Nuclear medium effects on the sigma mass and width

The meson meson interaction in the scalar isoscalar channel at finite baryonic density is studied in the framework of a chiral unitary approach which generates the f0 and sigma resonances and reproduces well the meson meson phase shifts in vacuum. We investigate the sigma spectral function, its mass and its width as a function of the baryon density and discuss possible experimental signatures in the (pi,2pi) and the (gamma,2pi) reactions.