SN 2017ens: The Metamorphosis of a Luminous Broadlined Type Ic Supernova into an SN IIn

We present observations of supernova (SN) 2017ens, discovered by the ATLAS survey and identified as a hot blue object through the GREAT program. The redshift z = 0.1086 implies a peak brightness of M = -21.1 mag, placing the object within the regime of superluminous supernovae. We observe a dramatic...

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Detalles Bibliográficos
Autores: Chen, T. W., Inserra, Cosimo, Fraser, Morgan, Moriya, T. J., Schady, P., Schweyer, T., Filippenko, Alexei V., Perley, D.A., Ruiter, A. J., Seitenzahl, I., Sollerman, J., Taddia, Francesco, Anderson, Joseph P., Foley, R. J., Jerkstrand, A., Ngeow, C. -C., Pan, Y. -C., Pastorello, Andrea, Points, S., Smartt, S. J., Smith, Ken W., Taubenberger, S., Wiseman, Philip, Young, D. R., Benetti, S., Berton, M., Bufano, F., Clark, P., Della Valle, M., Galbany, Lluís, Gal-Yam, Avishay, Gromadzki, M., Gutiérrez, Claudia P., Heinze, A., Kankare, E., Kilpatrick, C. D., Kuncarayakti, Hanindyo, Leloudas, Giorgos, Lin, Zhong-Yi, Maguire, Kate, Mazzali, Paolo A., McBrien, O., Prentice, S.J., Rau, A., Rest, Armin, Siebert, M. R., Stalder, B., Tonry, J. L., Yu, P. -C.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/216265
Acceso en línea:http://hdl.handle.net/10261/216265
Access Level:acceso abierto
Palabra clave:Supernovae: general
Supernovae: individual (SN 2017ens)
Descripción
Sumario:We present observations of supernova (SN) 2017ens, discovered by the ATLAS survey and identified as a hot blue object through the GREAT program. The redshift z = 0.1086 implies a peak brightness of M = -21.1 mag, placing the object within the regime of superluminous supernovae. We observe a dramatic spectral evolution, from initially being blue and featureless, to later developing features similar to those of the broadlined Type Ic SN 1998bw, and finally showing ∼2000 km s wide Hα and Hβ emission. Relatively narrow Balmer emission (reminiscent of a SN IIn) is present at all times. We also detect coronal lines, indicative of a dense circumstellar medium. We constrain the progenitor wind velocity to ∼50-60 km s based on P-Cygni profiles, which is far slower than those present in Wolf-Rayet stars. This may suggest that the progenitor passed through a luminous blue variable phase, or that the wind is instead from a binary companion red supergiant star. At late times we see the ∼2000 km s wide Hα emission persisting at high luminosity (∼3 × 10 erg s) for at least 100 day, perhaps indicative of additional mass loss at high velocities that could have been ejected by a pulsational pair instability. © 2018. The American Astronomical Society. All rights reserved.