Searching for long period pulsations in He-rich subdwarfs

寻找富 He 亚矮星中的长周期脉动

• 批准号: 404880276
• 负责人: Professor Dr. Stephan Geier
• 金额: --
• 依托单位: Institut für Physik und Astronomie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/404880276?language=en
• 关键词: Searching; long; period; pulsations; He

Hot subdwarf stars are He-core burning stars that have lost their H-rich envelopes. While most hot subdwarfs show almost pure H atmospheres, a small fraction of these stars show a mixed H/He surface composition. These stars are expected to be in a fast stage immediately after the He-core flash, where gravitational settling did not turn the atmosphere H-pure yet. During this phase they are expected to undergo He-core subflashes, which are predicted to drive pulsations. The confirmation of stellar pulsations driven by the He-core flash would be the first direct confirmation of the existence of the He-subflashes themselves. We granted four nights of observing time with the BUSCA instrument at the Calar Alto observatory to pursue an ad hoc search of stellar oscillations in 14 hot subdwarfs with mixed H/He atmospheres.

热亚矮星是氦核燃烧的恒星，失去了富氢的外壳。虽然大多数热的次矮星显示出几乎纯H的大气层，但这些恒星中的一小部分显示出混合的H/He表面成分。这些恒星预计将在氦核闪光后立即处于快速阶段，引力沉降尚未使大气变成H纯。在这一阶段，它们预计将经历氦核次闪光，预计将驱动脉动。确认氦核闪光驱动的恒星脉动将是第一次直接确认氦次闪光本身的存在。我们授予四个晚上的观测时间与布斯卡仪器在卡拉尔阿尔托天文台进行特别搜索的恒星振荡在14个热亚矮星混合H/He大气。