The cooling time of white dwarfs produced from type Ia supernovae

• Published in: Research in astronomy and astrophysics Vol. 10; no. 9; pp. 927 - 934
• Main Authors: Meng, Xiang-Cun, Yang, Wu-Ming, Li, Zhong-Mu
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.09.2010; School of Physics and Chemistry,Henan Polytechnic University,Jiaozuo 454000,China%College of Physics and Electronic Information,Dali University,Dali 671003,China; National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China
• Subjects: Ia型超新星; 冷却时间; 大肠杆菌; 宇宙学参数; 开发模型; 相对含量; 超新星爆炸; general; white dwarfs-stars; stars; supernovae
• ISSN: 1674-4527; 2397-6209
• DOI: 10.1088/1674-4527/10/9/006

Type Ia supernovae （SNe Ia） play a key role in measuring cosmological parameters, in which the Phillips relation is adopted. However, the origin of the relation is still unclear. Several parameters are suggested, e.g. the relative content of carbon to oxygen （C/O） and the central density of the white dwarf （WD） at ignition. These parameters are mainly determined by the WD＇s initial mass and its cooling time, respectively. Using the progenitor model developed by Meng ＆ Yang, we present the distributions of the initial WD mass and the cooling time. We do not find any correlation between these parameters. However, we notice that as the range of the WD＇s mass decreases, its average value increases with the cooling time. These results could provide a constraint when simulating the SN Ia explosion, i.e. the WDs with a high C/O ratio usually have a lower central density at ignition, while those having the highest central density at ignition generally have a lower C/O ratio. The cooling time is mainly determined by the evolutionary age of secondaries, and the scatter of the cooling time decreases with the evolutionary age. Our results may indicate that WDs with a long cooling time have more uniform properties than those with a short cooling time, which may be helpful to explain why SNe Ia in elliptical galaxies have a more uniform maximum luminosity than those in spiral galaxies.