Energy source and pre-explosion progenitor evolution of SuperLuminous Supernovae

With bolometric luminosities reaching L~10^45 erg/sec, the new class of Super Luminous Supernovae (SLSNe) outshine ordinary SNe a factor 100 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 a continuation of our successful XMM program to map their X-ray emission down to unprecedented limits as part of our multi-wavelength effort through our programs on the VLA (radio), Swift (UV) and optical/NIR facilities. The final aim is to: (i) Pin down the energy source of SLSNe; (ii) Map the diversity of the pre-explosion evolution of their progenitors.