RELATIVISTIC THEORY OF SPECTRAL CHARACTERISTICS OF PIONIC ATOMIC SYSTEMS: APPLICATION TO HEAVY SYSTEMS

A new theoretical approach to energy and spectral parameters of the hadronic (pionic and kaonic) atoms in the excited states with precise accounting for the relativistic, radiation and nuclear effects is presented. There are presented data of calculation of the energy and spectral parameters for pionic atoms of the 93Nb, 173Yb, 181Ta , 197Au, with accounting for the radiation (vacuum polarization), nuclear (finite size of a nucleus ) and the strong pion-nuclear interaction corrections. The measured values of the Berkley, CERN and Virginia laboratories and alternative data based on other versions of the Klein-Gordon-Fock theories with taking into account for a finite size of the nucleus in the model uniformly charged sphere and the standard Uhling-Serber potential approach for account for the radiation corrections are listed too.

Relativistic charged sphere in f(G,T) gravity

This study explores the interior geometry of static relativistic charged spheres in the background of a recently proposed modified [Formula: see text] gravity, where [Formula: see text] and [Formula: see text] are the Gauss–Bonnet (GB) invariant and trace of energy–momentum tensor, respectively. The GB gravity is the low-energy limit of superstring theories. The structures of specific relativistic charged spheres Vela [Formula: see text], [Formula: see text], and [Formula: see text] are studied in this theory of gravity. We analyzed several physical behaviors of these relativistic charged spheres with the help of observational data and investigated the various aspects like density profile, stresses, the distribution of charges, stability, etc.