Two years of optical and NIR observations of the superluminous supernova UID 30901 discovered by the UltraVISTA SN survey

We present deep optical and near-infrared photometry of UID 30901, a superluminous supernova (SLSN) discovered during the UltraVISTA survey. The observations were obtained with VIRCAM (YJHK(s)) mounted on the VISTA telescope, DECam (griz) on the Blanco telescope, and SUBARU Hyper Suprime-Cam (HSC; grizy). These multiband observations comprise +700 d making UID 30901 one of the best photometrically followed SLSNe to date. The host galaxy of UID 30901 is detected in a deep HST F814W image with an AB magnitude of 27.3 +/- 0.2. While no spectra exist for the SN or its host galaxy, we perform our analysis assuming z = 0.37, based on the photometric redshift of a possible host galaxy found at a projected distance of 7 kpc. Fitting a blackbody to the observations, the radius, temperature, and bolometric light curve are computed. We find a maximum bolometric luminosity of 5.4 +/- 0.34 x 10(43) erg s(-1). A flattening in the light curve beyond 600 d is observed and several possible causes are discussed. We find the observations to clearly favour an SI,SN type I, and plausible power sources such as the radioactive decay of Ni-56 and the spin-down of a magnetar are compared to the data. We find that the magnetar model yields a good fit to the observations with the following parameters: a magnetic field B = 1.4 +/- 0.3 x 10(14) G, spin period of P = 6.0 +/- 0.1 ms, and ejecta mass M-ej = 11.9(-6.4)(+4.8) M-circle dot.

Automated summary

In this study, we present the optical and near-infrared photometry of the superluminous supernova UID 30901. By analyzing the image of the host galaxy and assuming a photometric redshift, we fit a blackbody model and find that the magnetar model is consistent with the observations.