Effect of kinetics parameters on transients calculations in external source driven subcritical VR-1 reactor

Kinetics parameters are of high importance for reactor transient analyses. Similarly, they play an important role in many experimental reactor techniques, especially in techniques for determination of reactivity (such as Source Jerk, Rod Drop, or Source Multiplication method). However, the amount of experiments through which the accuracy of kinetics parameters can be checked is rather limited. This study presents experimental data of several external source driven subcritical reactor transients at various system subcriticalities, observed via neutron detectors located at various core positions. The transients were also analyzed by Monte Carlo simulations using MCNP code and a point kinetics approach for two different nuclear data libraries: ENDF/B-VII and JEFF 3.1.1. The observed differences related to delayed neutron parameters characterization in the two libraries were investigated.