Cross Section Measurement for ¹⁹⁹Hg(n, n')^199mHg Reaction from 0.78 to 6.3 MeV

Abstract

Cross sections for the ¹⁹⁹Hg (n, n')^199mHg reaction have been measured at 10 energy points from 0.78 to 6.3 MeV by the activation method. Monoenergetic neutrons below 2 MeV were produced by the ⁷Li(p, n)⁷Be reaction and those above 2 MeV were produced by the D (d, n)³He reaction using a 5.5 MV Van de Graaff accelerator. The neutron flux was determined with a proton recoil telescope counter and In-foils. The measured cross sections were expressed by an empirical formula. The fission spectrum averaged cross section calculated with this formula is 238.3 mb for the Watt-type fission spectrum, and is about 14% smaller than that recently measured by three of the authors.