The temperatures of the plasma in supernova remnants (SNRs) are initially very low just after the shock heating. The electron temperature (kTe) increases quickly by Coulomb interaction, and then the energetic electrons gradually ionize atoms to increase the ionization temperature (kTi). The observational fact is that most young and middle-to-old SNRs have lower kTi than kTe after the shock heating. The temperature evolution in shell-like SNRs has been explained by this ionizing plasma (IP) scenario. On the other hand, in the last decade, a significant fraction of mixed-morphology SNRs was found to exhibit a recombining plasma (RP) with higher kTi than kTe. The origin and the evolution mechanism of RP SNRs have been puzzling. To address this puzzle, this paper presents kTe and kTi profiles using follow-up Suzaku observations, and then proposes a new scenario for the temperature and morphology evolution in IP and RP SNRs.

中文翻译：

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超新星遗迹中电离和重组等离子体之间电离温度的系统比较

超新星遗迹 (SNR) 中等离子体的温度在冲击加热后最初非常低。由于库仑相互作用，电子温度（kTe）迅速升高，然后高能电子逐渐电离原子以提高电离温度（kTi）。观察到的事实是，大多数年轻和中老年 SNR 在冲击加热后的 kTi 低于 kTe。这种电离等离子体 (IP) 情景已经解释了壳状 SNR 中的温度演变。另一方面，在过去十年中，发现很大一部分混合形态 SNR 表现出具有比 kTe 更高的 kTi 的重组等离子体 (RP)。RP SNR的起源和演化机制一直令人费解。为了解决这个难题，本文使用后续的 Suzaku 观察来介绍 kTe 和 kTi 剖面，