Testing the importance of collective correlations in neutrinoless ββ decay

We investigate the extent to which theories of collective motion can capture the physics that determines the nuclear matrix elements governing neutrinoless double-β decay. To that end we calculate the matrix elements for a series of isotopes in the full pf shell, omitting no spin-orbit partners. Wit...

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Detalles Bibliográficos
Autores: Menéndez, Javier, Ninohara, Nobuo, Engel, Jonathan, Martínez-Pinedo, Gabriel, Rodríguez, Tomás R.
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/679268
Acceso en línea:http://hdl.handle.net/10486/679268
https://dx.doi.org/10.1103/PhysRevC.93.014305
Access Level:acceso abierto
Palabra clave:Theories of collective
Neutrinoless
Double-β decay
Física
Descripción
Sumario:We investigate the extent to which theories of collective motion can capture the physics that determines the nuclear matrix elements governing neutrinoless double-β decay. To that end we calculate the matrix elements for a series of isotopes in the full pf shell, omitting no spin-orbit partners. With the inclusion of isoscalar pairing, a separable collective Hamiltonian that is derived from the shell model effective interaction reproduces the full shell-model matrix elements with good accuracy. A version of the generator coordinate method that includes the isoscalar pairing amplitude as a coordinate also reproduces the shell model results well, an encouraging result for theories of collective motion, which can include more single-particle orbitals than the shell model. We briefly examine heavier nuclei relevant for experimental double-β decay searches, in which shell-model calculations with all spin-orbit partners are not feasible; our estimates suggest that isoscalar pairing also plays a significant role in these nuclei, though one we are less able to quantify precisely.