Abstract
At low temperatures and medium excitation levels, a series of emission lines was discovered in silicon slightly doped with phosphorus or boron. Beginning with the bound exciton, the series converges towards the energetic position of the maximum of emission of the condensed electron-hole state. The sharpness of these lines and the characteristic dependence of their intensities on doping level and on excitation level suggest a model of multiple-exciton complexes bound to the impurities.