Late-time X-rays to map the Zoo of Engine-driven Stellar Explosions

We propose an in-depth study of a nearby long gamma-ray burst (GRB, z <=0.4) with XMM. Our synergistic multi-wavelength effort (radio, optical, Swift/XRT and proposed XMM) is designed to extract the true energy of these explosions and to reveal the activity of their central engines. This effort allows us to: (i) investigate whether sub-energetic GRBs share the same explosion mechanisms and central engines as ordinary GRBs; (ii) investigate what essential physical property enables only a small fraction of supernovae to harbor a relativistic outflow; (iii) understand if jet-driven explosions are common in all SNe. These objectives are only possible by expanding the current small sample of well-observed local GRBs and by drawing comparisons with cosmological GRBs and common SNe.