AI 中文总结
研究通过积分场光谱学探索星系盘晕界面，发现线发射径向分布在特定半径转折，大半径处通量与恒星形成率相关，电离光子逃逸致观测通量，不同模型预测有分歧，凸显CGM发射线测量对区分模型的重要性。
AI 中文摘要
利用积分场光谱学，我们通过构建和分析一个包含72个正常、低红移星系的大样本的发射线图谱，来探索单个星系的盘晕界面或内星系晕介质（CGM）。这些星系的恒星质量跨越三个数量级，恒星形成率跨越四个数量级。我们发现Hα、[O II]和[O III]线发射径向分布在(1 - 2)R_e处出现陡峭转折。在此半径之外，随着中心星系恒星形成率降低，线发射径向分布的斜率变缓，这可能反映了反馈过程的强度。大半径处的线发射通量与星系的恒星形成率相关，但与恒星质量无关。这些发现表明，从中心星系恒星形成区域逃逸的电离光子导致了内CGM观测到的发射线通量，逃逸率可从[O III]和[O II]的比率推断。不同的理论模型对冷气体与中心星系恒星形成率的预测依赖关系存在分歧，凸显了CGM发射线测量对于区分不同恒星形成和反馈过程子网格模型的重要性。
英文摘要
Using integral field spectroscopy, we explore the disk-halo interface, or the inner circumgalactic medium (CGM), of individual galaxies by constructing and analyzing emission-line maps for a large sample (72) of normal, low-redshift galaxies spanning three orders of magnitude in stellar mass and four orders in star formation rate (SFR). We find a steep turnover occurring at $(1-2) R_e$ in the H$α$, [O {\small II}], and [O {\small III}] line emission radial profiles. Beyond this radius, the slope of the line emission radial profiles becomes shallower as the SFR of the central galaxy decreases, which might reflect the strength of the feedback processes. The line emission fluxes at large radius ($(5-10) R_e$ or $\sim (0.1-0.25)r_{\rm vir}$) correlate with the galaxy's SFR, but not with its stellar mass. These findings suggest that ionizing photons escaping from star-forming regions in the central galaxy account for the observed emission line fluxes from the inner CGM, with escape fractions inferred from the [O {\small III}] and [O {\small II}] ratio. Different state-of-the-art theoretical models do not agree on the predicted dependence of cool gas on the SFR of the central galaxies, highlighting the importance of CGM emission line measurements to distinguish between different subgrid models for star formation and feedback processes.
CommentsAccept for publication in Science Advances, Figure 1, 2, 3 are the main results
