标题： 高红移活动星系核相关扩展气体星云中的电子能量分布：麦克斯韦-玻尔兹曼分布与kappa分布 显示英文标题

标题： Electron Energy Distributions in the Extended Gas Nebulae associated with High-z AGN: Maxwell-Boltzmann vs. kappa distributions

摘要： 电离线观测结合光致电离模型为AGN电离气体中的电离机制、密度、温度和金属丰度提供了重要的信息。光致电离模型通常假设麦克斯韦-玻尔兹曼（M-B）电子能量分布（EED），但有建议认为使用kappa分布可能更为合适，并且可能解决在HII区域和行星状星云（PNe）中发现的温度和丰度差异。我们考虑了在与AGN相关的光致电离星云中存在kappa分布的影响，并研究了这可能会如何影响这些区域的光谱建模和丰度分析。使用光致电离代码MAPPINGS 1e，我们计算了采用M-B和kappa分布的电子能量的模型，并比较了不同kappa值、气体金属丰度、密度、电离参数和SED斜率下发射线比率的行为。我们发现，EED的选择会对由与AGN相关的光致电离星云发出的一些紫外和光学发射线产生重大影响，而采用kappa分布的影响强烈依赖于气体金属丰度和电离参数。我们整理了一个包含143个类型2 AGN的线比率样本，并将我们的模型与观测到的线比率进行比较。我们发现，在98个天体中，kappa分布比M-B分布更能拟合观测到的线比率。此外，我们发现采用kappa分布的电子能量会导致显著改变在相当一部分天体中推导出的气体金属丰度和电离参数。 显示英文摘要

摘要： Emission line observations together with photoionization models provide important information about the ionization mechanisms, densities, temperatures, and metallicities in AGN-ionized gas. Photoionization models usually assume Maxwell-Boltzmann (M-B) electron energy distributions (EED), but it has been suggested that using kappa distributions may be more appropriate and could potentially solve the discrepancies in temperatures and abundances found in HII regions and Planetary Nebulae (PNe). We consider the impact of the presence of kappa distributions in photoionized nebulae associated with AGN and study how this might affect spectral modelling and abundance analyses for such regions. Using the photoionization code MAPPINGS 1e we compute models adopting M-B and kappa distributions of electron energies, and compare the behaviour of emission line ratios for different values of kappa, gas metallicity, density, ionization parameter and SED slope. We find that the choice of EED can have a large impact on some UV and optical emission lines emitted by photoionized nebulae associated with AGN, and that the impact of adopting a kappa distribution is strongly dependent on gas metallicity and ionization parameter. We compile a sample of line ratios for 143 type 2 AGN and compare our models against the observed line ratios. We find that for 98 objects kappa distributions provide a better fit to the observed line ratios than M-B distributions. In addition, we find that adopting kappa-distributed electron energies results in significant changes in the inferred gas metallicity and ionization parameter in a significant fraction of objects.