The operators of longitudinal and transverse ray transforms acting on vector fields on the unit disc are considered in the paper. The goal is to construct SVD-decompositions of the operators and invert them approximately by means of truncated decomposition for the parallel scheme of data acquisition. The orthogonal bases in the initial spaces and the image spaces are constructed using harmonic, Jacobi and Gegenbauer polynomials. Based on the obtained decompositions inversion formulas are derived and the polynomial approximations for the inverse operators are obtained. Numerical tests for data sets with different noise levels of smooth and discontinuous fields show the validity of the approach for the reconstruction of solenoidal or potential parts of vector fields from their ray transforms.

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A problem of reconstruction of 2D vector or symmetric 2-tensor fields by their known ray transforms is considered. Two numerical approaches based on the method of approximate inverse are suggested for solving the problem. The first method allows to recover components of a vector or tensor field, and the second reconstructs its potentials in the sense of feature reconstruction, where the observation operator assigns to a field its potential. Numerical simulations show good results of reconstruction of the sought-for fields or their solenoidal or potential parts from its ray transforms.

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