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We propose 10 yr post-explosion UV-optical imaging of the remarkable transient SN 2009ip comma in order to determine its ultimate fate. This object was discovered in a non-terminal eruption in 2009 comma and then appeared to explode in a much more extreme supernova (SN)-like event in 2012. A very massive (80 Msun) quiescent progenitor was identified in an archival HST image comma and the star had several luminous blue variable (LBV)-like eruptions before 2012. Many SNe IIn are inferred to have LBV progenitors to make their dense circumstellar material (CSM) comma but SN2009ip is an extraordinary case where the LBV-like progenitor was detected directly comma and where spectra of numerous pre-SN eruptions were obtained. No other SN has this treasure trove of detailed information about the progenitor (not even SN1987A). This was one of the most important transient events of the past decade comma because if it was a true core-collapse (CC) SN comma then it is the first definitive case of a very massive star above 30 Msun that went SN and didn.t collapse to a black hole. However comma the interpretation of SN2009ip as a true CCSN is controversial for 2 reasonsdoublePoint (1) its lightcurve could also be explained by shell collisions from non-terminal explosive transients comma and (2) the tell-tale signs of nucleosynthetic products comma if present comma were largely masked by CSM interaction. As with all SN progenitor candidates comma proof that the star is dead requires that it disappear in late time data. Five years ago the source was only marginally fainter than the progenitor and apparently still fading. Cycle 29 will be 10 years since explosion. Our proposed observations will determine once and for all if the progenitor is gone.

我们提议对显著暂现源SN 2009ip开展爆发后10年的紫外-光学成像观测，以确定其最终命运。该天体于2009年因一次非终结性爆发被发现，随后在2012年发生了一次更为剧烈的类超新星（SN）事件。在哈勃空间望远镜（HST）的存档图像中已识别出其大质量（80倍太阳质量）的宁静前身星，且该恒星在2012年前发生过多次类亮蓝变星（LBV）爆发。许多IIn型超新星被推断拥有亮蓝变星前身星，以产生其致密星周物质（CSM），但SN2009ip是一个特例——其类亮蓝变星前身星被直接探测到，且获得了多次爆发前活动的光谱。没有其他超新星拥有如此丰富的前身星详细信息宝库（即使是SN1987A也不例外）。这是过去十年中最重要的暂现事件之一，因为若它是一次真正的核坍缩（CC）超新星，则它将是首个确凿案例：一颗质量超过30倍太阳质量的大质量恒星发生超新星爆发后未坍缩为黑洞。然而，将SN2009ip解释为真正的核坍缩超新星存在两点争议：（1）其光变曲线也可由非终结性爆发暂现源的壳层碰撞解释；（2）核合成产物的特征迹象（若存在）在很大程度上被星周物质相互作用掩盖。与所有超新星前身星候选体一样，证明该恒星已死亡需要其在晚期数据中消失。五年前，该源仅比其前身星略微暗淡，且显然仍在变暗。第29个观测周期将是爆发后的第10年。我们提议的观测将一劳永逸地确定其前身星是否已消失。