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We propose a 200 ks XMM-Newton observation of the d_commaFe-richd_comma knot in the Type Ia supernova remnant of Kepler to confirm that the explosion originated from a near-Chandrasekhar-mass white dwarf openParWDclosePar. Previous observations by Chandra have revealed an Fe-rich ejecta knot within the SNR moving at nearly the free expansion speed. The current spectrum of the knot shows strong emission lines from Fe-peak elements openParCr comma Mn comma NiclosePar comma pointing to an origin in the deepest layer of a near-Chandrasekhar-mass WD. However comma due to high background in the Chandra data comma it is difficult to claim a significant detection of the Ni line comma which is key to determining the burning regime. Thanks to low background comma high sensitivity in the Ni band comma only the XMM-Newton can resolve this important issue in SN Ia physics.

我们提出对开普勒Ia型超新星遗迹内的富铁（Fe-rich）结开展200千秒（ks）的XMM-牛顿（XMM-Newton）观测，以证实此次爆炸起源于近钱德拉塞卡质量的白矮星（WD）。此前钱德拉（Chandra）的观测已在该超新星遗迹中发现了一个以接近自由膨胀速度运动的富铁抛射结。该结的当前能谱显示出铁峰元素（铬Cr、锰Mn、镍Ni）的强发射线，这表明其源自近钱德拉塞卡质量白矮星的最深层区域。然而，由于钱德拉观测数据存在较高背景，难以确凿地检测到镍线——而镍线正是确定燃烧机制的关键指标。得益于低背景环境与镍波段的高灵敏度，唯有XMM-牛顿望远镜能够解决Ia型超新星物理领域的这一重要问题。