Signatures of Tev Scale Gravity in High Energy Collisions

International audienceIn TeV scale unification models, gravity propagates in 4+delta dimensions while gauge and matter fields are confined to a four-dimensional brane, with gravity becoming strong at the TeV scale. For a such scenario, we study strong gravitational interactions in an effective Schwarzschild geometry. Two distinct regimes appear. For large impact parameters, the ratio rho~(Rs/r0)1+delta, (with Rs the Schwarzschild radius and r0 the closest approach to the black hole), is small and the deflection angle chi is proportional to rho (this is like Rutherford-type scattering). For small impact parameters, the deflection angle chi develops a logarithmic singularity and becomes infinite for rho = rhoc = 2/(3+delta). This singularity is reflected into a strong enhancement of the backward scattering (like a glory-type effect). We suggest as distinctive signature of black hole formation in particle collisions at TeV energies, the observation of backward scattering events and their associated diffractive effects