The age of the halo as determined from halo field stars

• 来源期刊: 天文和天体物理学研究
• 年，卷（期）: 2016,（3）
• 页码范围: 73-80
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-4527/16/3/044

摘要

The age of the Galactic halo is a critical parameter that can constrain the origin of the stellar halo.In general,the Galactic stellar halo is believed to be very old.However,different independent measurements and techniques based on various types of stars are required so that the age estimates of the Galactic halo are accurate,robust,and reliable.In this work,we provide a novel approach to determine the age of the halo with turn-off stars.We first carefully select 63 field halo tum-off stars from the literature.Then,we compare them with the GARSTEC model,which takes the process of atomic diffusion into account in the B-V vs.metallicity plane.Finally,we run Monte Carlo simulations to consider the uncertainty of the color index and obtain the age of 10.5 ± 1.5 Gyr.This result is in agreement with previous studies.Future works are needed to collect more turn-off samples with more accurate photometry to reduce the uncertainty of the age.