ULTRALUMINOUS SUPERNOVAE AS A NEW PROBE OF THE INTERSTELLAR MEDIUM IN DISTANT GALAXIES

作者：Berger E^*; Chornock R; Lunnan R; Foley R; Czekala I; Rest A; Leibler C; Soderberg A M; Roth K; Narayan G; Huber M E; Milisavljevic D; Sanders N E; Drout M; Margutti R; Kirshner R P; Marion G H; Challis P J; Riess A G; Smartt S J; Burgett W S; Hodapp K W; Heasley J N; Kaiser N; Kudritzki R P; Magnier E A; McCrum M; Price P A; Smith K; Tonry J L; Wainscoat R J

来源：Astrophysical Journal Letters, 2012, 755(2): L29.

DOI：10.1088/2041-8205/755/2/L29

• galaxies: ISM
• supernovae: individual (PS1-11bam)

We present the Pan-STARRS1 discovery and light curves, and follow-up MMT and Gemini spectroscopy of an ultraluminous supernova (ULSN; dubbed PS1-11bam) at a redshift of z = 1.566 with a peak brightness of M-UV approximate to -22.3 mag. PS1-11bam is one of the highest redshift spectroscopically confirmed SNe known to date. The spectrum exhibits broad absorption features typical of previous ULSNe (e.g., C II, Si III), and strong and narrow Mg II and Fe II absorption lines from the interstellar medium (ISM) of the host galaxy, confirmed by an [O II]lambda 3727 emission line at the same redshift. The equivalent widths of the Fe II lambda 2600 and Mg II lambda 2803 lines are in the top quartile of the quasar intervening absorption system distribution, but are weaker than those of gamma-ray burst intrinsic absorbers (i.e., GRB host galaxies). We also detect the host galaxy in pre-explosion Pan-STARRS1 data and find that its UV spectral energy distribution is best fit with a young stellar population age of tau(*) approximate to 15-45 Myr and a stellar mass of M-* approximate to (1.1-2.6) x 10(9) M-circle dot (for Z = 0.05-1 Z(circle dot)). The star formation rate inferred from the UV continuum and [O II]lambda 3727 emission line is approximate to 10 M-circle dot yr(-1), higher than in previous ULSN hosts. PS1-11bam provides the first direct demonstration that ULSNe can serve as probes of the ISM in distant galaxies. The depth and red sensitivity of PS1 are uniquely suited to finding such events at cosmologically interesting redshifts (z similar to 1-2); the future combination of LSST and 30 m class telescopes promises to extend this technique to z similar to 4.

• 出版日期2012-8-20