Photometric and spectroscopic evolution of the interacting transient AT 2016jbu(Gaia16cfr)

Brennan, S. J.; Fraser, M.; Johansson, J.; Pastorello, A.; Kotak, R.; Stevance, H. F.; Chen, T-W; Eldridge, J. J.; Bose, S.; Brown, P. J.; Callis, E.; Cartier, R.; Dennefeld, M.; Dong, Subo; Duffy, P.; Elias-Rosa, N.; Hosseinzadeh, G.; Hsiao, E.; Kuncarayakti, H.; Martin-Carrillo, A.; Monard, B.; Nyholm, A.; Pignata, G.; Sand, D.; Shappee, B. J.; Smartt, S. J.; Tucker, B. E.; Wyrzykowski, L.; Abbot, H.; Benetti, S.; Bento, J.; Blondin, S.; Chen, Ping; Delgado, A.; Galbany, L.; Gromadzki, M.; Gutierrez, C. P.; Hanlon, L.; Harrison, D. L.; Hiramatsu, D.; Hodgkin, S. T.; Holoien, T. W-S; Howell, D. A.; Inserra, C.; Kankare, E.; Kozlowski, S.; Muller-Bravo, T. E.; Maguire, K.; McCully, C.; Meintjes, P.; Morrell, N.; Nicholl, M.; O'Neill, D.; Pietrukowicz, P.; Poleski, R.; Prieto, J. L.; Rau, A.; Reichart, D. E.; Schweyer, T.; Shahbandeh, M.; Skowron, J.; Sollerman, J.; Soszynski, I; Stritzinger, M. D.; Szymanski, M.; Tartaglia, L.; Udalski, A.; Ulaczyk, K.; Young, D. R.; van Leeuwen, M.; van Soelen, B.
2022
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
DOI
10.1093/mnras/stac1243
We present the results from a high-cadence, multiwavelength observation campaign of AT 2016jbu (aka Gaia16cfr), an interacting transient. This data set complements the current literature by adding higher cadence as well as extended coverage of the light-curve evolution and late-time spectroscopic evolution. Photometric coverage reveals that AT 2016jbu underwent significant photometric variability followed by two luminous events, the latter of which reached an absolute magnitude of M-V similar to-18.5 mag. This is similar to the transient SN 2009ip whose nature is still debated. Spectra are dominated by narrow emission lines and show a blue continuum during the peak of the second event. AT 2016jbu shows signatures of a complex, non-homogeneous circumstellar material (CSM). We see slowly evolving asymmetric hydrogen line profiles, with velocities of 500 km s(-)(1) seen in narrow emission features from a slow-moving CSM, and up to 10 000 km s(-1) seen in broad absorption from some high-velocity material. Late-time spectra (similar to+1 yr) show a lack of forbidden emission lines expected from a core-collapse supernova and are dominated by strong emission from H, He I, and Ca II. Strong asymmetric emission features, a bumpy light curve, and continually evolving spectra suggest an inhibit nebular phase. We compare the evolution of H alpha among SN 2009ip-like transients and find possible evidence for orientation angle effects. The light-curve evolution of AT 2016jbu suggests similar, but not identical, circumstellar environments to other SN 2009ip-like transients.