Scattering of on-axis Gaussian beam by an arbitrarily shaped chiral object

•Having a semi-analytical solution to Gaussian beam scattering by a chiral object.•Determining the T-matrix relating to the expansion coefficients.•Extending the GLMT to the case of an arbitrarily shaped chiral object.

Based on a combination of the extended boundary condition method (EBCM) and generalized Lorenz-Mie theory (GLMT), a semi-analytical solution to the scattering of an on-axis Gaussian beam by an arbitrarily shaped chiral object is constructed, by expanding the incident Gaussian beam, scattered fields as well as internal fields in terms of appropriate spherical vector wave functions (SVWFs). The unknown expansion coefficients are determined by using Schelkunoff׳s equivalence theorem and continuous boundary conditions. Numerical results of the normalized differential scattering cross-section are presented, and the scattering characteristics are discussed concisely.