Studying the Ultraviolet Spectrum of the First Spectroscopically Confirmed Supernova at redshift two
M. Smith, M. Sullivan, R. C. Nichol, L. Galbany, C. B. D'Andrea, C. Inserra, C. Lidman, A. Rest, M. Schirmer, A. V. Filippenko, W. Zheng, S. Bradley Cenko, C. R… 展开作者
M. Smith, M. Sullivan, R. C. Nichol, L. Galbany, C. B. D'Andrea, C. Inserra, C. Lidman, A. Rest, M. Schirmer, A. V. Filippenko, W. Zheng, S. Bradley Cenko, C. R. Angus, P. J. Brown, T. M. Davis, D. A. Finley, S. Gonzalez-Gaitan, C. P. Gutierrez, R. Kessler, S. Kuhlmann, J. Marriner, A. Moller, P. E. Nugent, S. Prajs, R. Thomas, R. Wolf, A. Zenteno, T. M. C. Abbott, F. B. Abdalla, S. Allam, J. Annis, K. Bechtol, A. Benoit-Levy, E. Bertin, D. Brooks, D. L. Burke, A. Carnero Rosell, M. Carrasco Kind, J. Carretero, F. J. Castander, M. Crocce, C. E. Cunha, L. N. da Costa, C. Davis, S. Desai, H. T. Diehl, P. Doel, T. F. Eifler, B. Flaugher, P. Fosalba, J. Frieman, J. Garcia-Bellido, E. Gaztanaga, D. W. Gerdes, D. A. Goldstein, D. Gruen, R. A. Gruendl, J. Gschwend, G. Gutierrez, K. Honscheid, D. J. James, M. W. G. Johnson, K. Kuehn, N. Kuropatkin, T. S. Li, M. Lima, M. A. G. Maia, J. L. Marshall, P. Martini, F. Menanteau, C. J. Miller, R. Miguel, R. L. C. Ogando, D. Petravick, A. A. Plazas, A. K. Romer, E. S. Rykoff, M. Sako, E. Sanchez, V. Scarpine, R. Schindler, M. Schubnell, I. Sevilla-Noarbe, R. C. Smith, M. Soares-Santos, F. Sobreira, E. Suchyta, M. E. C. Swanson, G. Tarle, A. R. Walker
We present observations of DES16C2nm, the first spectroscopically confirmed hydrogen-free superluminous supernova (SLSN-I) at redshift z~2. DES16C2nm was discovered by the Dark Energy Survey (DES) Supernova Program, with follow-up photometric data from the Hubble Space Telescope, Gemini, and the European Southern Observatory Very Large Telescope supplementing the DES data. Spectroscopic observations confirm DES16C2nm to be at z=1.998, and spectroscopically similar to Gaia16apd (a SLSN-I at z=0.102), with a peak absolute magnitude of U=-22.26$\pm$0.06. The high redshift of DES16C2nm provides a unique opportunity to study the ultraviolet (UV) properties of SLSNe-I. Combining DES16C2nm with ten similar events from the literature, we show that there exists a homogeneous class of SLSNe-I in the UV (~2500A), with peak luminosities in the (rest-frame) U band, and increasing absorption to shorter wavelengths. There is no evidence that the mean photometric and spectroscopic properties of SLSNe-I differ between low (z<1) and high redshift (z>1), but there is clear evidence of diversity in the spectrum at <2000A, possibly caused by the variations in temperature between events. No significant correlations are observed between spectral line velocities and photometric luminosity. Using these data, we estimate that SLSNe-I can be discovered to z=3.8 by DES. While SLSNe-I are typically identified from their blue observed colors at low redshift (z<1), we highlight that at z>2 these events appear optically red, peaking in the observer-frame z-band. Such characteristics are critical to identify these objects with future facilities such as the Large Synoptic Survey Telescope, Euclid, and the Wide-Field Infrared Survey Telescope, which should detect such SLSNe-I to z=3.5, 3.7, and 6.6, respectively.
