学
- * 星球科学 星球科学
背景情况:
- *行星形成理论面临挑战,包括原行星盘中的粒子向内漂移.
- * 假设尘埃陷通过集中颗粒来解决这些问题.
- *了解尘埃分布对于解释行星形成效率至关重要.
研究的目的:
- * 为了检测和描述Oph IRS 48的原行星盘中的尘埃陷.
- * 为了研究圆盘内不同大小的尘埃粒和气体的分布.
- * 测试尘埃陷形成的理论模型,特别是引诱的陷.
主要方法:
- *使用阿塔卡马大毫米/亚毫米阵列 (ALMA) 进行高分辨率观测.
- *分析了0.44毫米的连续辐射,以绘制大型尘埃颗粒的地图.
- *比较尘埃分布与中红外图像 (小尘埃) 和一氧化碳 (气体) 观测.
主要成果:
- * 在Oph IRS 48的一侧检测到一个明显的,半月形的尘埃陷,富含毫米大小的颗粒.
- *观察到较小的尘埃颗粒和气体集中在中心环中,与较大的颗粒形成鲜明对比.
- *观察到的大尘/气体与小尘/气体之间的空间分离与带诱导的尘埃陷模型相一致.
结论:
- * 在Oph IRS 48中检测到一个尘埃陷提供了支持行星形成中的尘埃陷理论的观测证据.
- *这些发现表明,伴侣诱导的旋可能是造成这种尘埃陷的原因.
- * 这一发现提供了对促进行星小行星形成的机制的洞察力,这些机制通过聚焦尘埃来促进行星小行星的形成.
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