Investigating fast neutron interaction with chromium nuclei

A new technique based on a Frisch grided ionization chamber and digital signal processing unit is used for low-background measurements of a cross section of the (n, α) reaction proceeding on a solid target mounted on a cathode. Measurements of the (n, α) reaction cross section for the ⁵⁰Cr and ⁵²Cr isotopes are carry out. It is shown that the data for ⁵⁰Cr differ from the ENDFB-VII evaluation by a factor of 20. The excitation function reveals a structure missing from our assessment. The ⁵²Cr(n, α) reaction cross section is measured for neutrons with energies of less than 14 MeV for the first time.