FORMING DUST PRECURSORS IN THE INNER ENVELOPES OF CARBON-RICH AGB STARS

被引：12

作者：

CHERCHNEFF, I ^{[1
]}

机构：

[1] ROYAL OBSERV,EDINBURGH EH9 3JH,MIDLOTHIAN,SCOTLAND

来源：

ASTROPHYSICS AND SPACE SCIENCE | 1995年 / 224卷 / 1-2期

关键词：

D O I：

10.1007/BF00667875

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The formation of polycyclic aromatic hydrocarbon (PAH) molecules is studied in the inner envelope of a typical carbon-rich AGE star. The deep envelope is formed of layers of gas that experience the passage of strong periodic shocks forming close to the stellar photosphere. The parcels of gas then follow quasi-ballistic trajectories which are characterized by high gas densities. A chemical scheme based on combustion chemistry is applied to shocked layers of gas, and a PAH formation yield is calculated. PAHs up to coronene (C24H12) survive shocks with strengths of similar to 10 km s(-1), and they accumulate in the gas parcel over several stellar pulsations. This result illustrates that any C-rich AGE star can nucleate dust precursors in its envelope.

引用

页码：379 / 382

页数：4

共 11 条

[1] A PERIODIC SHOCK-WAVE MODEL FOR MIRA VARIABLE ATMOSPHERES [J].