TY - JOUR A1 - Flad, Heinz-Jürgen A1 - Flad-Harutyunyan, Gohar A1 - Schulze, Bert-Wolfgang T1 - Explicit Green operators for quantum mechanical Hamiltonians BT - II. edge-type singularities of the helium atom JF - Asian-European journal of mathematics : AEJM N2 - We extend our approach of asymptotic parametrix construction for Hamiltonian operators from conical to edge-type singularities which is applicable to coalescence points of two particles of the helium atom and related two electron systems including the hydrogen molecule. Up to second-order, we have calculated the symbols of an asymptotic parametrix of the nonrelativistic Hamiltonian of the helium atom within the Born-Oppenheimer approximation and provide explicit formulas for the corresponding Green operators which encode the asymptotic behavior of the eigenfunctions near an edge. KW - Singular analysis KW - Schrodinger equation KW - many-electron systems KW - asymptotic properties of eigenfunctions Y1 - 2020 U6 - https://doi.org/10.1142/S1793557120501223 SN - 1793-5571 SN - 1793-7183 VL - 13 IS - 7 PB - World Scientific CY - Singapore ER -