论文标题
SN 2019EWU：具有早期强碳和弱的氧气特征的奇特超新星，来自新样本的年轻SN IC光谱
SN 2019ewu: A Peculiar Supernova with Early Strong Carbon and Weak Oxygen Features from a New Sample of Young SN Ic Spectra
论文作者
论文摘要
随着高节奏的出现，全天的自动化调查，超新星（SNE）现在比以往任何时候都更接近他们的爆炸日期。然而，年轻的最大速度前的光线后续频谱（SNE IC）可能是由于剥离最多的巨星而引起的，尽管它们的重要性仍然很少。在本文中，我们介绍了一组49个光谱，该光谱是通过全球超新星项目观察到的6 sne IC，其中包括17个最大最大频谱，其中8个在V波段最大光前一周以上观察到了8个。该数据集将公开可获得的最大亮度SN IC光谱的总数增加25％，我们提供了公开可用的闪电模板，这些模板将大大有助于将来快速识别Young Sne IC。我们介绍了这些光谱的详细分析，包括FE II 5169速度测量，O I 7774线强度和连续形状。我们将结果与文献中发表的超新星的样本进行了比较，并在我们的样本中找到一个脱颖而出的SN。 SN 2019EWU具有SNIC的独特功能组合：非常蓝色的连续性，高吸收速度，P-Cygni形状的功能，在最大光线之前将近2周，TARDIS辐射传输模型属性属于C II而不是H $α$，而不是H $α$，以及弱或不存在的O I 7774吸收功能。
With the advent of high cadence, all-sky automated surveys, supernovae (SNe) are now discovered closer than ever to their dates of explosion. However, young pre-maximum light follow-up spectra of Type Ic supernovae (SNe Ic), probably arising from the most stripped massive stars, remain rare despite their importance. In this paper we present a set of 49 optical spectra observed with the Las Cumbres Observatory through the Global Supernova Project for 6 SNe Ic, including a total of 17 pre-maximum spectra, of which 8 are observed more than a week before V-band maximum light. This dataset increases the total number of publicly available pre-maximum light SN Ic spectra by 25% and we provide publicly available SNID templates that will significantly aid in the fast identification of young SNe Ic in the future. We present detailed analysis of these spectra, including Fe II 5169 velocity measurements, O I 7774 line strengths, and continuum shapes. We compare our results to published samples of stripped supernovae in the literature and find one SN in our sample that stands out. SN 2019ewu has a unique combination of features for a SN Ic: an extremely blue continuum, high absorption velocities, a P-cygni shaped feature almost 2 weeks before maximum light that TARDIS radiative transfer modeling attributes to C II rather than H$α$, and weak or non-existent O I 7774 absorption feature until maximum light.
