Utilizing (p,d) and (p,t) Reactions to Obtain (n,f) Cross Sections in Uranium Nuclei Via the Surrogate-Ratio Method
نویسندگان
چکیده
Utilizing (p,d) and (p,t) reactions to obtain (n, f) cross sections in uranium nuclei via the surrogate-ratio method The surrogate ratio method has been tested for (p, d) and (p, t) reactions on uranium nuclei. 236 U and 238 U targets were bombarded with 28-MeV protons and the light ion recoils and fission fragments were detected using the Silicon Telescope Array for Reaction Studies detector array at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The (p,df) reaction channels on 236 U and 238 U targets were used as a surrogate to determine the σ [ 236 U(n,f)]/σ [ 234 U(n,f)] cross-section ratio. The (p,tf) reaction channels were also measured with the same targets as a surrogate for the σ [ 235 U(n,f)]/σ [(233 U(n,f)] ratio. For the (p,df) and (p,tf) surrogate measurements, there is good agreement with accepted (n,f) values over equivalent neutron energy ranges of E n = 0–7 MeV and E n = 0–5.5 MeV, respectively. An internal surrogate ratio method comparing the (p, d) and (p,t) reaction channels on a single target is also discussed. The σ [ 234 U(n,f)]/σ [ 233 U(n,f)] and σ [ 236 U(n,f)]/σ [ 235 U(n,f)] cross-section ratios are extracted using this method for the 236 U and 238 U targets, respectively. The resulting fission cross-section ratios show relatively good agreement with accepted values up to E n ∼ 5 MeV.
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