@misc{10481/69269,
year = {2020},
month = {12},
url = {http://hdl.handle.net/10481/69269},
abstract = {We present and discuss the optical spectrophotometric observations of the nearby (z = 0.087) Type I superluminous supernova (SLSN I) SN 2017gci, whose peak K-corrected absolute magnitude reaches M-g = -21.5 mag. Its photometric and spectroscopic evolution includes features of both slow- and of fast-evolving SLSN I, thus favoring a continuum distribution between the two SLSN-I subclasses. In particular, similarly to other SLSNe I, the multiband light curves (LCs) of SN 2017gci show two re-brightenings at about 103 and 142 d after the maximum light. Interestingly, this broadly agrees with a broad emission feature emerging around 6520 angstrom after similar to 51 d from the maximum light, which is followed by a sharp knee in the LC. If we interpret this feature as H alpha, this could support the fact that the bumps are the signature of late interactions of the ejecta with a (hydrogen-rich) circumstellar material. Then we fitted magnetar- and CSM-interaction-powered synthetic LCs on to the bolometric one of SN 2017gci. In the magnetar case, the fit suggests a polar magnetic field B-p similar or equal to 6 x 10(14) G, an initial period of the magnetar P-initial similar or equal to 2.8 ms, an ejecta mass M-ejecta similar or equal to 9M(circle dot) and an ejecta opacity kappa similar or equal to 0.08 cm(2) g(-1). A CSM-interaction scenario would imply a CSM mass similar or equal to 5 M-circle dot and an ejecta mass similar or equal to 12M(circle dot). Finally, the nebular spectrum of phase + 187 d was modeled, deriving a mass of similar or equal to 10 M-circle dot for the ejecta. Our models suggest that either a magnetar or CSM interaction might be the power sources for SN 2017gci and that its progenitor was a massive (40 M-circle dot) star.},
organization = {PRIN-INAF 2017},
organization = {National Science Foundation (NSF)

AST1911225
AST-1813176
AST-2008108},
organization = {CONICYT PFCHA/DOCTORADOBECAS CHILE/2017 

72180113},
organization = {Polish NCN MAESTRO 

2014/14/A/ST9/00121},
organization = {Alexander von Humboldt Foundation},
organization = {European Commission

842471},
organization = {European Commission

839090},
organization = {European Commission

PGC2018-095317-B-C21},
organization = {VILLUM FONDEN 

19054},
organization = {Royal Astronomical Society Research Fellowship},
organization = {Marie Sklodowska-Curie Individual Fellowship within the Horizon 2020 European Union (EU) Framework Programme for Research and Innovation 

H2020-MSCA-IF-2017-794467},
organization = {National Science Foundation (NSF)

AST-1909796
AST-1238877},
organization = {University of Arizona 

2018A-UAO-G16},
organization = {Smithsonian Institution

2018A-UAO-G16},
organization = {National Aeronautics & Space Administration (NASA)

NW440
NNX08AR22G
NNX12AR65G
NNX14AM74G},
organization = {W.M. Keck Foundation},
organization = {Northwestern University},
organization = {Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)},
organization = {European Organisation for Astronomical Research in the Southern Hemisphere 

199.D-0143
0100.D-0751(B)
0101.D-0199(B)
099.A-9025(A)
0100.A-9099(A)099.A-9099
0100.A-9099},
organization = {German Research Foundation (DFG)},
organization = {European Commission

HA 1850/28-1},
organization = {National Aeronautics & Space Administration (NASA)

NNX12AR55G
80NSSC19k1639},
organization = {Google Summer of Code initiative},
organization = {ESA's Summer of Code in Space program},
organization = {European Commission

615929},
publisher = {Oxford University Press},
keywords = {Supernovae: general},
keywords = {Supernovae individual: SN 2017gci},
title = {SN 2017gci: a nearby Type I Superluminous Supernova with a bumpy tail},
doi = {10.1093/mnras/staa4035},
author = {Fiore, A. and Galbany González, Lluis},
}