  The Brazilian Multipurpose Reactor (RMB) is a fundamental project that aims
to turn Brazil into a self-sufficient country in the production of
radioisotopes and radiopharmaceuticals to supply the Unified Health System
(SUS) as much as the private institutions. In addition, the RMB project
describes other applications as irradiation and testing of nuclear fuels and
structural material analysis, for instance. There are many techniques in the
project to study structural aspects of materials, where neutron diffraction
represents one of the priorities for implementation. This technique will take
place mainly on two diffractometers on Thermal Neutron Guide 1 (TG1), namely
Araponga, a high-resolution diffractometer, and Flautim, a high-intensity
diffractometer. In this work, we study the performance of the Araponga
diffractometer through McStas simulations with input produced by the MCNP code
of the RMB core. We investigate the neutron flux values considering a
state-of-art high-resolution diffractometer, and the results are promising
since some simulated scenarios present values compatible with high-intensity
devices.
