• Manish Sharma

Articles written in Pramana – Journal of Physics

• Measurement of neutron-induced activation cross-sections using spallation source at JINR and neutronic validation of the Dubna code

A beam of 1 GeV proton coming from Dubna Nuclotron colliding with a lead target surrounded by 6 cm paraffin produces spallation neutrons. A Th-foil was kept on lead target (neutron spallation source) in a direct stream of neutrons for activation and other samples of 197Au, 209Bi, 59Co, 115In and 181Ta were irradiated by moderated beam of neutrons passing through 6 cm paraffin moderator. The gamma spectra of irradiated samples were analyzed using gamma spectrometry and DEIMOS software to measure the neutron cross-section. For this purpose neutron fluence at the positions of samples is also estimated using PREPRO software. The results of cross-sections for reactions 232Th($n, \gamma$), 232Th($n, 2n$), 197Au($n, \gamma$), 197Au($n, \alpha$), 197Au($n, xn$), 59Co($n, \alpha$), 59Co($n, xn$), 181Ta($n, \gamma$) and 181Ta($n, xn$) are given in this paper. Neutronics validation of the Dubna Cascade Code is also done using cross-section data by other experiments.

• Role of $(n, xn)$ reactions in ADS, IAEA-benchmark and the Dubna Cascade Code

Dubna Cascade Code (version-2004) has been used for the Monte Carlo simulation of the 1500 MW$_{t}$ accelerator driven sub-critical system (ADS) with 233U + 232Th fuel using the IAEA benchmark. Neutron spectrum, cross-section of $(n, xn)$ reactions, isotopic yield, heat spectra etc. are simulated. Many of these results that help in understanding the IAEA benchmark are presented. It is revealed that the code predicts the proton beam current required for the 1500 MW$_{t}$ ADS for $K_{\text{eff}} = 0.98$ to be 11.6 mA. Radial distribution of heat is fairly in agreement with other codes like the EA-MC and it needs nearly 1% less enrichment than given by other codes. This may be because the code takes care of the role of larger order of the $(n, xn)$ reactions. It is emphasized that there is a strong need to study $(n, xn)$ reactions both theoretically and experimentally for better design.

• # Pramana – Journal of Physics

Volume 95, 2021
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019