论文标题
在NGC 6946中检测SN 2017EAW的晚期间隔互动
Detection of Late-Time Circumstellar Interaction of SN 2017eaw in NGC 6946
论文作者
论文摘要
SN 2017AW是NGC 6946中观察到的第十个超新星，是正常的II型超级nova，估计为11-13 MSUN Supergiant祖细胞。在这里，我们介绍了SN 2017AW的NEBULAR相光谱，在+545和+900天后，在MAX后+900天，延长了先前发表的光谱时期的大约50-400天。尽管+545天的光谱与在+400天到+493天之间拍摄的光谱相似，但+900天光谱在光谱特征和发射线轮廓上都显示出巨大的变化。 HALPHA发射是平坦的，盒子状的，鲜蓝色和红色轮廓速度约为-8000和+7500 km/s。这些后期光谱的变化表明与大量损坏的外壳相互作用很强，在爆炸前约1700年被驱逐约1700年。 SN 2017EW的+900天频谱与SN 2004et和SN 2013EJ在爆炸后2 - 3年观察到的频谱相似。我们讨论了对亮度SNE II-P的延迟监测的重要性以及SN II-P进化的Supernova群众群众事件的性质。
SN 2017eaw, the tenth supernova observed in NGC 6946, was a normal Type II-P supernova with an estimated 11 - 13 Msun supergiant progenitor. Here we present nebular phase spectra of SN 2017eaw at +545 and +900 days post-max, extending approximately 50 - 400 days past the epochs of previously published spectra. While the +545 day spectra is similar to spectra taken between days +400 and +493, the +900 day spectrum shows dramatic changes both in spectral features and emission line profiles. The Halpha emission is flat-topped and box-like with sharp blue and red profile velocities of ~ -8000 and +7500 km/s. These late-time spectral changes indicate strong circumstellar interaction with a mass-loss shell, expelled ~ 1700 years before explosion. SN 2017eaw's +900 day spectrum is similar to those seen for SN 2004et and SN 2013ej observed 2 - 3 years after explosion. We discuss the importance of late-time monitoring of bright SNe II-P and the nature of pre-supernova mass-loss events for SN II-P evolution.
