Angular distribution of $\gamma$ rays from the p-wave resonance of ${}^{118}$Sn

Abstract

The neutron energy-dependent angular distribution of $\gamma$ rays from ${}^{117}\mathrm{Sn}(n,\gamma )$ reaction was measured with germanium detectors and a pulsed neutron beam. The angular distribution was clearly observed in $\gamma$-ray emissions with an energy of 9327 keV which corresponds to the transition from a neutron resonance of ${}^{117}\mathrm{Sn}+n$ to the ground state of ${}^{118}\mathrm{Sn}$. The angular distribution causes an angular-dependent asymmetric resonance shape. An asymmetry $A_{\mathrm{LH}}$ was defined as $(N_{\mathrm{L}}-N_{\mathrm{H}})/(N_{\mathrm{L}}+N_{\mathrm{H}})$, where $N_{\mathrm{L}}$ and $N_{\mathrm{H}}$ are integrated values for lower- and higher-energy regions of a neutron resonance, respectively. We found that the $A_{\mathrm{LH}}$ has the angular dependence of $(A\cos {\theta }_{\gamma }+B)$, where ${\theta }_{\gamma }$ is the $\gamma$-ray emission angle with respect to the incident neutron momentum, with $A=0.394\pm 0.073$ and $B=0.118\pm 0.029$ in the 1.33 eV p-wave resonance.

arXiv comment5 pages, 5 figures

References in corpus (4)

• Angular Distribution of $\gamma$-rays from Neutron-Induced Compound States of ${}^{140}$La
• Transverse asymmetry of $\gamma$ rays from neutron-induced compound states of ${}^{140}\mathrm{La}$
• Energy dependent angular distribution of individual $\gamma$-rays in the ${}^{139}$La($n$, $\gamma$)${}^{140}$La* reaction
• Characterization of Germanium Detectors for the Measurement of the Angular Distribution of Prompt gamma-rays at the ANNRI in the MLF of the J-PARC

Cited by in corpus (3)

• Measurement of the transverse asymmetry of $\gamma$-rays in the ${}^{117}$Sn(n,$\gamma$)${}^{118}$Sn reaction
• Angular distribution of $\gamma$-rays from a neutron-induced $p$-wave resonance of ${}^{132}$Xe
• Measurements of neutron total and capture cross sections of ${}^{139}$La and evaluation of resonance parameters