Slow blue nuclear hypervariables in PanSTARRS-1

Understand

We discuss 76 large amplitude transients (Delta-m>1.5) occurring in the nuclei of galaxies, nearly all with no previously known Active Galactic Nucleus (AGN).

• They have been discovered as part of the Pan-STARRS1 (PS1) 3pi survey, by comparison with SDSS photometry a decade earlier, and then monitored with the Liverpool Telescope, and studied spectroscopically with the William Herschel Telescope (WHT).
• Based on colours, light curve shape, and spectra, these transients fall into four groups.
• A few are misclassified stars or objects of unknown type.