Momentum-Current Gravitational Multipoles of Hadrons

We study multipole expansion of the momentum currents in hadrons with three series SoJ thorn , T & SIM;oJ thorn , and ToJ thorn in connection with the gravitational fields generated nearby. The momentum currents are related to their energy-momentum form factors, which in principle can be probed through processes like the deeply virtual Compton scattering currently studied at the Jefferson Lab 12 GeV facility and future Electron-Ion Collider. We define the leading momentum-current multipoles [the tensor monopole tau (T0) and scalar quadrupole sigma ij (S2) moments], relating the former to the so-called D term in the literature. We calculate the momentum-current distribution in the hydrogen atom and its monopole moment in the basic unit of tau 0 1/4 PLANCK CONSTANT OVER TWO PI2/4me, showing that the sign of the D term has little to do with mechanical stability. The momentum-current distribution also strongly modifies the static gravitational field inside hadrons.

Automated summary

This study investigates the multipole expansion of momentum currents in hadrons and their connection to nearby gravitational fields. The results show that the momentum-current distribution is not only related to energy-momentum form factors, but also strongly affects the static gravitational field inside hadrons.