论文标题
SN 2021FOA，类型IIN（SN 2009IP）与IBN类型超新星之间的过渡事件
SN 2021foa, a transitional event between a Type IIn (SN 2009ip-like) and a Type Ibn supernova
论文作者
论文摘要
我们提供了异常相互作用的超新星（SN）2021FOA的光度和光谱数据。它在20天内上升至$ m_r = -18 $ mag的绝对幅度峰值。初始光曲线下降显示在长期变平之前，会显示一些光度波动。在主要事件之前的几周内检测到一个微弱的来源（$ M_R \ sim -14 $ mag），显示出缓慢的发光趋势。 $ r $ - 带绝对光曲线与SN 2009IP式事件非常相似，持续时间变亮（``event a''），然后是更明亮的峰（``event b''。 Sn 2021foa的早期光谱显示出蓝色的连续体（$ v_ {fwhm} \ sim $ 400 km s $ s $^{ - 1} $）h排放线，两周后，揭示了一个复杂的轮廓，露出一个狭窄的p cygni，在中间宽度（$ v_ $ vwhm} $ 2700 km $ 2700 km $ 2700 km $ vhimediaptiage the tof the tof the the in MiddeDiaptiaDthi。在+12天的发射中，出现了金属线，而\ hei线变得非常强，\ hei〜 $λ$ 5876达到\ ha光度的一半，比以前的SN 2009IP样品高得多。我们建议SN 2021FOA是H-Rich SN 2009IP SNE和HE-HE-HE-HE-HE型IBN SNE之间的过渡事件。
We present photometric and spectroscopic data of the unusual interacting supernova (SN) 2021foa. It rose to an absolute magnitude peak of $M_r=-18$ mag in 20 days. The initial light curve decline shows some luminosity fluctuations before a long-lasting flattening. A faint source ($M_r\sim -14$ mag) was detected in the weeks preceding the main event, showing a slow-rising luminosity trend. The $r$-band absolute light curve is very similar to those of SN 2009ip-like events, with a faint and shorter duration brightening (`Event A') followed by a much brighter peak (`Event B'). The early spectra of SN 2021foa show a blue continuum with narrow ($v_{FWHM}\sim$400 km s$^{-1}$) H emission lines, that, two weeks later, reveal a complex profile, with a narrow P Cygni on top of an intermediate-width ($v_{FWHM}\sim$2700 km s$^{-1}$) component. At +12 days metal lines in emission appear, while \Hei lines become very strong, with \Hei~$λ$5876 reaching half of the \Ha luminosity, much higher than in previous SN 2009ip-like objects. We propose SN 2021foa to be a transitional event between the H-rich SN 2009ip-like SNe and the He-rich Type Ibn SNe.
