Laser ionization time-of-flight mass spectrometry has been used to probe neutral species produced by laser ablation of graphite at 266nm and 1064nm. Arrival time profiles of the neutral species were measured by changing delay times of postionization. C
3 was the major species. The yields of C and C
2 normalized to that of C
3 at 266nm (0.4-0.75J/cm
2) were 0.16-0.17 and 0.13-0.15, respectively. The yields of C and C
2 at 1064nm (0.7-1.0J/cm
2) were 0.03-0.05 and 0.02-0.03, respectively. Arrival velocity distributions with different most probable or center-of-mass velocities were observed depending on ablation laser wavelength and fluence. However, C, C
2, and C
3 showed similar arrival velocity distributions. We discuss the formation of C, C
2, and C
3 in terms of a direct ejection process from the graphite surface and a collisional process in the ablation plume.
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