文章基本信息

标题：Spectral analysis of the binary nucleus of the planetary nebula Hen 2-428 – first results
本地全文：下载
作者：Nicolle L. Finch ; Nicole Reindl ; Martin A. Barstow 等
期刊名称：Open Astronomy
电子版ISSN：2543-6376
出版年度：2018
卷号：27
期号：1
页码：57-61
DOI：10.1515/astro-2018-0017
语种：English
出版社：Walter de Gruyter GmbH & Co. KG
摘要：Abstract Identifying progenitor systems for the double-degenerate scenario is crucial to check the reliability of type Ia supernovae as cosmological standard candles. Santander-Garcia et al. (2015) claimed that Hen 2-428 has a doubledegenerate core whose combined mass significantly exceeds the Chandrasekhar limit. Together with the short orbital period (4.2 hours), the authors concluded that the system should merge within a Hubble time triggering a type Ia supernova event. Garcia-Berro et al. (2016) explored alternative scenarios to explain the observational evidence, as the high mass conclusion is highly unlikely within predictions from stellar evolution theory. They conclude that the evidence supporting the supernova progenitor status of the system is premature. Here we present the first quantitative spectral analysis of Hen 2-428which allows us to derive the effective temperatures, surface gravities and helium abundance of the two CSPNe based on state-of-the-art, non-LTE model atmospheres. These results provide constrains for further studies of this particularly interesting system.
关键词：Keywordssubdwarfplanetary nebulatype Ia