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[en] The cross section for the reaction "1"1"5In(γ, γ′)_1_1_5_mIn was measured for photon energies in the range of E_γ ≅ 4–46 MeV. The parameters of the peak in this cross section near the threshold for the reaction "1"1"5In(γ, n), (E_γ)_(_γ_,_n_)"t"h"r, were refined. It is shown that, in the cross section for the reaction "1"1"5In(γ, γ′)"1"1"5"mIn at Eγ ∼ 27 MeV, there is no second peak for which δ_I_I"i"n"t would exceed about 0.2δ_I"i"n"t for the peak at E_γ ∼ (E_γ)_(_γ_,_n_)"t"h"r. The possibility of employing this reaction both in studying photonuclear reaction physics and in monitoring bremsstrahlung photons in gamma-activation studies was examined
[en] Average neutron flux of an old Am-Be neutron source was measured by utilizing the activation of 115In with neutrons from the source and measurement of the induced radioactivity of 115In using γ-ray spectrometry. The average neutron activation cross section for the nuclear reaction 115In(nn')115In was calculated using, effective cross section for the reaction 115In(nγ)115m using tabulated standard reference nuclear reaction cross section data library (TNDL) combined with the neutron distribution spectrum of combined with the neutron distribution spectrum of 241Am-Be source. The average neutron flux was determined using the photo peak intensity of 336.2 keV characteristic γ-photons emitted by 116In. The average neutron flux of the facility was found to be 2.7 x 105 n.cm-2.sec-1. (author)
[en] A geometry independent method has been derived for calculating the ratio of the spectrum averaged cross-sections for the reactions 115In(γ, γ')115mIn and 113In(γ, γ')113mIn in the energy region of interest 300-500 keV. The technique is unique as it eliminates the need for a detailed detector efficiency formulation for varying source-detector geometries, thereby removing a source of systematic uncertainty. The validity of the technique is demonstrated experimentally by comparing the cross-section ratios for a geometrically diverse set of source-detector configurations. The average ratio value for seven independent measurements is 0.778±0.0033 with a reduced χ2 of 1.2, which is within 1.15% of the previously published value.
[en] The dense plasma focus (DPF) device-DPF-1000U which is operated at the Institute of Plasma Physics and Laser Microfusion is the largest that type plasma experiment in the world. The plasma that is formed in large plasma experiments is characterized by vast numbers of parameters. All of them need to be monitored. A neutron activation method occupies a high position among others plasma diagnostic methods. The above method is off-line, remote, and an integrated one. The plasma which has enough temperature to bring about nuclear fusion reactions is always a strong source of neutrons that leave the reactions area and take along energy and important information on plasma parameters and properties as well. Silver as activated material is used as an effective way of neutrons measurement, especially when they are emitted in the form of short pulses like as it happens from the plasma produced in Dense Plasma-Focus devices. Other elements such as beryllium and yttrium are newly introduced and currently tested at the Institute of Plasma Physics and Laser Microfusion to use them in suitable activation neutron detectors. Some specially designed massive indium samples have been recently adopted for angular neutrons distribution measurements (vertical and horizontal) and have been used in the recent plasma experiment conducted on the DPF-1000U device. This choice was substantiated by relatively long half-lives of the neutron induced isotopes and the threshold character of the 115In(n,n')115mIn nuclear reaction. (author)