arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0710.4146astro-ph
收藏

高红移星系的恒星形成、气体流动和化学演化模型

A Model for Star Formation, Gas Flows and Chemical Evolution in Galaxies at High Redshifts

Dawn K. Erb

摘要:

由于越来越多地使用Kennicutt-Schmidt(K-S)恒星形成定律来解释高红移星系的观测,气体吸积对星系形成的重要性,以及最近对z~2 - 3星系中化学丰度的观测,我使用简单的分析模型来评估这些星系演化过程与观测的一致性以及它们之间的一致性。导出了K-S定律所隐含的恒星形成的时间依赖关系,并指出在z~2 - 3处观测到的恒星形成速率的持续高值需要额外的气体吸积。一个模型中,气体吸积率约等于合并的恒星形成和流出率广泛复制观察到的趋势,恒星形成率与星系年龄。使用的化学演化的分析描述,我还表明,这个模型,进一步限制有一个流出率大致等于恒星形成率,再现所观察到的质量金属丰度关系在z~2。

英文摘要:

Motivated by the increasing use of the Kennicutt-Schmidt (K-S) star formation law to interpret observations of high redshift galaxies, the importance of gas accretion to galaxy formation, and the recent observations of chemical abundances in galaxies at z~2-3, I use simple analytical models to assess the consistency of these processes of galaxy evolution with observations and with each other. I derive the time dependence of star formation implied by the K-S law, and show that the sustained high star formation rates observed in galaxies at z~2-3 require the accretion of additional gas. A model in which the gas accretion rate is approximately equal to the combined star formation and outflow rates broadly reproduces the observed trends of star formation rate with galaxy age. Using an analytical description of chemical evolution, I also show that this model, further constrained to have an outflow rate roughly equal to the star formation rate, reproduces the observed mass-metallicity relation at z~2.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