A New Class of Changing-look LINERs

  title={A New Class of Changing-look LINERs},
  author={Sara Frederick and Suvi Gezari and Matthew J. Graham and S. Bradley Cenko and Sjoert van Velzen and Daniel Stern and Nadejda Blagorodnova and Shrinivas R. Kulkarni and Lin Yan and Kishalay De and U. Christoffer Fremling and Tiara Hung and Erin Kara and David L. Shupe and Charlotte Ward and Eric C. Bellm and Richard Dekany and D. Duev and U. Feindt and Matteo Giomi and Thomas Kupfer and Russ R. Laher and Frank J. Masci and Adam A. Miller and Chow-Choong Ngeow and Maria T. Patterson and Michael E. Porter and Ben Rusholme and Jesper Sollerman and R. Walters},
  journal={The Astrophysical Journal},
We report the discovery of six active galactic nuclei (AGN) caught "turning on" during the first nine months of the Zwicky Transient Facility (ZTF) survey. The host galaxies were classified as LINERs by weak narrow forbidden line emission in their archival SDSS spectra, and detected by ZTF as nuclear transients. In five of the cases, we found via follow-up spectroscopy that they had transformed into broad-line AGN, reminiscent of the changing-look LINER iPTF 16bco. In one case, ZTF18aajupnt… 
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