论文标题
SN 2018HTI：附近的超浮肿超新星在金属贫困的星系中发现
SN 2018hti: a nearby superluminous supernova discovered in a metal-poor galaxy
论文作者
论文摘要
SN 2018HTI是I型超浮肿超新星（SLSN〜I），绝对$ g $ -b $ - 带的幅度为$ -22.2 $，最大亮度为$ -22.2 $，以0.0612的红移在金属贫困的星系中发现。我们介绍了该超新星的广泛光度和光谱观察结果，涵盖了$ \ sim -35 $的阶段，至$ r $ band最大值的+340天以上。将我们的$ bvgri $ -band光度法与{\ it swift} uvot光学/紫外线光度法相结合，我们将峰值发光度计算为$ \ sim 3.5 \ times10^{44} $ erg s $^{ - 1} $。对观察到的光曲线进行建模表明，SN 2018HTI的光度演变可以由5.8 $ M_ \ odot $的弹出质量和具有磁场为$ b = 1.8 \ times10^{13} $ 〜g的磁场的磁场产生，其初始旋转周期为$ p_0 = 1.8 $ ms。基于这种磁力供电的情况和更大的样品，可以推断出大多数SLSNE〜I的磁力旋转与射流能量之间的相关性，这表明是一种自持平的情况。像其他Slsne〜I一样，SN 2018HTI的主机Galaxy被发现相对较弱（$ M_ {G} = -17.75 $ mag）和低金属性（$ z = 0.3〜Z_ \ odot $），星形形成率为0.3 $ M_ \ odot $ yr $ yr $ $ yr $^{-1} $。根据单星发展的模拟结果，SN 2018HTI可能源自巨大的，贫穷的恒星，其零年龄主序列（ZAMS）质量为25--40 $ M_ \ odot $，或者来自不太庞大的旋转恒星，带有$ M_ \ mathrm {zams} \ yathrm {Zams} \ od-Mathrm {Zams} \ od-25 $ 25 $ m_ \ odot $ \ odot。对于二进制系统的情况，其祖细胞也可能是$ M_ \ Mathrm {Zams} \ Gtrsim 25 $ $ M_ \ odot $的星星。
SN 2018hti is a Type I superluminous supernova (SLSN~I) with an absolute $g$-band magnitude of $-22.2$ at maximum brightness, discovered in a metal-poor galaxy at a redshift of 0.0612. We present extensive photometric and spectroscopic observations of this supernova, covering the phases from $\sim -35$ days to more than +340 days from the $r$-band maximum. Combining our $BVgri$-band photometry with {\it Swift} UVOT optical/ultraviolet photometry, we calculated the peak luminosity as $\sim 3.5\times10^{44}$ erg s$^{-1}$. Modeling the observed light curve reveals that the luminosity evolution of SN 2018hti can be produced by an ejecta mass of 5.8 $M_\odot$ and a magnetar with a magnetic field of $B=1.8\times10^{13}$~G having an initial spin period of $P_0=1.8$ ms. Based on such a magnetar-powered scenario and a larger sample, a correlation between the spin of the magnetar and the kinetic energy of the ejecta can be inferred for most SLSNe~I, suggesting a self-consistent scenario. Like for other SLSNe~I, the host galaxy of SN 2018hti is found to be relatively faint ($M_{g} = -17.75$ mag) and of low metallicity ($Z=0.3~Z_\odot$), with a star-formation rate of 0.3 $M_\odot$ yr$^{-1}$. According to simulation results of single-star evolution, SN 2018hti could originate from a massive, metal-poor star with a zero-age main sequence (ZAMS) mass of 25--40 $M_\odot$, or from a less massive rotating star with $M_\mathrm{ZAMS} \approx 16$--25 $M_\odot$. For the case of a binary system, its progenitor could also be a star with $M_\mathrm{ZAMS} \gtrsim 25$ $M_\odot$.
