The Cairo Fourier Diffractometer Facility At The ETRR-1 Reactor

The work presents the Cairo Fourier diffractometer facility (CFDF). The CFDF is based on the reverse time-of-flight (RTOF) concept and was recently installed, as IAEA TC Project, at one of the ET-RR-1 reactor horizontal channels. The CFDF performance is assessed and its main parameters are given. The facility applies a Fourier chopper system and 6Li-glass scintillators (NE-912) arranged according to the time focusing geometry in order to detect neutrons scattered from the sample at an angle 29= 90 diameter. The detector system has been optimized for studying the internal stresses in materials along with neutron diffraction measurements. Its angular aperture was found, from precise calculations, by a special program, to be equal to S.1 x 102 steradians. The neutron guide system attached to the CFDF provides a thermal neutron flux-l.lxl06n/cm2/sec at the sample position. It has been found, from measurements with different powder samples, that such value of the thermal neutron flux is adequate for neutron diffraction measurements, at scattering angle 2θ= 90ο and d-spacing values between 0.7 A and 2.5 A, within 0.45% resolution