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This results in a delayed arrival of the leading edge of the pulse at the exit of the magnet as compared with the corresponding arrival of the trailing edge, which means a pulse compression. The magnetic field effectuates a phase space transformation, translating the energy dispersion into a time correlated spread of trajectory lengths. The compression is made possible by the time correlated electron energy degression caused by beam loading in the accelerator. The peak current rises by this charge conserving compression from originally 10 A to about 100 A at the exit of the magnet. This beam enters the magnet with a pulse width (fwhm) of typically 10 ns and leaves it with a pulse width (fwhm) of 0.6 ns. It consists of five sectors with zero gradient fields and is designed to accept a 50% electron energy spread in the beam of the accelerator. The new evaluation results in a slight decrease of the effective capture resonance integral and improves the prediction of integral thermal benchmarks by 70 pcm to 200 pcm.Ī special 360° deflection magnet has been installed at the exit of the 150 MeV Geel Electron Linear Accelerator (GELINA). A description is given of the statistical properties of the resonance parameters and of the recommended values of the average parameters. The neutron transmissions and the capture cross sections calculated with the resonance parameters are compared with the experimental data. The experimental database and the method of analysis are described in this report. Compared with previous evaluations, the energy range for this resonance analysis was extended from 10 to 20 keV, taking advantage of the high resolution of the most recent ORELA transmission measurements. The neutron resonance parameters of ²³⁸U were obtained from a SAMMY analysis of high-resolution neutron transmission measurements and high-resolution capture cross section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) in the years 1970-1990, and from more recent transmission and capture cross section measurements performed at the Geel Linear Accelerator (GELINA).