发表机构
University of Hertfordshire; University of Manchester; University of Nottingham; University of Cambridge（赫特福德大学; 曼彻斯特大学; 诺丁汉大学; 剑桥大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用约13,000个星系的质量完备样本，发现星系形态与环境的关系随质量变化：大质量星系中早型星系更靠近节点和丝状结构，而低质量星系中形态差异减弱，表明演化由内部过程主导。
AI 中文摘要
我们首次利用一个质量完备的样本，研究了从大质量星系到矮星系中形态与环境之间的关系。该样本包含约13,000个星系，恒星质量范围为10^8太阳质量 < Mstar < 10^11.5太阳质量，红移范围为0.2<z<0.4。通过结合哈勃空间望远镜（HST）得出的视觉形态分类、局部密度以及星系到节点和丝状结构的距离，我们量化了早型星系（ETGs）和晚型星系（LTGs）在环境方面的差异。总体早型星系比例从Mstar ~ 10^11太阳质量时的约65%下降到Mstar ~ 10^8太阳质量时的约20%。无论形态如何，较低恒星质量的星系比质量更大的对应星系距离节点和丝状结构更远。在Mstar > 10^9太阳质量时，早型星系比晚型星系距离节点和丝状结构更远，但这种分离随着恒星质量的降低而减弱，在Mstar < 10^9太阳质量时，早型星系和晚型星系表现出相似的位置。在较低恒星质量下这种差异的减小可能源于丝状结构的有限范围，以及较低质量星系（无论形态如何）距离丝状结构核心更远，因此被限制在丝状结构本身更小的区域内。对于大质量星系（其中早型星系和晚型星系表现出强烈的环境分离），更靠近节点可能抑制了相干角动量的获取，而更靠近丝状结构核心则增加了相互作用和并合的可能性。这两者都更容易形成由弥散主导的系统，从而在靠近节点（以及较小程度上靠近丝状结构）的大质量区域推动早型星系比例的急剧上升。我们的结果表明，随着恒星质量的降低，星系演化越来越由内部过程驱动。
英文摘要
We study how morphology relates to environment from massive to dwarf galaxies using, for the first time, a mass-complete sample of ~13,000 galaxies, in the stellar-mass and redshift ranges 10^8 MSun < Mstar < 10^11.5 MSun and 0.2<z<0.4, respectively. By combining HST-derived visual morphological classifications with local density and galaxy distances from nodes and filaments, we quantify how early-type and late-type galaxies (ETGs and LTGs) differ with respect to environment. The overall ETG fraction decreases from ~65 per cent at Mstar ~ 10^11 MSun to ~20 per cent at Mstar ~ 10^8 MSun. Regardless of morphology, lower stellar mass galaxies lie further away from nodes and filaments than their more massive counterparts. While, at Mstar > 10^9 MSun, ETGs reside further away from nodes and filaments than LTGs, this segregation weakens as stellar mass decreases, with ETGs and LTGs exhibiting similar locations at Mstar < 10^9 MSun. This diminishing difference at lower stellar mass is likely driven by the fact that filaments have a finite extent and lower mass galaxies, of all morphologies, lie further away from filament cores and are therefore confined to a smaller region of the filament itself. For high-mass galaxies (where ETGs and LTGs show strong environmental segregation), greater proximity to nodes likely inhibits coherent angular momentum acquisition, while residing closer to filament cores increases the likelihood of interactions and mergers. Both make it easier to create dispersion-dominated systems, driving the sharp rise of the ETG fraction, in the high-mass regime, close to nodes (and, to a lesser extent) filaments. Our results show that galaxy evolution is increasingly driven by internal processes as stellar mass decreases.
CommentsAccepted for publication in MNRAS, 11 pages, 8 figures
