论文标题
在M33中搜索以Balmer为主的IA Supernova遗迹
Searching for Balmer-dominated Type Ia Supernova Remnants in M33
论文作者
论文摘要
我们已经通过选择$ l _ {\ rm x} \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ ge 5 \ e ergs s $^{ - 1} $，搜索了M33中的IA SNRS类型。我们的搜索在M33中没有发现任何以Balmer为主的IA SNRS。这个结果令人困惑，因为M33的质量是LMC的2-3倍，但LMC托有五个Balmer主导的IA SNR型，M33没有。我们已经考虑了观察性偏差，星际密度和电离条件，恒星形成历史记录和IA SN型延迟时间分布函数的IA型SN率以及金属性效应。这些都无法解释M33中X射线亮型Balmer型IA SNR的缺失。令人着迷的是，银河系具有X射线蓝色和热型IA SNR（Kepler和Tycho）以及X射线型和非热的IA型SNR（G1.9+0.3，SN1006和RCW86），而LMC则没有X-Ray-and and X-Ray-and和Mytral和M33 deft and therm and and k33 deft and k33 are and and k33 are and k33 are and k33 areyt and k33 are the them and k33 are and k33 are and k33 are and k33。
We have searched for Balmer-dominated Type Ia SNRs in M33 by selecting thermal X-ray sources with $L_{\rm X} \ge 5\times10^{35}$ ergs s$^{-1}$, identifying associated H$α$ emission features, and checking their [S II] and [O III] emission properties. Our search did not find any Balmer-dominated Type Ia SNRs in M33. This result is puzzling because M33 is 2-3 times more massive than the LMC, yet the LMC hosts five Balmer-dominated Type Ia SNRs and M33 has none. We have considered observational biases, interstellar densities and ionization conditions, Type Ia SN rate expected from the star formation history and Type Ia SN delay time distribution function, and metallicity effect. None of these can explain the absence of X-ray-bright Balmer-dominated Type Ia SNRs in M33. It is intriguing that the Galaxy has X-ray-bright and thermal Type Ia SNRs (Kepler and Tycho) as well as X-ray-faint and nonthermal Type Ia SNRs (G1.9+0.3, SN1006, and RCW86), while the LMC does not have the X-ray-faint and nonthermal ones and M33 does not have the X-ray-bright and thermal ones.
