The jet formation in laser-produced particle beams has been investigated as a function of the atomic mass of the target. The plasma was produced by an obliquely incident Q-switched pulse (τ = 5 ns and λ = 1.06 µm) of a Nd:YAG laser focused onto a relatively large area of about 5 × 10 −4 cm 2 at an energy density of 26 J cm −2 . Angular emission distributions of absolute particle numbers have been measured for 27 Al, 48 Ti, 59 Ni, 96 Mo, 108 Ag, 119 Sn and 181 Ta targets for identical laser-target conditions. It is found that the measured angular emission profile and the number of particles ablated depend systematically on the atomic mass M . If the angular behaviour is described as usual in terms of a two-component structure by the superposition of a smooth cosine-like background distribution and an additional steep emission structure which is approximated by a cos n function, it is found that the exponent n gradually increases on going from Al to Ta, closely following a M 1/2 fit. Since the degree of ionization of the expanding plasma is relatively low, the observed angular behaviour is essentially that of the neutral particles.