Measurement of Relative Intensity of the discrete $\gamma$ rays from the thermal neutron capture reaction $^{155,157}$ Gd $(n,\gamma)$ using ANNRI detector (JPARC)

We have measured the discrete $\gamma$ rays from thermal neutron capture on enriched gadolinium targets ($^{155}$Gd and $^{157}$Gd) using the ANNRI Germanium Spectrometer at JPARC. The photo-peak efficiencies were calibrated from 0.2 to 9 MeV using $\gamma$ rays from the standard radioactive sources ($^{60}$Co, $^{152}$Eu) and prompt $\gamma$ rays from $^{35}$Cl$(n,\gamma)$ reaction. We have calculated the relative intensities of discrete $\gamma$ rays from $^{157}$Gd$(n,\gamma)$ reaction. We found that our data are in fair agreement with the values published by NNDC (CapGam). We present the relative intensities of discrete $\gamma$ rays from $^{155}$Gd$(n,\gamma)$ reaction measured for the first time.