INT WFC multi-band photometric follow up of the superluminous supernova SN 2018gft
ATel #12350; M. Mallorquin (ULL), E. M. Garcia-Zamora (ULL), A. Hernandez-Garcia (ULL & IAC), A. Alvarez-Hernandez (ULL), A. Alvarez-Saavedra (ULL), P. Carro-Portos (ULL), E. A. Diaz-Suarez (ULL), R. M. Doblas-Cabezas (ULL), M. Fernandez-Torreiro (ULL), J. E. Mendez-Delgado (ULL & IAC), D. Moral-Pombo (ULL), M. A. Nuñez-Cagigal (ULL & IAC), G. Panizo-Espinar (ULL), J. Sanchez-Sierras (ULL), D. SanJulian-Jacques (ULL), H. Villegas-Beberide (ULL), L. Monteagudo (ING), and I. Perez-Fournon (ULL & IAC)
on 2 Jan 2019; 14:21 UT
Credential Certification: Ismael Perez-Fournon (ipf@iac.es)
Subjects: Optical, Supernovae
We report multi-band photometry of the superluminous supernova SN 2018gft (= ZTF18abshezu) (= ATLAS18uym) based on CCD images taken with the Wide Field Camera of the Isaac Newton Telescope (Observatorio del Roque de los Muchachos, La Palma), from 2018 Oct 13.918 UT to 13.944 UT. According to the magnitudes we report below, SN 2018gft was about 1.7 magnitudes brighter during our observations than at the epoch of the first ZTF detection.
This supernova was discovered on 2018/09/02.335 by the ZTF survey and reported to TNS by C. Fremling et al. It was classified as SN Type SLSN-I at a redshift of z=0.23 by A. Dugas et al. (ATel #12051)
from spectroscopic follow-up with the Spectral Energy Distribution Machine (SEDM) mounted on the Palomar 60-inch (P60) telescope
(Blagorodnova et. al. 2018, PASP, 130, 5003). It was also detected by ATLAS (ATLAS18uym, TNS).
We report here the SN position, based on the INT images, calibrated using the Gaia DR2 catalog:
RA (J2000) = 23:57:17.933, Dec (J2000) = -15:37:53.37.
The INT Wide Field Camera magnitudes of SN 2018gft, calibrated using Pan-STARRS1 are:
g = 17.96 +/- 0.02 (2018 Oct 13.935), exposure time = 3 x 180 seconds
r = 18.10 +/- 0.02 (2018 Oct 13.932), exposure time = 3 x 180 seconds
i = 18.32 +/- 0.03 (2018 Oct 13.928), exposure time = 3 x 180 seconds
The host galaxy is not detected in the Pan-STARRS1 DR1 images (see
this comparison with our INT WFC r-band image) and the brightness of the SN does not allow us to detect a faint host galaxy at the position of the SN in the INT WFC images.
The light curve of SN 2018gft, from ZTF detections, represented in
Lasair #ZTF18abshezu
(see also MARS) shows, as expected for a SLSN-I, a very broad peak.
The INT WFC observations were carried out close to peak of the light curve in the interval without ZTF observations due to ZTF maintenance.
Based on observations made with the Isaac Newton Telescope operated on the island of La Palma by the Isaac Newton Group of Telescopes in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.
We thank David Bishop for his wonderful compilation of extragalactic novae and
supernovae.
SN 2018gft Isaac Newton Telescope Wide Field Camera r-band image