Chromoelectric and chromomagnetic matching to scalar and spin-two nucleon structure
Abstract
Compact heavy quarkonium couples through the multipole interaction to scalar and spin-two gluonic operators. At leading chromoelectric order the corresponding matching coefficients satisfy ; an independent chromomagnetic polarizability lifts this relation within the general CP-even, spin-independent, local two-gluon interaction at dimension four and zero derivative order. We construct an RG-consistent realization in a fixed convention. The QCD trace identity converts the gluon-only scalar matching condition into an invariant basis and fixes the correlated quark-mass coefficient required when the interaction is re-expressed in the scale-dependent basis away from the matching scale, whereas leading-logarithmic singlet evolution induces a quark spin-two coefficient. In threshold-aligned symmetric kinematics, the canonical-spin non-flip projection contains and the combination . An explicit Breit-frame calculation relates this projection to an off-diagonal helicity representation for nonzero spacelike ; the off-diagonal form is kinematic rather than an additional dynamical spin flip. Linearity of the scalar and spin-two evolution factorizes the chromomagnetic dependence of their ratio as within the gluon-only dimension-four matching setup. The result separates state-dependent quarkonium matching from scalar and gravitational nucleon structure and states explicitly the assumptions under which this factorization holds.
Cite
@article{arxiv.2607.18831,
title = {Chromoelectric and chromomagnetic matching to scalar and spin-two nucleon structure},
author = {Arkadiy I. Syamtomov},
journal= {arXiv preprint arXiv:2607.18831},
year = {2026}
}
Comments
10 pages, 1 figure