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DOE OSTI Β· 2999059

Quadrupole forces between quark and gluon subsystems inside higher-spin particles

Kim, June-Young [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Inha University, Incheon (Korea, Republic of); Ecole Polytechnique, Palaiseau (France); Centre National de la Recherche Scientifique (CNRS) (France)] (ORCID:0000000256666819)Β·Kim, Hyun-Chul [Inha University, Incheon (Korea, Republic of); Korea Institute for Advanced Study (KIAS), Seoul (Korea, Republic of)] (ORCID:0000000287188661)
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Abstract

We generalize the mechanical interpretation of the forces between quark and gluon subsystems, previously studied for the nucleon, to arbitrary higher-spin particles. For spin-0 and spin-1/2 particles, this force is characterized by the nonconserved $\overline{𝑐}$⁑(𝑑) form factor. However, such an interpretation has not yet been established for higher-spin particles due to the intricate structure of the nonconserved energy-momentum tensor (EMT) form factors. By performing a multipole expansion, we identify the physically meaningful combinations of the nonconserved covariant EMT form factors and provide them with a clear mechanical interpretation.

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Kim, June-Young [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Inha University, Incheon (Korea, Republic of); Ecole Polytechnique, Palaiseau (France); Centre National de la Recherche Scientifique (CNRS) (France)] (ORCID:0000000256666819), Kim, Hyun-Chul [Inha University, Incheon (Korea, Republic of); Korea Institute for Advanced Study (KIAS), Seoul (Korea, Republic of)] (ORCID:0000000287188661). 2025-10-14. Quadrupole forces between quark and gluon subsystems inside higher-spin particles. https://doi.org/10.1103/r2t1-f4mc

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