The unprecedented center of mass energy available at the Large Hadron Collider (LHC) opens a new window for the exploration of Quark Gluon Plasma (QGP). Jet shape and jet topology measurements will become feasible as a new, differential, and accurate test of the underlying QCD theory and are instrumental in discovering novel effective interactions and phenomena that arise in matter under extreme conditions, allowing the development of precision radiography of strongly interacting plasmas. The project aims at studying the energy loss mechanisms in the Quark Gluon Plasma at the Large Hadron Collider (LHC) with the Compact Muon solenoid (CMS) detector: experimentally differentiate between radiative and collisional energy loss and address the problem of mass dependence of energy loss. The proposed tools for these studies are the heavy-quark tagged jets versus the accompanying light-parton jets, in the channel QQbar+jet. The tagging of these events will be accomplished by identifying, within a particular kinematic region, muon pairs produced in the simultaneous semi-leptonic decay of two heavy mesons. The techniques that will be used is the jet shape analysis. The shape of the energy and particle distribution of both the heavy-quark jet, and the accompanying light parton jet will be analyzed. The jet shape will be mapped both as a function of the cone radius and the transverse momentum distribution of particles inside the jet. This proposed exploratory research is the first of its kind in heavy-ion collisions and constitutes one of the first steps in developing the experimental bases of `jet tomography' of the QGP at the LHC. By taking a leading role, in a novel line of research (jet shape tomography of QGP) through this project, as member of an European institution, Laboratoire Leprince-Ringuet (LLR), the applicant will increase, quantitatively and qualitatively, the European potential for this research.