发表机构
Tsinghua University; The University of Tokyo（清华大学; 东京大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
AEON-z5是红移5.23的星系，JWST观测显示其双极外流将金属丰度接近太阳的气体输运至4千秒差距外的星系周介质，揭示早期活动星系核驱动金属循环的直接证据。
AI 中文摘要
化学增丰气体从星系向其周围环境的扩散是星系演化的关键过程，然而在红移z>5处直接观测证据仍然稀少。我们展示了AEON-z5，一个位于COSMOS场中红移z~5.23的星系，由一个紧凑的连续谱发射核心和周围延伸的、以谱线为主的电离星云组成。JWST/NIRCam成像显示，H$\alpha$+[N II]和H$\beta$+[O III]发射延伸至投影半径>4 kpc——是宿主恒星质量下典型有效半径的2-2.5倍——到达外部星际介质和内部星系周介质。F444W棱栅数据揭示了高度不对称的H$\alpha$+[N II]轮廓，我们将其解释为双极外流，并分解为三个运动学成分。主导成分的通量加权速度偏移约为+489 km/s，半高全宽~630 km/s，其翼部达到$v_{84}$~792 km/s。一个暂定的分离特征位于$\Delta v_{LOS}$~2800 km/s处，在1D光谱中以1.5$\sigma$探测到（2D拟合中为2.4$\sigma$），可能追踪一个外流团块。这些运动学特征最一致的解释是核心中存在活动星系核。对于延伸星云，我们推导出随半径红移的速度曲线，在$r_p$~1.3-2.5 kpc处达到200-400 km/s——这一趋势可能反映了加速的外流、共转气体或投影中看到的再循环入流。关键的是，测得的[N II]/H$\alpha$比值暗示接近太阳丰度的N2基丰度（0.7-1.0 $Z_\odot$），在考虑活动星系核激发和校准系统误差后仍保持>0.37 $Z_\odot$。大尺度延伸、增丰和极端运动学的结合将AEON-z5确定为反馈驱动金属输运的候选快照，提供了在宇宙最初约11亿年内早期活动星系核活动如何将化学处理气体重新分布到星系周介质的直接视角。
英文摘要
The dispersal of chemically enriched gas from galaxies into their surroundings is a key process in galaxy evolution, yet direct observational evidence at z>5 remains scarce. We present AEON-z5, a galaxy at z~5.23 in the COSMOS field comprising a compact continuum-emitting core surrounded by an extended, line-dominated ionized nebula. JWST/NIRCam imaging shows that H$α$+[N II] and H$β$+[O III] emission extends to projected radii of >4 kpc - 2-2.5 times the typical effective radius at the host stellar mass - reaching the outer ISM and the inner CGM. F444W grism data reveal a highly asymmetric H$α$+[N II] profile, which we interpret as a bipolar outflow and decompose into three kinematic components. The dominant component has a flux-weighted velocity offset of ~+489 km/s and FWHM~630 km/s, with a wing reaching $v_{84}$~792 km/s. A tentative detached feature at $Δv_{LOS}$~2800 km/s, detected at 1.5$σ$ in the 1D spectrum (2.4$σ$ in the 2D fit), may trace an outflow clump. These kinematics are most coherently explained by an AGN in the core. For the extended nebula, we derive a velocity curve shifting redward with radius, reaching 200-400 km/s at $r_p$~1.3-2.5 kpc - a trend that may reflect an accelerating outflow, corotating gas, or recycled inflow viewed in projection. Crucially, the measured [N II]/H$α$ ratios imply near-solar N2-based abundances (0.7-1.0 $Z_\odot$), remaining >0.37 $Z_\odot$ after allowing for AGN excitation and calibration systematics. The combination of large extent, enrichment, and extreme kinematics identifies AEON-z5 as a candidate snapshot of feedback-driven metal transport, offering a direct view of how early AGN activity may redistribute chemically processed gas into the CGM within the first ~1.1 billion years.
Comments20 pages, 8 figures
