We present the results of CO(1-0) observations of the host galaxy of a Type I superluminous supernova (SLSN-I), SN2017egm, one of the closest SLSNe-I at z = 0.03063, by using the Atacama Large Millimeter/submillimeter Array. The molecular gas mass of the host galaxy is $M_{\rm gas} = (4.8 \pm 0.3) \times 10^9$ $M_{\odot}$, placing it on the sequence of normal star-forming galaxies in an $M_{\rm gas}$-star-formation rate (SFR) plane. The molecular hydrogen column density at the location of SN2017egm is higher than that of the Type II SN PTF10bgl, which is also located in the same host galaxy, and those of other Type II and Ia SNe located in different galaxies, suggesting that SLSNe-I have a preference for a dense molecular gas environment. On the other hand, the column density at the location of SN2017egm is comparable to those of Type Ibc SNe. The surface densities of molecular gas and the SFR at the location of SN2017egm are consistent with those of spatially resolved local star-forming galaxies and follow the Schmidt-Kennicutt relation. These facts suggest that SLSNe-I can occur in environments with the same star-formation mechanism as in normal star-forming galaxies.
Obscured Star Formation in the Host Galaxies of Superluminous Supernovae
本文介绍了在$0.1 < z < 0.3$上用Karl G. Jansky甚大阵。观测到四个主星系,其中两个主星系具有很高的恒星形成速率(SFR $>$ 20 $M_{\odot}$ yr $^{-1}$),是SLSN主星系中恒星形成最强烈的主星系。我们比较了射电SFR和光学SFR,发现三个宿主星系的射电SFR超过了$>$ 2倍,这表明存在尘埃遮蔽的恒星形成,这是无法跟踪的光学研究。根据光学SFR,三个宿主星系中有两个位于星系主序星,根据射电SFR,它们位于主序星之上。这表明SLSN宿主中星暴星系的比例比以前的研究估计的要高。通过射电SFR与尘埃未校正光学SFR的比值计算消光系数,发现宿主星系的消光系数随金属丰度的增加而增加,这与本星系的消光系数关系一致。我们还将一个约束脉冲星驱动的SN模型,预测准稳态同步辐射无线电发射。
A Hubble Space Telescope Survey of the Host Galaxies of Superluminous Supernovae
我们目前的哈勃太空望远镜(HST)的WFC 3紫外和近红外(nIR)成像的21个超亮超新星(SLSNe)的主机星系,提供了一个敏感的探头的恒星形成和恒星质量的主机。通过与核塌缩超新星(CCSNe)和长时伽马射线暴(LGRB)的光度和形态特征比较,我们发现SLSN宿主星系在紫外和近红外波段都更暗、更致密,在某些情况下我们几乎不能恢复MV ~-14附近的绝对星等。此外,地面光学观测和档案的结果,我们产生的光谱能量分布(SED)适合这些主机,并表明SLSN主机具有较低的恒星质量和恒星形成率。这在缺乏氢的I型SLSN宿主星系中最为明显,尽管II型富氢SLSN宿主星系与CCSNe的主体星系仍然不同,跨越了非常宽的绝对星等范围,其中约30%的SLSNe-II来自比Mn I R ~-14更暗的星系。我们最微弱的SLSN主机的检测增加的信心,SLSNe-I主机是不同的LGRB的恒星形成率和恒星质量,并表明,金属丰度的明显相似性可能是由于有限的部分主机的发射线金属丰度测量是可行的。SLSN-II宿主的广泛光度范围很难通过金属丰度削减来描述,并且与任何合理的紫外加权光度函数的预期不匹配,这表明可能需要额外的环境限制来产生富含氢的SLSNe。
SN 2024afav: A Superluminous Supernova with Multiple Light Curve Bumps and Spectroscopic Signatures of Circumstellar Interaction
The NSF AI Institute for Artificial Intelligence and Fundamental Interactions(美国国家科学基金会人工智能与基本相互作用研究所);Department of Astronomy, University of Florida(佛罗里达大学天文系);Department of Astronomy, The University of Texas at Austin(德克萨斯大学奥斯汀分校天文系);Department of Physics, University of California, Santa Barbara(加州大学圣塔芭芭拉分校物理系);Steward Observatory, University of Arizona(亚利桑那大学斯图尔德天文台)
SN 2024afav是一颗具有多个光变曲线突起和光谱学特征的超亮I型超新星,其光谱学特征表明超新星喷射物与氢丰富的壳层之间存在相互作用。