Bolometric light-curve modeling reveals extremely high ejecta masses in SLSNe-I

I present the bolometric light-curve modeling of 98 hydrogen-poor superluminous supernovae (SLSNe- I) using three power input scenarios of the Minim code: the magnetar model, and the constant-density and the steady-wind versions of circumstellar interaction scenario (CSM models). Quasi-bolometric fluxes were constructed from ZTF g- and r-band photometry, while ejecta velocities were estimated from spectroscopic measurements. The modeling indicates that 14 events favor the magnetar scenario, the light curves of 39 objects are better described by circumstellar interaction, and 45 events show consistent light curves with either mechanism. Magnetar fits yield spin periods and magnetic field strengths in agreement with previous studies, but imply substantially larger ejecta masses. The mean ejecta mass for magnetar-powered models is 34.25 M ☉ (in the range between 1.53 and 198.1 M ☉), while circumstellar interaction models produce even higher values, with mean masses of 116.82 M ☉ for the constant-density case and 105.99 M ☉ for the steady-wind case. These large ejecta masses arise in part from the assumption of an electron-scattering opacity of κ = 0.2 and from higher inferred ejecta velocities. Overall, the results suggest that SLSNe-I, regardless of whether they are powered by a central engine or circumstellar interaction, originate from the explosions of extremely massive progenitor stars.