Popis: |
In the few-MeV energy range below the (p,n) threshold, gamma rays are produced from proton bombardment of aluminum via the 27 Al(p,p′γ) 27 Al, 27 Al(p,α,γ) 24 Mg, and 27 Al(p,γ) 28 Si reactions. Thick-target γ-ray yield data are important for various applications, including radiation shielding near accelerators and γ-ray background interference in experiments that focus on other materials. We measured p+Al γ-ray spectra over the photon energy range 0.5–15 MeV and at 0° and 90° laboratory angle relative to the incident proton beam. In the experiment, mono-energetic proton beams of 1.75, 2, 2.5, 3, 3.5, and 4 MeV irradiated thick stopping targets of pure aluminum. The resulting gamma rays were detected by 7.62×7.62 cm 2 NaI scintillation detectors. The spectra were unfolded using detector response functions calculated with the Monte Carlo code MCNP-4C. We report γ-ray spectra and tabulated γ-ray yields that can be used in applications that involve protons incident on thick aluminum targets at energies ⩽4 MeV. |