The thermal proximity effect around high redshift quasars

高红移类星体周围的热邻近效应

• 批准号: 2883987
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2883987
• 关键词: thermal; proximity; effect; around; redshift

The thermal state of the intergalactic medium (IGM) provides an indirect probe of both the H-I and He-II reionisation epochs. However, the very late reionisation models ending at z~5.3 favoured by Lyman-alpha forest observations and Lyman-alpha emitter clustering are in tension with IGM temperature constraints from quasar proximity zones at z~6; the latter prefer (at 95% confidence) that reionisation completes at z>6.5. Hence, either there are problems with the IGM temperature measurements at z>6, or the cold IGM around these high redshift quasars presents a challenge to the currently favoured very late reionisation models. The goal of this project will be to revisit measurements of the IGM temperature around z>5 quasars. This will use the Sherwood-Relics simulations, combined with radiative transfer modelling and archival echelle spectra of Lyman-alpha absorption. The timing of reionisation and the relative contribution of sources with non-thermal spectra to the reionisation photon budget will be addressed.

星系际介质（IGM）的热态提供了对H-I和He-II再电离时代的间接探测。然而，Lyman-alpha森林观测和Lyman-alpha发射器集群所支持的z~5.3结束的极晚再电离模型受到类星体接近带z~6的IGM温度约束的紧张；后者更倾向于（以95%的置信度）再电离在z - 6.5完成。因此，要么是在z>6的IGM温度测量存在问题，要么是这些高红移类星体周围的冷IGM对目前受欢迎的非常晚的再电离模型提出了挑战。这个项目的目标将是重新测量zbbbb50类星体周围的IGM温度。这将使用sherwood - relic模拟，结合辐射传输模型和存档的莱曼- α吸收梯队光谱。将讨论再电离的时间和非热光谱源对再电离光子收支的相对贡献。