Solution of the neutron spectrum adjustment problem in a typical MTR type research reactor

The work presented in this paper discusses the solution of the neutron energy spectrum adjustment problem in the Pakistan Research Reactor-1 (PARR-1), which is a typical Mate- rial Test Reactor (MTR) fuelled with low enriched uranium. This article examines how the di€erent adjustment codes such as SANDBP, MSANDB, MSITER and MIEKEB do mod- i®cation to the input spectrum and how this in turn a€ects the solution spectrum and the integral parameters. The e€ects of normalisation factor, weighting spectrum, group structure and treatment of inconsistencies on the solution spectrum have also been studied. The results obtained by the above adjustment codes have been compared and the criteria for selecting a solution spectrum from the many possible adjusted spectra have also been discussed