The chemical evolution of damped Lyman alpha systems and Lyman-limit systems at low redshift

低红移下阻尼莱曼α系统和莱曼极限系统的化学演化

• 批准号: 215312657
• 负责人: Professor Dr. Philipp Richter
• 金额: --
• 依托单位: Institut für Physik und Astronomie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/215312657?language=en
• 关键词: chemical; evolution; damped; Lyman; alpha

The so-called damped Lyman  systems (DLAs), sub-DLAs and Lyman-limit systems (LLS) represent strong intervening absorption-line systems in the spectra of distant quasars. These absorbers most likely arise in the neutral gas disks of galaxies and their surrounding gaseous halos and trace most of the neutral gas mass in the Universe. Knowledge about the chemical composition of DLAs, sub-DLAs and LLS is of fundamental importance to constrain the enrichment history of galaxies through cosmic time. Because of the small cross section of DLAs, sub-DLAs and LLS in quasar spectra and the limited amount of high-resolution ultraviolet (UV) quasar spectra, very little is known about the chemical evolution of the DLAs and LLS at redshifts z  0.5. In this project, we will use optical high-resolution spectra from VLT/UVES together with UV absorption-line data from HST/COS to analyze chemical abundances in a sample of ~ 30 DLAs, sub-DLAs and LLS at z  0.5. The combination of optical and UV data will allow us to derive accurate metallicities and dust-depletion patterns for elements like H, O, Si, N, C, Fe, Ca, Na, Ti, and others. Our study aims at improving our understanding of the metal-enrichment of galaxies and their gaseous environment in the local Universe.

阻尼莱曼极限系统（DLAs）、次阻尼莱曼极限系统（LLS）是遥远类星体光谱中强干涉吸收线系统的代表。这些吸收体最有可能出现在星系的中性气体盘及其周围的气体晕中，并追踪宇宙中大部分的中性气体质量。有关DLAs，sub-DLAs和LLS的化学成分的知识对于限制星系在宇宙时间内的富集历史具有根本的重要性。由于类星体光谱中DLAs、sub-DLAs和LLS的截面很小，而高分辨率的紫外类星体光谱数量有限，因此人们对红移z ≥ 0.5的DLAs和LLS的化学演化知之甚少。在这个项目中，我们将使用VLT/UVES的光学高分辨率光谱以及HST/COS的紫外吸收线数据来分析z = 0.5的约30个DLAs，sub-DLAs和LLS样品中的化学丰度。光学和紫外数据的结合将使我们能够获得H，O，Si，N，C，Fe，Ca，Na，Ti等元素的准确金属丰度和尘埃贫化模式。我们的研究旨在提高我们对星系的金属富集及其在本地宇宙中的气体环境的理解。

项目成果

Multiple origins for the DLA at zabs = 0.313 toward PKS 1127–145 indicated by a complex dust depletion pattern of Ca, Ti, and Mn

DLA 在 zabs = 0 313 处朝向 PKS 1127â145 的多个起源，由 Ca、Ti 和 Mn 的复杂尘埃消耗模式表明

• DOI: 10.1051/0004-6361/201730984
• 发表时间: 2018
• 期刊: Astronomy and Astrophysics
• 影响因子: 6.5
• 作者: Richter

Dust depletion of Ca and Ti in QSO absorption line systems

QSO 吸收线系统中 Ca 和 Ti 的粉尘去除

• DOI: 10.1051/0004-6361/201628466
• 发表时间: 2017
• 期刊: arXiv: Astrophysics of Galaxies
• 作者: Guber C. ;Richter P.
• 通讯作者: Richter P.