Gravitational potentials modified by extra dimensions : an analysis of alpha decay in the context of the Brane-world model

Abstract

In this work, we present an introduction to large extra-dimensional theories, in which modifications to the gravitational interaction are predicted at microscopic scales. We then review Gamow’s theory of alpha decay and extend it to a scenario involving extra dimensions, with the aim of investigating the influence of a modified gravitational potential on the decay rate of heavy radioactive nuclei. In the short-distance regime, compared with the size of the extra dimensions, the modification of the gravitational potential is described by a power-law behavior. In the long-distance regime, on the other hand, Yukawa- type corrections are employed to characterize the asymptotic behavior of the modified gravitational potential. Based on this theoretical framework, and using experimental alpha-decay data from 158 isotopes, we were able to establish independent experimental constraints on the parameters of extra-dimensional models by means of a least-squares fitting technique. In our analysis, scenarios with different numbers of extra dimensions were considered, and constraints were imposed on the main model parameters, including the effective nuclear radius, the higher-dimensional Planck length, and the parameters associated with the Yukawa parametrization.