Abstract

We investigate the ionization sources of the diffuse gas at various galactic heights in galaxies with various stellar masses, H\(\alpha\) luminosities, and specific star formation rates. For this purpose, we use the SDSS-IV MaNGA DR16 data and the theoretical models of photoionization and shock ionization from the Mexican Million Models database (3MdB). Our final sample contains 239 edge-on galaxies, which makes the results statistically significant and allows even great galactic heights to be investigated using the spectra stacking procedure. Using diagnostic diagrams, we show that for galaxies of all the types being investigated the behavior of the diffuse ionized gas is adequately described by the models of photoionization by young OB stars and hot low-mass evolved stars. However, in galaxies with high stellar masses or passive star formation shocks can also contribute to the ionization. For galaxies of all the types being investigated we find that the flux from OB stars and the ionization parameter decrease with height, while the relative contribution of hot low-mass evolved stars to the ionization increases. The greatest difference of the contributions from these sources to the gas ionization is observed between galaxies with different specific star formation rates and different stellar masses: hot low-mass evolved stars are the main source of gas ionization in galaxies with passive star formation (and with high stellar masses), whereas in galaxies with active star formation (and with lower stellar masses) OB stars are a decisive factor of the diffuse gas ionization.

中文翻译：

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SDSS-IV ManNGA：平面外扩散电离气体的电离源

摘要

我们研究了具有不同恒星质量的星系中不同星系高度的扩散气体的电离源，H \(\alpha\)光度和特定的恒星形成率。为此，我们使用 SDSS-IV MaNGA DR16 数据以及来自墨西哥百万模型数据库 (3MdB) 的光电离和冲击电离理论模型。我们的最终样本包含 239 个边缘星系，这使得结果具有统计意义，并且甚至可以使用光谱叠加程序来研究很大的星系高度。使用诊断图，我们表明，对于所研究的所有类型的星系，年轻 OB 恒星和热低质量演化恒星的光电离模型充分描述了扩散电离气体的行为。然而，在具有高恒星质量或被动恒星形成冲击的星系中也可能有助于电离。对于所研究的所有类型的星系，我们发现OB恒星的通量和电离参数随着高度的增加而减小，而热的低质量演化恒星对电离的相对贡献则增加。这些来源对气体电离的贡献的最大差异是在具有不同特定恒星形成速率和不同恒星质量的星系之间观察到的：热的低质量演化恒星是具有被动恒星形成（并且具有被动恒星形成）的星系中气体电离的主要来源。高恒星质量），而在恒星形成活跃（以及恒星质量较低）的星系中，OB星是扩散气体电离的决定性因素。