Title: Origin of central abundances in the hot intra-cluster medium - II. Chemical enrichment and supernova yield models Show Chinese title

Title: 中心丰度在热星系团介质中的起源 - II. 化学富集和超新星产率模型

Abstract: The hot intra-cluster medium (ICM) is rich in metals, which are synthesised by supernovae (SNe) and accumulate over time into the deep gravitational potential well of clusters of galaxies. Since most of the elements visible in X-rays are formed by type Ia (SNIa) and/or core-collapse (SNcc) supernovae, measuring their abundances gives us direct information on the nucleosynthesis products of billions of SNe since the epoch of the star formation peak (z~2-3). In this study, we compare the most accurate average X/Fe abundance ratios (compiled in a previous work from XMM-Newton EPIC and RGS observations of 44 galaxy clusters, groups, and ellipticals), representative of the chemical enrichment in the nearby ICM, to various SNIa and SNcc nucleosynthesis models found in the literature. The use of a SNcc model combined to any favoured standard SNIa model (deflagration or delayed-detonation) fails to reproduce our abundance pattern. In particular, the Ca/Fe and Ni/Fe ratios are significantly underestimated by the models. We show that the Ca/Fe ratio can be reproduced better, either by taking a SNIa delayed-detonation model that matches the observations of the Tycho supernova remnant, or by adding a contribution from the Ca-rich gap transient SNe, whose material should easily mix into the hot ICM. On the other hand, the Ni/Fe ratio can be reproduced better by assuming that both deflagration and delayed-detonation SNIa contribute in similar proportions to the ICM enrichment. In either case, the fraction of SNIa over the total number of SNe (SNIa+SNcc) contributing to the ICM enrichment ranges within 29-45%. This fraction is found to be systematically higher than the corresponding SNIa/SNe fraction contributing to the enrichment of the proto-solar environnement (15-25%). We also discuss and quantify two useful constraints on both SNIa and SNcc that can be inferred from the ICM abundance ratios. Show Chinese abstract

Abstract: 热的星系团介质（ICM）富含金属，这些金属是由超新星（SNe）合成的，并随时间积累到星系团的深引力势阱中。 由于在X射线中可见的大部分元素是由Ia型（SNIa）和/或核心坍缩（SNcc）超新星形成的，测量它们的丰度可以为我们提供关于自恒星形成峰值时期（z~2-3）以来数百亿颗超新星的核合成产物的直接信息。 在本研究中，我们将最准确的平均X/Fe丰度比（根据之前一项工作从XMM-Newton EPIC和RGS对44个星系团、星系群和椭圆星系的观测结果整理得到），代表附近ICM的化学富集，与文献中各种SNIa和SNcc核合成模型进行比较。 使用一个SNcc模型结合任何被青睐的标准SNIa模型（亚爆或延迟爆轰）都无法再现我们的丰度模式。 特别是，Ca/Fe和Ni/Fe比值被模型显著低估。 我们表明，通过采用与Tycho超新星遗迹观测相匹配的SNIa延迟爆轰模型，或者通过添加来自富含钙的间隙瞬变超新星的贡献，可以更好地再现Ca/Fe比值，这些超新星的物质应容易混合到热的ICM中。 另一方面，通过假设亚爆和延迟爆轰SNIa以相似的比例贡献于ICM的富集，可以更好地再现Ni/Fe比值。 无论哪种情况，贡献于ICM富集的SNIa占总超新星数量（SNIa+SNcc）的比例范围在29-45%之间。 这一比例被发现系统性地高于对应于原始太阳环境富集的SNIa/SNe比例（15-25%）。 我们还讨论并量化了两个可用于SNIa和SNcc的有用约束，这些约束可以从ICM丰度比中推断出来。