The fluorescence spectrum of cesium vapor was studied in a cell irradiated with the light of 852.3 nm resonance line from a single mode laser diode. From the intensities and spectra of the Cs and Cs2 fluorescence we identified several collisional and radiative processes in the excited cesium atom-dimer system. The atomic lines of the highly excited states were the result of collisional energy transfer from Cs(6P 3/2) + Cs(6P 3/2) to Cs(6D, 8S) atoms. The Cs2 (B 1 IIu) band formed in Cs (6P) + Cs2 (X1sigmag+) collisions. The fine-structure mixing in 6 2P atoms was studied through excitation transfer, energy-pooling collision, and collisional excitation transfer between Cs2 and Cs. The authors estimated the value of rate coefficient for the collisional energy transfer from 6P3/2 to 6P1/2 to be (5.2+/-2.1) x 10(-11) cm3 x s(-1). For the excitation transfer process Cs2 (B 1 IIu)+ Cs(6S)--> Cs2 (X 1sigmag+) + Cs(6P1/2 ), a rate coefficient of (1.0+/-0.4) x 10(-9) cm3 x s(-1) was yielded.