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arXiv · 1801.08241

First release of high-redshift superluminous supernovae from the Subaru HIgh-Z sUpernova CAmpaign (SHIZUCA). II. Spectroscopic properties

Chris Curtin·Jeff Cooke·Takashi J. Moriya·Masayuki Tanaka·Robert M. Quimby·Stephanie R. Bernard·Lluis Galbany·Ji-an Jiang·Chien-Hsiu Lee·Keiichi Maeda·Tomoki Morokuma·Ken'ichi Nomoto·Giuliano Pignata·Tyler Pritchard·Nao Suzuki·Ichiro Takahashi·Masaomi Tanaka·Nozomu Tominaga·Masaki Yamaguchi·Naoki Yasuda
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Abstract

We present Keck spectroscopic observations of three probable high redshift superluminous supernovae (SLSNe) from the Subaru HIgh-Z sUpernova CAmpaign (SHIZUCA), confirming redshifts of 1.851, 1.965 and 2.399. The host galaxies were selected for transient monitoring from multi-band photometric redshifts. The supernovae are detected during their rise, and the classically scheduled spectra are collected near maximum light. The restframe far-ultraviolet (FUV;$\sim$1000A-2500A) spectra include a significant host galaxy flux contribution and we compare our host galaxy subtracted spectra to UV-luminous SNe from the literature. While the signal-to-noise ratios of the spectra presented here are sufficient for redshift confirmation, supernova spectroscopic type confirmation remains inconclusive. The success of the first SHIZUCA Keck spectroscopic follow-up program demonstrates that campaigns such as SHIZUCA are capable of identifying high redshift SLSNe with sufficient accuracy, speed and depth for rapid, well-cadenced and informative follow-up.

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Chris Curtin, Jeff Cooke, Takashi J. Moriya, Masayuki Tanaka, Robert M. Quimby, Stephanie R. Bernard, Lluis Galbany, Ji-an Jiang, Chien-Hsiu Lee, Keiichi Maeda, Tomoki Morokuma, Ken'ichi Nomoto, Giuliano Pignata, Tyler Pritchard, Nao Suzuki, Ichiro Takahashi, Masaomi Tanaka, Nozomu Tominaga, Masaki Yamaguchi, Naoki Yasuda. 2018-01-24. First release of high-redshift superluminous supernovae from the Subaru HIgh-Z sUpernova CAmpaign (SHIZUCA). II. Spectroscopic properties. https://doi.org/10.3847/1538-4365/ab07c8

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