Measurement of 14.54 MeV neutron induced reaction cross sections of Cr and Mn with covariance analysis

Abstract

The 50Cr(n,2n)49Cr, 52Cr(n,2n)51Cr, 52Cr(n,p)52V, 55Mn(n,2n)54Mn, 55Mn(n,α)52V and 55Mn(n,γ)56Mn reaction cross sections at the neutron energy of 14.54 ± 0.24 MeV were measured by using activation method along with off-line γ-ray spectrometry. The 27Al(n,p)27Mg monitor reaction was used for the 52Cr(n,p)52V and 55Mn(n,α)52V reactions, whereas the 197Au(n,γ)198Au monitor reaction for the 55Mn(n,γ)56Mn reaction. The 27Al(n,α)24Na monitor reaction was used for other three reactions. The neutron beam was generated from the T(d,n)4He reaction using the Purnima neutron generator at BARC, Mumbai. The covariance analysis for the uncertainties of reaction cross sections was performed by considering the correlations between different attributes. The present results were compared with the literature data, evaluated data of ENDF, ROSFOND, CENDL, JENDL and JEFF libraries as well as with the theoretical values based on TALYS-1.9 calculation.

Measurement of 14.54 ± 0.24 MeV neutron activation reaction cross sections of 93Nb, natMo with covariance analysis

“…The resolution of the HPGe detector had a FWHM of 1.8 keV at the photo-peak of 1332.5 keV γ-ray of 60 Co. Due to low γ-ray activity, the irradiated samples were measured at a distance of 1 cm from the end cap of the detector. The details of neutron energy calculations using GEANT4 simulations are given in our previous publication [26,27].…”

“…The meaning of terms, micro-correlation and detail calculations are given in refs. [27,31,39,40]. The fractional uncertainties with correlations of different attributes in obtaining the 93 Nb(n,α) 90m Y, 93 Nb(n,2n) 92m Nb and 92 Mo(n,p) 92m Nb reaction cross sections are presented in Table 4.…”

Measurement of the (n, 2n) reaction cross-sections of iodine and cesium induced by D-T neutrons with covariance analysis*

“…2. The efficiency calibration curve was fitted to a polynomial function to obtain the most accurate values using the following expression [23][24][25]33]:…”

“…In addition, the uncertainty accompanying the activation cross-section is essential in determining a reasonable margin, which contributes to both safety and economy in nuclear applications [23,24]. If several data points of the activation cross-sections are involved in determining the quantity of interest, the correlation (covariance) among the data points must also be considered to avoid overestimating or underestimating the uncertainty in the quantity of interest [25].…”

Measurement of neutron induced reaction cross sections of palladium isotopes at the neutron energy of 14.54 ± 0.24 MeV with covariance analysis

“…The details of neutron energy calculations using GEANT4 are given in refs. [27][28][29][30]. A deuterium beam having energy of 180 ± 0.1 keV, with envelope diameter of 0.47 cm, measured using a beam profile monitor on TiT target is simulated in GEANT4.…”