AI 中文总结
研究大质量分子气团破碎成致密核心时核心质量分布的演化,通过分析ALMAGAL巡天数据,发现最大质量核心占总质量约38%且无系统趋势,基尼系数随核心总质量和演化阶段增加,揭示核心间质量不平等随气团演化而增长。
AI 中文摘要
大质量分子气团破碎成致密核心为星团设定了初始条件,但核心质量分布如何演化仍不清楚。利用ALMAGAL巡天(1013个气团和6348个核心),我们分析了514个至少包含四个核心($N_{\rm frag} \ge 4$)的气团中核心质量分布的基尼系数,这些气团总共包含5728个核心。我们发现,最大质量的核心始终占核心总质量的约38%($f_{\rm core,max} \approx 0.38$),与每个气团的核心总质量$M_{\rm core,tot}$没有系统趋势。基尼系数随核心总质量($M_{\rm core,tot}$,$r = 0.55$)和演化阶段($L/M$,$r = 0.38$)增加。$L/M > 6.0$的气团的基尼值(中位数0.62)明显高于$L/M \le 6.0$的气团(中位数0.49;$p = 4.23\times10^{-15}$)。这些结果表明,虽然最大质量核心的质量分数是恒定的,但随着气团演化,核心之间的整体质量不平等会系统性增加。
英文摘要
The fragmentation of massive molecular clumps into dense cores sets the initial conditions for stellar clusters, yet how core mass distributions evolve remains unclear. Using the ALMAGAL survey (1,013 clumps and 6,348 cores), we analyze the Gini coefficient of core mass distributions for the 514 clumps containing at least four cores ($N_{\rm frag} \ge 4$), which host 5,728 cores in total. We find that the most massive core consistently accounts for $\sim 38\%$ of the total core mass ($f_{\rm core,max} \approx 0.38$), with no systematic trend with the total mass of the core per clump $M_{\rm core,tot}$. The Gini coefficient increases with total core mass ($M_{\rm core,tot}$, $r=0.55$) and evolutionary stage ($L/M$, $r=0.38$). Clumps with $L/M > 6.0$ have significantly higher Gini values (median $0.62$) than those with $L/M \le 6.0$ (median $0.49$; $p = 4.23\times10^{-15}$). These results demonstrate that while the mass fraction of the most massive core is constant, overall mass inequality among cores grows systematically as clumps evolve.
Comments11 pages, 9 figures, accepted for publication in ApJ