Woodrum Charity, Rieke Marcia, Ji Zhiyuan, Baker William M, Bhatawdekar Rachana, Bunker Andrew J, Charlot Stéphane, Curtis-Lake Emma, Eisenstein Daniel J, Hainline Kevin, Hausen Ryan, Helton Jakob M, Hviding Raphael E, Johnson Benjamin D, Robertson Brant, Sun Fengwu, Tacchella Sandro, Whitler Lily, Williams Christina C, Willmer Christopher N A
Steward Observatory, University of Arizona, Tucson, AZ 85721.
Kavli Institute for Cosmology, University of Cambridge, Cambridge CB3 0HA, United Kingdom.
Proc Natl Acad Sci U S A. 2024 Oct 15;121(42):e2317375121. doi: 10.1073/pnas.2317375121. Epub 2024 Oct 8.
The detection of numerous and relatively bright galaxies at redshifts > 9 has prompted new investigations into the star-forming properties of high-redshift galaxies. Using local forms of the initial mass function (IMF) to estimate stellar masses of these galaxies from their light output leads to galaxy masses that are at the limit allowed for the state of the Lambda Cold Dark Matter (ΛCDM) Universe at their redshift. We explore how varying the IMF assumed in studies of galaxies in the early universe changes the inferred values for the stellar masses of these galaxies. We infer galaxy properties with the spectral energy distribution (SED) fitting code Prospector using varying IMF parameterizations for a sample of 102 galaxies with photometry from the James Webb Space Telescope, JWST Advanced Deep Extragalactic Survey that are spectroscopically confirmed to be at [Formula: see text], with additional photometry from the JWST Extragalactic Medium Band Survey for twenty-one of the galaxies. We demonstrate that models with stellar masses reduced by a factor of three or more do not affect the modeled SED.
在红移大于9时探测到大量且相对明亮的星系,这促使人们对高红移星系的恒星形成特性展开新的研究。使用初始质量函数(IMF)的局部形式,根据这些星系的光输出估算其恒星质量,会得出在其红移时处于Lambda冷暗物质(ΛCDM)宇宙状态所允许极限的星系质量。我们探讨了在早期宇宙星系研究中假设的IMF变化如何改变这些星系恒星质量的推断值。我们使用光谱能量分布(SED)拟合代码Prospector,针对102个星系的样本,采用不同的IMF参数化方法来推断星系属性,这些星系来自詹姆斯·韦布空间望远镜(JWST)的高级深度河外巡天的测光数据,经光谱确认处于[公式:见正文],其中21个星系还有来自JWST河外中带巡天的额外测光数据。我们证明,恒星质量降低三倍或更多的模型不会影响所模拟的SED。