Measuring the yields of isotopes produced in interaction of 1 GeV protons with a cylindrical lead target

The work is aimed at obtaining experimental data for selection and correction of parameters, used in calculation of yields of isotopes produced in splitting and fission reactions with high energy protons, bombarding heavy element targets with dimensions close to the range. Cylindrical lead target with assemblies of target-insertions, located in it, was irradiated in the accelerator by 1 GeV proton beam at μA mean beam current during 3 h. Measurements were conducted using a γ spectrometer with Ge(Li)-detector. The detector resolution made up 1.5 and 2.1 keV for 122 and 1332 keV lines. Over 40 isotopes were identified in the target-insertion spectra. Data, characterizing 201Pb, 194Au and 192Hg yield distribution by the target radius and depth, are obtained. These data analysis shows, that radial distributions of these isotopes at the front side and at the depths of 60 and 120 mm are close enough by the character, and the number of isotopes reduces about 100 times from the cener to the cylinder surface. Reduction of both absolute yield values and decrease slope from the center to the edge occurs at the depths of 300 and 540 mm. Yields of isotopes with the same or lower by one atomic number (201Pb, 202mPb, 199Te) have an evident maximum at the depths of 60-120 mm with subsequent smooth decrease along the target depth. Nuclide distributions of yields for isotopes with Z<(ZPb-1) either have a weakly expressed maximum or practically do not have it at all