AT 2018lqh and the Nature of the Emerging Population of Day-scale Duration Optical Transients

  title={AT 2018lqh and the Nature of the Emerging Population of Day-scale Duration Optical Transients},
  author={Eran O. Ofek and S. M. Adams and Eli Waxman and Amir Sharon and Doron Kushnir and Assaf Horesh and Anna Y. Q. Ho and Mansi M. Kasliwal and Ofer Yaron and A. Gal-Yam and Shrinivas R. Kulkarni and Eric C. Bellm and Frank J. Masci and David L. Shupe and Richard Dekany and M. Graham and Reed L. Riddle and Dmitry A. Duev and Igor Andreoni and Ashish A. Mahabal and Alyssa B. Drake},
  journal={The Astrophysical Journal},
We report on the discovery of AT 2018lqh (ZTF 18abfzgpl)—a rapidly evolving extragalactic transient in a star-forming host at 242 Mpc. The transient g-band light curve’s duration above a half-maximum light is about 2.1 days, where 0.4/1.7 days are spent on the rise/decay, respectively. The estimated bolometric light curve of this object peaked at about 7 × 1042erg s−1—roughly 7 times brighter than the neutron star (NS)–NS merger event AT 2017gfo. We show that this event can be explained by an… 


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