Mathematical properties of generalized Sturmian functions

We study some mathematical properties of generalized Sturmian functions which are solutions of a Schrödinger-like equation supplemented by two boundary conditions. These generalized functions, for any value of the energy, are defined in terms of the magnitude of the potential. One of the boundary co...

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Detalles Bibliográficos
Autores: Ambrosio, Marcelo José, del Punta, Jessica Adriana, Rodriguez, Karina Viviana, Gasaneo, Gustavo, Ancarani, L. U.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/66531
Acceso en línea:http://hdl.handle.net/11336/66531
Access Level:acceso abierto
Palabra clave:Sturmian Functions
Scattering Problem
Green Operator
Atomic Collisionsions
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study some mathematical properties of generalized Sturmian functions which are solutions of a Schrödinger-like equation supplemented by two boundary conditions. These generalized functions, for any value of the energy, are defined in terms of the magnitude of the potential. One of the boundary conditions is imposed at the origin of the coordinate, where regularity is required. The second point is at large distances. For negative energies, bound-like conditions are imposed. For positive or complex energies, incoming or outgoing boundary conditions are imposed to deal with scattering problems; in this case, since scattering conditions are complex, the Sturmian functions themselves are complex. Since all of the functions solve a SturmLiouville problem, they allow us to construct a Sturmian basis set which must be orthogonal and complete: this is the case even when they are complex. Here we study some properties of generalized Sturmian functions associated with the Hulthén potential, in particular, the spatial organization of their nodes, and demonstrate explicitly their orthogonality. We also show that the overlap matrix elements, which are generally required in scattering or bound state calculations, are well defined. Many of these mathematical properties are expressed in terms of uncommon multivariable hypergeometric functions. Finally, applications to the scattering of a particle by a Yukawa and by a Hulthén potential serve as illustrations of the efficiency of the complex HulthénSturmian basis.