Measurement of 100Mo (n, 2n) 99Mo reaction cross section and covariance analysis using extended unscented transformation technique at the incident neutron energy of 13.9 MeV

Abstract

In this paper, the measurement and covariance analysis of the cross section of ¹⁰⁰Mo (n, 2n) ⁹⁹Mo reaction, with the ¹⁹⁷Au (n, 2n)¹⁹⁶Au reaction being used as the monitor, at the incident neutron energy of 13.9 MeV is reported. The ³H (d, n) ⁴He nuclear reaction is used as the neutron source. The experiment was performed at the Purnima neutron facility, BARC. The method of activation with off-line -ray spectrometry is used. The covariance analysis of the ¹⁰⁰Mo (n, 2n) ⁹⁹Mo reaction is also performed, for the first time, using the extended unscented transformation (EUT) technique¹, which is an extension of unscented transformation (UT) technique², for the determination of partial uncertainties arising due to attributes in combination with the micro-correlation technique of Geraldo and Smith³. The present results obtained for ¹⁰⁰Mo (n, 2n) ⁹⁹Mo reaction cross section are found to be in good agreement with EXFOR data and the theoretically calculated value using the TALYS 1. 8 code. Comparisons with the data in the available basic evaluated nuclear data libraries, such as ENDF/B-VIII.0, JEFF-3.3, JENDL-4.0, ROSFOND-2010, CENDL-3.1 and TENDL 2017 are also presented and discussed.