SN 2018bsz: significant dust formation in a nearby superluminous supernova

Understand

We investigate the thermal emission and the extinction from dust associated with the nearby (z = 0.0267) superluminous supernova (SLSN) 2018bsz.

• Our dataset combines daily-cadence, simultaneous optical and near-infrared coverage up to ~100 days with late-time (+1.7 yr) mid-infrared observations.
• At 230 days after light-curve peak, the SN is not detected in the optical, but shows a surprisingly strong near-infrared excess, with r - J > 3 mag and r - Ks > 5 mag.
• The temporal evolution of the infrared light curve allows us to assess whether the mid-infrared emission originates from newly formed dust, either in the SN ejecta or in a post-shock circumstellar shell, or instead from an infrared echo produced by pre-existing circumstellar or interstellar dust heated by the SN radiation.