论文标题
两个带有偶然性互动的剥离信封超新星 - 但只有一个真正显示了
Two stripped envelope supernovae with circumstellar interaction -- but only one really shows it
论文作者
论文摘要
我们提出SN 2019TSF（ZTF19ACKJSZS）和SN 2019OYS（ZTF19ABUCWZT）。这两个剥离的信封型IB超新星突然在其晚光曲线中显示出（重新）变亮。我们在与先前发射的材料的相互作用（CSM）相互作用的背景下进行了研究，这是一种在SENNE中不寻常的现象。我们分析了由光光曲线和光谱组成的观察数据。对于SN 2019oys，我们还可以在广播中进行检测以及紫外线和X射线的限制。两条光曲线在大约100天后均显示出壮观的重新夸张。在SN 2019TSF的情况下，重新亮相之后是一个新的下降时期，并且光谱从未显示出狭窄的发射线的迹象，这些迹象表明CSM相互作用。相反，SN 2019oys从类型的Ib进行了光谱改造，从光曲线亮阶段的CSM相互作用显然主导的光谱。深光谱揭示了许多狭窄的高电离线，包括冠状线，无线电观察结果显示出强大的发射。相当相似的光曲线行为表明CSM相互作用与动力源。对于SN 2019，证据表明，射流击中富含H的富含H的材料（可能是从祖细胞之星弹出）是显而易见的。我们观察到H和HE的狭窄线，但也有许多高电离线，包括冠状线，揭示了冲击相互作用。 SN 2019oys的光谱模拟显示了两个不同的密度成分，一个密度> 1E9 /cm3，由H I，He I，Na I和Ca II的较宽，低电离线占主导地位，另一个在约1e6 /cm3的密度下具有狭窄的高电离线。前者受电子散射的强烈影响。 SN 2019oys中CSM相互作用的证据通过无线电检测证实。相反，对于SN 2019TSF，我们在光谱中几乎没有证据表明任何CSM相互作用。
We present SN 2019tsf (ZTF19ackjszs) and SN 2019oys (ZTF19abucwzt). These two stripped envelope Type Ib supernovae suddenly showed a (re-)brightening in their late light curves. We investigate this in the context of circumstellar material (CSM) interaction with previously ejected material, a phenomenon that is unusual among SE SNe. We analyse observational data, consisting of optical light curves and spectra. For SN 2019oys we also have detections in radio as well as limits from UV and X-rays. Both light curves show spectacular re-brightening after about 100 days. In the case of SN 2019tsf, the re-brightening is followed by a new period of decline, and the spectra never show signs of narrow emission lines that would indicate CSM interaction. On the contrary, SN 2019oys made a spectral makeover from a Type Ib to a spectrum clearly dominated by CSM interaction at the light curve brightening phase. Deep spectra reveal a plethora of narrow high ionization lines, including coronal lines, and the radio observations show strong emission. The rather similar light curve behaviour indicate CSM interaction as the powering source. For SN 2019oys the evidence for a phase where the ejecta hit H-rich material, likely ejected from the progenitor star, is conspicuous. We observe strong narrow lines of H and He, but also a plethora of high ionization lines, including coronal lines, revealing shock interaction. Spectral simulations of SN 2019oys show two distinct density components, one with density > 1e9/cm3, dominated by somewhat broader, low ionization lines of H I, He I, Na I and Ca II, and one with narrow, high ionization lines at a density about 1e6 /cm3. The former is strongly affected by electron scattering. The evidence for CSM interaction in SN 2019oys is corroborated by detections in radio. On the contrary, for SN 2019tsf, we find little evidence in the spectra for any CSM interaction.
