The existence of two groups of carbon clusters in laser vaporization was confirmed by the covariance analysis and laser fluence dependence study. One is the clusters produced when the higher laser fluence is used, which most likely causes an atomization of graphite directly or very rapid-and-intense fragmentation of large carbon particles. And the vaporized atoms or small clusters grow to larger clusters by the confinement and clustering in the buffer gas. These clusters showed smooth ion distribution both for the cations and anions in the size region up to about a hundred. The other is produced when the laser fluence is lowered, These clusters showed the characteristic ion distribution with magic sizes at C-60(+), C-70+( )cations, and C-10(-), C-12(-), C-16(-), C-18(-),... anions. The origin of the clusters was suggested as the large hot clusters which lead to the fragmentation into these smaller clusters observed. (C) 1997 American Institute of Physics.