Measurement of theTm169(n,3n)Tm167

Abstract

The cross section for the 169 Tm(n,3n) 167 Tm reaction has been measured from 17 to 22 MeV using quasi-monoenergetic neutrons produced by the 2 H(d,n) 3 He reaction. This energy range was studied to resolve the discrepancy between previous (n,3n) cross-section measurements. In addition, the absolute γ-ray branching ratios following the electron-capture decay of 167 Tm were measured. These results provide more reliable nuclear data for an important diagnostic that is used at the National Ignition Facility to estimate the yield of reaction-in-flight neutrons produced via the inertial-confinement-fusion plasma in deuterium-tritium capsules.

Consistent optical potential for incident and emitted low-energy α particles. II. α emission in fast-neutron-induced reactions on Zr isotopes

“…The recently improved cross sections for reactions induced by reaction-in-flight (RIF) neutrons with energies up to 30 MeV in warm deuterium-tritium plasma [1], have concerned also 94 Zr(n, α) 91 Sr reaction. A significant body of measured data becomes thus available for α-particle emission in fast-neutron induced reactions on Zr isotopes, to be eventually used for assessment of the so-called α-potential mystery for the account at once of both absorption and emission of low-energy α-particles [2][3][4].…”

“…The agreement with the data was considered good only in view of the lack of detailed tuning of calculations, while especially with reference to α-particle emission it was stated the need of detailed further investigations for the improved physics modeling. Therefore, in order to obtain reliable results of the (n, α) reaction analysis for Zr isotopes and the related α-particle OMP, first it has become necessary a check of the model predictions for the rest of the measured fast-neutron reaction data available for these isotopes [1,9,12].…”

“…III. The results obtained for the fast-neutron induced reactions on Zr stable isotopes are then compared with the measured data [1,9,12] in Sec. IV, while the case of the α-particle emission makes the object of Sec.…”

Measurement of the Bi209(n,4n)Bi206 and Gooden1, Champine2, Combs3 et al. 2017Phys. Rev. CSelf Cite

“…The neutron energy distribution for the neutrons of interest was calculated based on the width of the neutron beam as determined by the NTOF once the detector resolution is unfolded and also included the 3 H(d,n) 4 He neutron angular distribution over the foil geometries weighted by the cross-section [3]. This calculation produces a neutron energy distribution for each incident neutron energy similar to the one in Fig.…”

“…It is clear from [2] that the cross section of the reaction is a necessary component in determining the stopping powers and therefore, the relevant nuclear data must be measured to fully interpret the results. In support of the RIF measurements, the 169 Tm(n,3n) 167 Tm cross-section has been recently measured [3]. As an additional measurement of the RIF neutron spectrum, the 209 Bi(n,4n) 206 Bi reaction is now being employed, with a threshold of 22.5 MeV.…”