Quantum mechanics

Valence (chemistry)

Mathematical physics

Materials science

Chromatography

Nuclear physics

Particle physics

Neutrino

Ab initio

Computer science

Double beta decay

Matrix (chemical analysis)

Physics

Renormalization group

Composite material

Chemistry

Programming language

BETA (programming language)

Physical Review Letters

We calculate basis-space converged neutrinoless $\ensuremath{\beta}\ensuremath{\beta}$-decay nuclear matrix elements for the lightest candidates: $^{48}\mathrm{Ca}$, $^{76}\mathrm{Ge}$, and $^{82}\mathrm{Se}$. Starting from initial two- and three-nucleon forces, we apply the ab initio in-medium similarity renormalization group to construct valence-space Hamiltonians and consistently transformed $\ensuremath{\beta}\ensuremath{\beta}$-decay operators. We find that the tensor component is non-negligible in $^{76}\mathrm{Ge}$ and $^{82}\mathrm{Se}$, and the resulting nuclear matrix elements are overall 25%--45% smaller than those obtained from the phenomenological shell model. While a final matrix element with uncertainties still requires substantial developments, this work nevertheless opens a path toward a true first-principles calculation of neutrinoless $\ensuremath{\beta}\ensuremath{\beta}$ decay in all nuclei relevant for ongoing large-scale searches.

<i>Ab Initio</i> Neutrinoless Double-Beta Decay Matrix Elements for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>Ca</mml:mi></mml:mrow><mml:mprescripts /><mml:none /><mml:mrow><mml:mn>48</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>Ge</mml:mi></mml:mrow><mml:mprescripts /><mml:none…

Ab Initio Neutrinoless Double-Beta Decay Matrix Elements for Ca48 , Ge