Several highly luminous Type Ia supernovae (SNe?Ia) have been discovered. Their high luminosities are difficult to explain with the thermonuclear explosions of Chandrasekhar-mass white dwarfs (WDs). In the present study, we estimate the progenitor mass of SN 2009dc, one of the extremely luminous SNe?Ia, using the hydrodynamical models as follows. Explosion models of super-Chandrasekhar-mass (super-Ch-mass) WDs are constructed, and multi-color light curves (LCs) are calculated. The comparison between our calculations and the observations of SN 2009dc suggests that the exploding WD has a super-Ch mass of 2.2-2.4 M ☉, producing 1.2-1.4 M ☉ of 56Ni, if the extinction by its host galaxy is negligible. If the extinction is significant, the exploding WD is as massive as ~2.8 M ☉, and ~1.8 M ☉ of 56Ni is necessary to account for the observations. Whether the host-galaxy extinction is significant or not, the progenitor WD must have a thick carbon-oxygen layer in the outermost zone (20%-30% of the WD mass), which explains the observed low expansion velocity of the ejecta and the presence of carbon. Our estimate of the mass of the progenitor WD, especially for the extinction-corrected case, is challenging to the current scenarios of SNe?Ia. Implications for the progenitor scenarios are also discussed.
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机译：已经发现了几个高度发光的Ia型超新星（SNe？Ia）。它们的高发光度很难用钱德拉塞卡尔质量白矮星（WD）的热核爆炸来解释。在本研究中，我们使用以下流体力学模型来估计SN 2009dc的祖细胞质量，SN 2009dc是极发光的SNe？Ia之一。建立了超Chandrasekhar质量（super-Ch-mass）WD的爆炸模型，并计算了多色光曲线（LC）。我们的计算结果与SN 2009dc观测值之间的比较表明，爆炸的WD具有2.2-2.4 M super的超Ch质量，如果其主星系的灭绝可忽略不计，则产生1.2-1.4 M☉的56Ni。如果消光作用很大，则爆炸的WD会达到〜2.8 M massive的质量，因此需要约〜1.8 M☉的56Ni来说明观测结果。无论主体星系的灭绝是否显着，祖先WD必须在最外层具有厚的碳氧层（占WD质量的20％-30％），这解释了观察到的低喷射速度和顶空膨胀。碳的存在。我们对祖先WD的质量的估计，特别是对于消光校正的情况，对当前的SNe？Ia情景提出了挑战。还讨论了对祖先场景的影响。
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