Optical and UV Re-brightening of Hydrogen-rich Super-Luminous Supernova PS16dtm/SN 2016ezh
ATel #9843; Subo Dong, Ping Chen, S. Bose (KIAA-PKU), K. Z. Stanek, C. S. Kochanek, T. W.-S. Holoien (OSU), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), Peter J. Brown (Mitchell Institute/Texas A&M) & P. Milne (U. Arizona)
on 10 Dec 2016; 09:43 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Subo Dong (email@example.com)
Subjects: Optical, Ultra-Violet, Supernovae
PS16dtm/SN 2016ezh was discovered by Pan-STARRS1 on 2016-08-12 at ~ 17.1 mag, and it was classified by Asiago Transient Classification Program on 2016-08-27 as a Type II supernova (Atel #9417). Optical and UV monitoring from All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), 1m telescopes of Las Cumbres Observatory and Swift UVOT showed that it reached a peak around 2016-09-20 at V ~ 16, U ~ 14.8 and UVW1 ~ 15.3. At z = 0.08, it has absolute peak magnitude M_V ~ -21.7, belonging to the category of SLSN (Gal-Yam 2012). After this peak, this SLSN-II steadily declined in UV and optical, and it reached a minimum in flux at V~16.2 around 2016-10-20. Since then, it has re-brightened again in UV and optical, and it reached V ~ 16 and U ~ 14.8 at around 2016-11-10. It has since stayed at similar brightness for about a month. See this URL for preliminary photometry.
It is worth noting that ASASSN-15lh, classified by Dong et al. (2016) as SLSN-I, showed re-brightening in UV (see e.g., Brown et al., 2016; Godoy-Rivera et al., 2016).
We thank PI Neil Gehrels and the Swift ToO team for promptly approving and executing our observations. We thank LCOGT and its staff for their continued support of ASAS-SN. ASAS-SN is supported by NSF grant AST-1515927, the Center for Cosmology and AstroParticle Physics (CCAPP) at OSU, the Chinese Academy of Sciences South America Center for Astronomy (CASSACA), and the Mt. Cuba Astronomical Foundation. For more information about the ASAS-SN project, see the ASAS-SN Homepage and the list of all ASAS-SN transients.
Preliminary Light Curve for PS16dtm/SN 2016ezh