Nature Astronomy ( IF 12.9 ) Pub Date : 2024-10-11 , DOI: 10.1038/s41550-024-02384-8 William M. Baker, Sandro Tacchella, Benjamin D. Johnson, Erica Nelson, Katherine A. Suess, Francesco D’Eugenio, Mirko Curti, Anna de Graaff, Zhiyuan Ji, Roberto Maiolino, Brant Robertson, Jan Scholtz, Stacey Alberts, Santiago Arribas, Kristan Boyett, Andrew J. Bunker, Stefano Carniani, Stephane Charlot, Zuyi Chen, Jacopo Chevallard, Emma Curtis-Lake, A. Lola Danhaive, Christa DeCoursey, Eiichi Egami, Daniel J. Eisenstein, Ryan Endsley, Ryan Hausen, Jakob M. Helton, Nimisha Kumari, Tobias J. Looser, Michael V. Maseda, Dávid Puskás, Marcia Rieke, Lester Sandles, Fengwu Sun, Hannah Übler, Christina C. Williams, Christopher N. A. Willmer, Joris Witstok
The physical processes that establish the morphological evolution and the structural diversity of galaxies are key unknowns in extragalactic astrophysics. Here we report the finding of the morphologically mature galaxy JADES-GS+53.18343−27.79097, which existed within the first 700 million years of the Universe’s history. This star-forming galaxy with a stellar mass of 400 million solar masses consists of three components: a highly compact core with a half-light radius of less than 100 pc, an actively star-forming disc with a radius of about 400 pc and a star-forming clump, all of which show distinctive star-formation histories. The central stellar mass density of this galaxy is within a factor of 2 of the most massive present-day ellipticals, while being globally 1,000 times less massive. The radial profile of the specific star-formation rate is rising towards the outskirts. This evidence suggests a detection of the inside-out growth of a galaxy as a proto-bulge and a star-forming disc in the epoch of reionization.
中文翻译:
恒星形成盘中的一个核心,作为早期宇宙中由内而外生长的证据
建立星系形态演化和结构多样性的物理过程是银河系外天体物理学中的关键未知数。在这里,我们报告了形态成熟的星系 JADES-GS+53.18343−27.79097 的发现,它存在于宇宙历史的前 7 亿年中。这个恒星质量为 4 亿太阳质量的恒星形成星系由三个部分组成:一个半光半径小于 100 pc 的高度致密的核心、一个半径约为 400 pc 的活跃恒星形成盘和一个恒星形成团块,所有这些都显示出独特的恒星形成历史。这个星系的中心恒星质量密度是当今质量最大的椭圆星系的 2 倍以内,而全球质量却小了 1000 倍。特定恒星形成速率的径向剖面正在向外围上升。这一证据表明,在再电离时代,检测到了一个星系由内而外的增长,即原始凸起和恒星形成盘。