Explosion mechanisms and energy sources powering super-luminous supernovae

With bolometric peak luminosities L>7d43 erg/sec, the new class of Super Luminous Super Novae (SLSNe) outshine standard SN explosions of a factor ~10 and represent the death of the most massive stars in our Universe. Their exceptional luminosity requires exotic explosion mechanisms and/or sources of energy whose nature is unclear. Here we propose rapid Swift follow up of 2 SLSNe to map their UV and X-ray emission during the early stages of their evolution as part of our multi-wavelength effort through programs on the VLA, XMM, Chandra and optical/NIR facilities. The final aim is to: (i) Pin down the energy source of SLSNe; (ii) Map the diversity of their progenitor stars and pre-explosion evolution.