Double Beta Decay of 48Ca within EMPM and STDA methods

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F25%3A00645749" target="_blank" >RIV/61389005:_____/25:00645749 - isvavai.cz</a>

Result on the web

<a href="https://www.epj-conferences.org/articles/epjconf/abs/2025/27/epjconf_NuclearPhysics2025_01030/epjconf_NuclearPhysics2025_01030.html" target="_blank" >https://www.epj-conferences.org/articles/epjconf/abs/2025/27/epjconf_NuclearPhysics2025_01030/epjconf_NuclearPhysics2025_01030.html</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/epjconf/202534201030" target="_blank" >10.1051/epjconf/202534201030</a>

Result language

angličtina

Original language name

Double Beta Decay of 48Ca within EMPM and STDA methods

Original language description

The calculation of nuclear matrix elements (NMEs) for neutrinoless double-beta decay (0vßß) remains a major theoretical challenge in nuclear physics, as NMEs for this process cannot be accessed directly through experiment. Cur­rent nuclear structure models yield significantly different predictions for 0 vßß NMEs, making it essential to validate theoretical approaches using observables that are experimentally known. In contrast, two-neutrino double-beta decay (2vßß) has been measured in eleven isotopes, providing a valuable benchmark for testing the reliability of nuclear many-body methods.nnIn this work, we compute the 2vßß decay half-life of 48Ca using the Second Tamm-Dancoff Approximation (STDA) and the Equation of Motion Phonon Method (EMPM). By extending EMPM up to two-phonon configurations, we confirm that the two approaches yield practically identical numerical results, providing a strong internal consistency check. In addition, we study the de­pendence of the 2 vßß NME on the Gamow-Teller and Fermi contributions, on the particle-hole interaction strength parameter gph. Accurately reproducing the experimental 2 vßß half-life requires a substantial quenching of the axial-vector coupling constant gA. Furthermore, our theoretical framework outlines a strat­egy to mitigate this quenching issue by systematically including more complex configurations in the nuclear wave function.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

—

OECD FORD branch

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Project

<a href="/en/project/GA24-10180S" target="_blank" >GA24-10180S: Exploring the Properties of Neutrinos through Double Beta Decay: An Interplay between Theory and Experiment</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

EPJ Web of Conferences

ISBN

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ISSN

2100-014X

e-ISSN

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Number of pages

8

Pages from-to

01030

Publisher name

EDP sciences

Place of publication

Les Ulis

Event location

Ischia

Event date

May 19, 2025

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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