Ia 型超新星是重要的宇宙學距離指標，然而其前身星通道與爆炸機制至今 仍未被完全理解。為了對此進行限制，我們透過分析其宿主星系的性質，推測 有關前身星的重要資訊。本研究使用 ePESSTO+ 計畫於 2019 至 2023 年間所 觀測的 SNe Ia 最大光度時的光譜，探討 Si II λ6355 與 Si II λ5972 吸收線的 外殼膨脹速度及偽等效寬(pseudo equivalent width)與宿主星系物理性質(包 含恆星質量與比恆星形成率)之間的關係。我們同時比較不同的 SNe Ia 分類 方式與其宿主環境的相關性。結果顯示，傳統的分類在宿主星系性質上呈現出 最明顯的差異。此外，普通型 SNe Ia 可依宿主環境再區分為兩個亞型，可能 對應於不同的爆炸機制。對這些分類而言，Si II λ6355 吸收線的偽等效寬可作 為區分爆炸機制的良好指標。;Type Ia supernovae (SNe Ia) are important cosmological distance indicators; however, their progenitor channels and explosion mechanisms are not fully un- derstood. To constrain these aspects, we analyze the properties of their host galaxies, from which key information about the progenitors can be inferred. In this study, we examine the maximum-light spectra of SNe Ia obtained by the ePESSTO+ program from year 2019 to 2023. We investigate the relationships between the ejecta velocities and pseudo-equivalent widths (pEWs) of the Si II λ6355 and Si II λ5972 absorption lines and the physical properties of their host galaxies, including stellar mass and specific star formation rate. We also test how different SN Ia classification schemes correlate with their host environments. Our results show that the traditional subtype classification provides the clearest distinctions among host properties. Furthermore, normal SNe Ia can be divided into two subgroups based on their host environments, with one subgroup tend- ing to be High-Velocity (HV) and associated with older host galaxies, while the other tends to be Normal-Velocity (NV). For these subgroups, the pEW of the Si II λ6355 line serves as a strong indicator for distinguishing between their explo- sion mechanisms. These results suggest that 91bg-like SNe Ia and HV SNe Ia tend to favor double-degenerate progenitor systems.
