Experimental photoneutron cross sections of natural zirconium from 8 MeV to 134 MeV

The inclusive partial photoneutron cross sections and the total photoneutron cross section (sigma ^{(1)} (E_gamma ) = sumlimits_{i = 1}^{i_{max } } {sigma (gamma ,in...)} ) for natural Zr have been measured from 8 MeV to 134 MeV, with monochromatic photons obtained by in flight annihilation of monoenergetic positrons. The integrated total photoneutron cross section up tillE _γ=140 MeV is (1.59±0.11)σ ₀, whereσ ₀ is the Thomas-Reiche-Kuhn sum-rule. The integrated total photonuclear absorption cross section is evaluated to be (1.73±0.15)σ ₀. The behaviour of the total photoneutron cross section as a function of Eγ, in the 40 MeV <E _γ<140 MeV energy range, is well described by a modified version of the quasideuteron model.