Telescope Performance And Image Simulations Of The Balloon-Borne Coded-Mask Protomirax Experiment

In this work we present the results of imaging simulations performed with the help of the GEANT4 package for the protoMIRAX hard X-ray balloon experiment. The instrumental background was simulated taking into account the various radiation components and their angular dependence, as well as a detailed mass model of the experiment. We modelled the meridian transits of the Crab Nebula and the Galactic Centre (GC) region during balloon flights in Brazil (similar to-23 degrees of latitude and similar to 40 km of altitude) and introduced the correspondent spectra as inputs to the imaging simulations. We present images of the Crab and of three sources in the GC region: 1E 1740.7-2942, GRS 1758-258 and GX 1+4. The results show that the protoMIRAX experiment is capable of making spectral and timing observations of bright hard X-ray sources as well as important imaging demonstrations that will contribute to the design of the MIRAX satellite mission.