| Summary: | 碩士 === 國立中央大學 === 天文研究所 === 107 === We study runaway stars in the superbubble N160, supernova remnants (SNRs) N9 and N63A in the Large Magellanic Cloud (LMC). A runaway star in the superbubble N160 was diagnosed from its long-slit spectrum. A bow-shock-like structure was observed near this runaway. Assuming ram pressure equilibrium, the Hα surface brightness and the [S II] λ6716/λ6731 ratio gave the mass-loss rate not larger than 1.1±0.5×10−5M⊙/yr.
Gaia DR2 data were used to examine proper motions of massive stars in SNRs N9 and N63A to search for runaway stars as candidates for companions of their supernova progenitors. There is one star in N9 whose proper motion is large considered as the runaway star. However, the environment is so complex that it needs better observational data to confirm its natures. In the case of N63A, an eclipsing binary showed high proper motion. More observations and models are needed to explain the high proper motions of this binary and whether they are runaway companions or not in the future. We also noticed that some stars with large proper motion are actually unresolved multiple stars. The large proper motions of these stars are most likely spurious. Therefore, we note the importance of checking high-resolution images In summary, we diagnosed three runaway stars/binary that could be candidates for companions of SN progenitors in the LMC.
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