Silicon in the dust formation zone of IRC +10216
Silicon in the dust formation zone of IRC +10216
复制标题
IRC 10216 粉尘形成区中的硅
DOI：
10.1051/0004-6361/201014562
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发表时间：
2010
影响因子：
6.5
通讯作者：
Decin L
中科院分区：
文献类型：
--
作者：
Decin L
星际介质主要是由演化中的低质量和中等质量恒星喷出的物质富集的。这些恒星的外流产生了一个环绕恒星的包层，其中发生了丰富的气相和尘埃成核化学反应。我们用Herschel星载的PACS（55-210μm）和SPIRE（194-672μm）光谱仪观测了最近的富碳演化星星IRC +10216。我们发现几十条来自SiS和SiO的谱线，包括来自v = 1振动能级的谱线。对于SiS，这些跃迁的范围高达J = 124-123，对应于6700 K左右的能量，而对于SiO，最高可检测的跃迁为J = 90-89，对应于8400 K左右的能量。这两种物质都追踪到IRC +10216的尘埃形成区，它们探测到的跃迁所涉及的广泛能量范围使我们能够推导出气体的物理性质以及每种物质形成的特定区域。这使我们能够检查的准确性，化学物质平衡模型和建议的消耗SiS和SiO由于吸积到尘埃颗粒。
The interstellar medium is enriched primarily by matter ejected from evolved low and intermediate mass stars. The outflows from these stars create a circumstellar envelope in which a rich gas-phase and dust-nucleation chemistry takes place. We observed the nearest carbon-rich evolved star, IRC +10216, using the PACS (55–210μm) and SPIRE (194–672μm) spectrometers on boardHerschel. We find several tens of lines from SiS and SiO, including lines from thev= 1 vibrational level. For SiS these transitions range up toJ= 124–123, corresponding to energies around 6700 K, while the highest detectable transition isJ= 90–89 for SiO, which corresponds to an energy around 8400 K. Both species trace the dust formation zone of IRC +10216, and the broad energy ranges involved in their detected transitions permit us to derive the physical properties of the gas and the particular zone in which each species has been formed. This allows us to check the accuracy of chemical thermodynamical equilibrium models and the suggested depletion of SiS and SiO due to accretion onto dust grains.