The formation of C-2 during thermal decomposition of fullerene C-60 was studied behind shock waves by time dependent absorption and emission measurements. The experiments were performed in the temperature range 2450 less than or equal to T less than or equal to 3450 K at pressures in the range 1.1 less than or equal to p less than or equal to 2.0 bar. C-2 concentration profiles were measured with a ring dye laser spectrometer at v = 21393.12 cm(-1). Simultaneously, the time behavior of spectrally resolved light emitted from the shock-heated aerosol was recorded by an intensified CCD camera. A simplified reaction mechanism with both C-2 formation and consumption reactions was proposed, and the experimental results were discussed in terms of kinetic parameters. A rate coefficient of the initial reaction C-60 + Ar --> C-2 + C-58 + Ar, k(1) = 2.7 x 10(17) exp(-495 kJ/mol/RT) cm(3) mol(-1) s(-1), was determined. Two different moderls for the further decomposition of fullerene fragments were discussed and compared with computer simulations.