D-term and structure of point-like and composed spin-0 particles

Abstract

This work deals with form factors of the energy-momentum tensor (EMT) of spin-0 particles and the unknown particle property D-term related to the EMT, and is divided into three parts. The first part explores free, weakly and strongly interacting theories to study EMT form factors with the following findings. (i) The free Klein-Gordon theory predicts for the D-term D = -1. (ii) Even infinitesimally small interactions can drastically impact D. (iii) In strongly interacting theories one can encounter large negative D though notable exceptions exist, which includes Goldstone bosons of chiral symmetry breaking. (iv) Contrary to common belief one cannot arbitrarily add "total derivatives" to the EMT. Rather the EMT must be defined in an unambiguous way. The second part deals with the interpretation of EMT form factors in terms of 3D-densities with following results. (i) The 3D-density formalism is internally consistent. (ii) The description is subject to relativistic corrections which are acceptably small in phenomenologically relevant situations including nucleon and nuclei. (iii) The free field result D=-1 persists when a spin-0 boson is not point-like but "heuristically given some internal structure." The third part investigates the question, whether such "giving of an extended structure" can be implemented dynamically, and has the following insights. (i) We construct a consistent microscopic theory which, in a certain parametric limit, interpolates between extended and point-like solutions. (ii) This theory is exactly solvable which is rare in 3+1 dimensions, admits non-topological solitons of Q-ball-type, and has a Gaussian field amplitude. (iii) The interaction of this theory belongs to a class of logarithmic potentials which were discussed in literature, albeit in different contexts including beyond standard model phenomenology, cosmology, and Higgs physics.

26 pages, 3 figures

References in corpus (19)

• Nucleon form-factors of the energy momentum tensor in the chiral quark-soliton model
• Towards a fitting procedure for deeply virtual Compton scattering at next-to-leading order and beyond
• The nucleon form-factors of the energy momentum tensor in the Skyrme model
• On LHCb pentaquarks as a baryon-psi(2S) bound state -- prediction of isospin 3/2 pentaquarks with hidden charm
• Dispersive evaluation of the D-term form factor in deeply virtual Compton scattering
• Gravitational and higher-order form factors of the pion in chiral quark models
• The pion mass dependence of the nucleon form-factors of the energy momentum tensor in the chiral quark-soliton model
• Radial excitations of Q-balls, and their D-term
• On the D-term of the nucleon generalized parton distributions
• Singular Charge Density at the Center of the Pion?
• Leading Chiral Corrections to the Nucleon Generalized Parton Distributions
• Energy momentum tensor, stability, and the D-term of Q-balls
• First Exclusive Measurement of Deeply Virtual Compton Scattering off ${}^4$He: Toward the 3D Tomography of Nuclei
• On the A-dependence of nuclear generalized parton distributions
• Pion transverse charge density from timelike form factor data
• Analyticity and sum rules for photon GPDs
• Dual parametrization of generalized parton distributions in two equivalent representations
• Stability of the pion and the pattern of chiral symmetry breaking
• Pion transverse charge density and the edge of hadrons

Cited by in corpus (4)

• Energy momentum tensor and the D-term in the bag model
• The energy-momentum tensor of spin-1 hadrons: formalism
• Effects of long-range forces on the D-term and the energy-momentum structure
• Monopole and quadrupole contributions to the angular momentum density