Characterizing Supernova Host Galaxies with FrankenBlast: A Scalable Tool for Transient Host Galaxy Association, Photometry, and Stellar Population Modeling
Northwestern University（西北大学）；Purdue University（普渡大学）；University of California, Santa Cruz（加州大学圣克鲁兹分校）；University of Iceland（冰岛大学）；University of Copenhagen（哥本哈根大学）；Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU)（宇宙物理与数学卡弗里研究所）；The Pennsylvania State University（宾夕法尼亚州立大学）；Swinburne University of Technology（斯威本科技大学）；Curtin University（科廷大学）；Macquarie University（麦考瑞大学）；Kavli Institute for Cosmological Physics, The University of Chicago（芝加哥大学卡弗里宇宙物理学研究所）；University of Chicago（芝加哥大学）；University of Arizona（亚利桑那大学）；The George Washington University（乔治华盛顿大学）；University of California, Berkeley（加州大学伯克利分校）；Radboud University（拉德堡德大学）；Liverpool John Moores University（利物浦约翰摩尔斯大学）；University of Leicester（莱斯特大学）；Australian National University（澳大利亚国立大学）；Cardiff University（卡迪夫大学）；Massachusetts Institute of Technology（麻省理工学院）；University of Hawai‘i（夏威夷大学）；Weizmann Institute of Science（魏茨曼科学研究所）；University of Minnesota（明尼苏达大学）；Princeton University（普林斯顿大学）
Ultraviolet Spectroscopy and TARDIS Models of the Broad-lined Type-Ic Supernova 2014ad
很少有已发表的关于剥层超新星的紫外光谱，至今也没有关于宽线Ic型超新星（SN Ic-bl）的。这些天体具有极高的喷射速度，是唯一与伽马射线暴（GRB）直接相关的超新星类型。在这里，我们提出了两个时代的HST/STIS光谱的SN Ic-bl 2014 ad，第一个紫外光谱的这类。我们补充了26个新的基于地面的光谱时代，增加了丰富的光谱时间序列。紫外光谱没有表现出很强的功能，并与其他SN IC光谱中观察到的UV加宽版本是一致的。我们测量Fe II 5169埃的速度，并表明SN 2014 ad有更高的喷出物速度比大多数SNe Ic都有和没有观察到的伽玛暴。我们使用TARDIS构建SN 2014 ad UV+光谱的模型，TARDIS是一种一维Monte-Carlo辐射传输光谱合成代码。这些模型在光学的多个时期都很好地拟合了数据，但低估了紫外线的通量，这可能是由于简化了假设。我们发现，需要在高速度下的高密度来重现光谱，假设球对称，$\sim$ 3 M $_\odot$的材料在$v >$ 22，000 km s $^{-1}$。我们的星云线拟合表明在低速下有一个陡峭的密度剖面。总之，这些结果意味着更高的总喷出物质量比估计从以前的光变曲线分析和预期的理论。这可以通过在低速度下密度分布的平坦化和喷出物中心附近的额外发射来协调。
SN 2025ogs: A Spectroscopically-Normal Type Ia Supernova at z = 2 as a Benchmark for Redshift Evolution
Space Telescope Science Institute（太空望远镜科学研究所）；Johns Hopkins University（约翰斯·霍普金斯大学）；University of Arizona（亚利桑那大学）；Oklahoma State University（俄克拉荷马州立大学）；University of California, Santa Cruz（加利福尼亚大学圣克鲁兹分校）
SN 2025ogs在z=2.05的红移下表现出正常Ia型超新星特性，其光谱和光变曲线符合标准模型，为未来高红移Ia型超新星样本提供基准，验证了Ia型超新星标准化在高红移下的稳定性。
The local ultraviolet signature of Type Ia supernova environments from HST and MUSE
Institute of Space Sciences (ICE-CSIC)（空间科学研究所）；Institut d’Estudis Espacials de Catalunya (IEEC)（加泰罗尼亚太空研究学院）；Department of Physics and Astronomy and PITT PACC, University of Pittsburgh（匹兹堡大学物理与天文系及PITT PACC）；European Southern Observatory（欧洲南方天文台）；Departamento de Física Teórica, Universidad Autónoma de Madrid (UAM)（马德里自治大学理论物理系）；Centro de Investigación Avanzada en Física Fundamental (CIAFF-UAM)（基础物理高级研究中心）；Institute for Astronomy, University of Hawai‘i（夏威夷大学天文学研究所）；Las Campanas Observatory, Carnegie Observatories（拉斯坎帕纳斯天文台，卡内基观测站）
Extreme Stellar Death and Galaxy Feedback at z = 2: A Rest-frame Ultraviolet Characterization of the Strongly Lensed Superluminous Supernova 2025wny
INAF, Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文观测台）；University of California, Santa Cruz（加州大学圣克鲁兹分校）；The University of Melbourne（墨尔本大学）
