The production of the 180mHf nuclei in the photoproton
reaction 181Ta(γ,p) was studied at end-point bremsstrahlung
energies Eγmax = 35-95 MeV. The experiment was performed at the
electron linear accelerator LUE-40 NSC KIPT with the use of the γ
activation and off-line γ-ray spectroscopy.
The experimental values of the bremsstrahlung flux-averaged cross-sections
⟨σ(Eγmax)⟩m for the
181Ta(γ,p)180mHf reaction were determined, and at
Eγmax>55 MeV obtained for the first time.
The measured values, also as the literature data, are significantly exceed
the theoretical flux-averaged cross-sections ⟨σ(Eγmax)⟩th. The ⟨σ(Eγmax)⟩th values were calculated using the cross-section
σ(E) computed with the TALYS1.95 code for six different level density
models.
A comparative analysis of the calculated total cross-sections for the
reactions 181Ta(γ,p)180Hf and
181Ta(γ,n)180Ta was performed. It was shown that the
photoproton (γ,p) to photoneutron (γ,n) strength ratio is
consistent with the estimates based on the isospin selection rules and the
value from the (e,e′p) experiment.Comment: 9 pages, 4 figures, 2 table