Trace elements and evolution of PG 1159 stars

PG 1159星的微量元素和演化

• 批准号: 5382792
• 负责人: Dr. Thomas Rauch
• 金额: --
• 依托单位: Abteilungen Astronomie und Hochenergieastrophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2002
• 资助国家: 德国
• 起止时间: 2001-12-31 至 2002-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5382792?language=en
• 关键词: Trace; elements; evolution; PG; 1159

Modern spectral analysis of hot helium-rich post-AGB stars has improved our picture of their evolution: They are likely so-called "born-again post-AGB" stars. However, the results of our analyses had been inconsistent with predictions of standard evolutionary calculations: These had shown the observed abundance pattern deep inside the atmosphere covered by thick helium and hydrogen shells and thus, far from being observable. Newly developed evolutionary models can predict now these abundances. The photospheric hydrogen, nitrogen and neon content are important indicators to test these calculations and to give constraints for the further evolution of these stars.

对热富氦后 AGB 恒星的现代光谱分析改善了我们对其演化的认识：它们很可能是所谓的“重生后 AGB”恒星。然而，我们的分析结果与标准进化计算的预测不一致：这些结果显示了在厚厚的氦和氢壳层覆盖的大气深处观察到的丰度模式，因此远远无法观察到。新开发的进化模型现在可以预测这些丰度。光球层的氢、氮和氖含量是检验这些计算并为这些恒星进一步演化提供约束的重要指标。