STUDY OF THE REFLECTIVITY OF A PYROLYTIC-GRAPHITE CRYSTAL IN A NEUTRON DIFFRACTOMETER GEOMETRY

The computer program TISTA, developed previously, has been used to stu dy the characteristics of pyrolytic graphite (PG) crystal plane (002) as a monochromator of a neutron diffractometer. The calculations have been carried out considering the geometry of the proposed neutron diff ractometer at a radial beam port at the TRIGA Mark II research reactor of AERE, Savar, Bangladesh. This program may be used for any other di ffractometer geometries. The results obtained will be useful in select ing PG(002) monochromators with optimum mosaic spread and thickness. T hey will also help to set up experiments with maximum flux density for desired resolutions. (C) 1998 Elsevier Science Ltd. All rights reserv ed.