Inclination of an object and possibilities for the construction of 3D tomograms based on two-dimensional projections

Abstract

An analysis of possibilities for reconstructing the spatial structure of a rotating object based on two-dimensional projections (images) as a function of the object inclination presented. For a 3D2D tomography, equal spatial resolutions for the summarized point spread function (SPSF) at the half-power beamwidth level along the rotation axis and in the orbital plane are obtained for an inclination i ~ 55°. This value is consistent with results for the 3D1D version, corresponding to the construction of 3D Doppler tomograms using one-dimensional projections. In contrast to the 3D1D case, increasing the inclination in the interval from55° to 90° leads to an only a slight difference in the two resolutions, and 90° is not a critical inclination. An appreciable reduction in the quality of model reconstructions is observed for inclinations below 20°. There is a complete loss of resolution along the rotation axis when the inclination is 0°. The radio-astronomical approach to the reconstructionmakes it possible to use a limited number of projections in the 3D2D case, and leads to smaller distortions than the filtered back-projectionmethod.