Formation and emission spectra of C2 swan band during the reaction of laser ablating target of aluminum with CF4 beam

The emission spectra of C2 Swan band transition has been observed in the 430nm-600nm region by Qswitch laser ablating target of Al and reacting with CF4 beam.Five vibrational band sequences (Δv=2,1,0,-1 and -2) of d3Πga3Πu are identified and the largest vibrational number of the excited state d is 6.Using a local thermal equilibrium model, the vibrational temperature of d state is about 6340K. Emission spectra from AlF have not been found. Comparing with the results of laserablated Al+O2 system and similar experiment of Cu+CF4 system, while the timeofflight profile of Al(2P1/2-2S1/2,3944nm)and(0,0)band head of C2 are analyzed, we consider that the primary reason of the producing of excited state d3Πg is the electronic energy transformation between excited states Al(2S1/2) and C2.