标题： 多环芳烃，异常微波辐射，以及它们与冷中性介质的联系 显示英文标题

标题： Polycyclic Aromatic Hydrocarbons, the Anomalous Microwave Emission, and Their Connection to the Cold Neutral Medium

摘要： 使用新的大区域冷中性介质（CNM）比例图，$f_{\rm CNM}$，我们研究了CNM、多环芳烃（PAHs）的丰度和异常微波辐射（AME）之间的关系。 我们首先展示了基于全天HI4PI数据的$f_{\rm CNM}$图，使用卷积神经网络将光谱HI数据转换为$f_{\rm CNM}$。 我们证明$f_{\rm CNM}$与从中红外和远红外尘埃辐射估计的PAHs中尘埃的比例强烈相关。 相反，我们发现$f_{\rm CNM}$与每单位尘埃辐射的AME量之间没有相关性，也发现$f_{\rm CNM}$与AME峰值频率之间没有相关性。 这些结果表明PAHs优先存在于冷且相对致密的气体中，可能是由于在更稀薄的介质中增强了破坏作用。 $f_{\rm CNM}$与AME峰值频率之间缺乏相关性与理论模型的预期相矛盾，这些模型假设冷中性介质和暖中性介质中的AME光谱能量分布不同。 我们建议，不同星际环境中PAH的丰度和发射物理可能解释了12$\mu$m PAH发射与AME之间弱于预期的相关性，即使PAH是AME的载体。 显示英文摘要

摘要： Using new large area maps of the cold neutral medium (CNM) fraction, $f_{\rm CNM}$, we investigate the relationship between the CNM, the abundance of polycyclic aromatic hydrocarbons (PAHs), and the anomalous microwave emission (AME). We first present our $f_{\rm CNM}$ map based on full-sky HI4PI data, using a convolutional neural network to covert the spectroscopic HI data to $f_{\rm CNM}$. We demonstrate that $f_{\rm CNM}$ is strongly correlated with the fraction of dust in PAHs as estimated from mid- and far-infrared dust emission. In contrast, we find no correlation between $f_{\rm CNM}$ and the amount of AME per dust emission, nor between $f_{\rm CNM}$ and the AME peak frequency. These results suggest PAHs preferentially reside in cold, relatively dense gas, perhaps owing to enhanced destruction in more diffuse media. The lack of correlation between $f_{\rm CNM}$ and AME peak frequency is in tension with expectations from theoretical models positing different spectral energy distributions of AME in the cold versus warm neutral medium. We suggest that different PAH abundances and emission physics in different interstellar environments may explain the weaker than expected correlation between 12$\mu$m PAH emission and AME even if PAHs are the AME carriers.