论文标题
测量Pan-Starrs1中等深度调查的IA型超新星的弹射速度
Measuring the Ejecta Velocities of Type Ia Supernovae from the Pan-STARRS1 Medium Deep Survey
论文作者
论文摘要
越来越多的证据表明，IA型超新星（SNE IA）可能起源于多个爆炸通道。先前的研究表明，SNE IA的射速速度是区分不同通道的强大工具。在这项工作中，我们研究了pan-Starrs1中等深度调查（PS1-MDS）发现的〜400个确认的SNE IA，并获得了〜50 sne IA的样本，该样品具有接近峰值SI II 6355速度（VSI）测量值。我们研究了VSI和各种参数之间的关系，包括SN灯曲线宽度，颜色，宿主 - 盖亚特性和红移。 VSI和光曲线参数之间未发现明显的趋势。关于宿主 - 甘马的特性，我们看到了一个重大趋势，即与正常速度（NV）IA（VSI <12000 km/s）相比，高速（HV）SNE IA（VSI> 12000 km/s）倾向于驻留在更大的星系中，而在结合PS1-MDS数据集和以前的Low-Z研究时。尽管我们没有看到VSI和RedShift之间的显着趋势，但在低Z样品中，HV SNE IA似乎比在高Z样品中更为普遍。我们讨论了有可能导致这一趋势的几种可能性。此外，我们研究了SN IA距离的潜在偏差，并且发现HV和NV亚组之间的哈勃残差没有显着差异。
There is growing evidence that Type Ia supernovae (SNe Ia) may originate from multiple explosion channels. Previous studies have indicated that the ejecta velocity of SNe Ia is one powerful tool to discriminate between different channels. In this work, we study ~400 confirmed SNe Ia discovered by the Pan-STARRS1 Medium Deep Survey (PS1-MDS), and obtain a sample of ~50 SNe Ia that have near-peak Si II 6355 velocity (Vsi) measurements. We investigate the relationships between Vsi and various parameters, including SN light-curve width, color, host-galaxy properties, and redshift. No significant trends are identified between Vsi and light-curve parameters. Regarding the host-galaxy properties, we see a significant trend that high-velocity (HV) SNe Ia (Vsi > 12000 km/s) tend to reside in more massive galaxies compared to normal-velocity (NV) SNe Ia (Vsi < 12000 km/s) when combining both the PS1-MDS dataset and those from previous low-z studies. While we do not see a significant trend between Vsi and redshift, HV SNe Ia appear to be more prevalent in low-z samples than in high-z samples. We discuss several possibilities that could potentially contribute to this trend. Furthermore, we investigate the potential bias on SN Ia distances and find no significant difference in Hubble residuals between HV and NV subgroups.
