The super-luminous object ASASSN-15lh ( SN2015L ) is an extreme event with a total energy E _ { rad } \simeq 1.1 \times 10 ^ { 52 } erg in black body radiation on par with its kinetic energy E _ { k } in ejecta and a late time plateau in the UV , that defies a nuclear origin .
It likely presents a new explosion mechanism for hydrogen-deprived supernovae .
With no radio emission and no H-rich environment we propose to identify E _ { rad } with dissipation of a baryon-poor outflow in the optically thick remnant stellar envelope produced by a central engine .
By negligible time scales of light crossing and radiative cooling of the envelope , SN2015L ’ s light curve closely tracks the evolution of this engine .
We here model its light curve by the evolution of black hole spin , during angular momentum loss in Alvén waves to matter at the Inner Most Stable Circular Orbit ( ISCO ) .
The duration is determined by \sigma = M _ { T } / M of the torus mass M _ { T } around the black hole of mass M : \sigma \sim 10 ^ { -7 } and \sigma \sim 10 ^ { -2 } for SN2015L and , respectively , a long GRB .
The observed electromagnetic radiation herein represents a minor output of the rotational energy E _ { rot } of the black hole , while most is radiated unseen in gravitational radiation .
This model explains the high-mass slow-spin binary progenitor of GWB150914 , as the remnant of two CC-SNe in an intra-day binary of two massive stars .
This model rigorously predicts a change in magnitude \Delta m \simeq 1.15 in the light curve post-peak , in agreement with the light curve of SN2015L with no fine-tuning .