2026/02/11 by Ulaş Özdem
Physics and Astronomy · #Quantum Chromodynamics and Particle Interactions #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism
paper · pdf · doi:10.1093/ptep/ptag109
Abstract We investigate the static electromagnetic properties of three charm–strange molecular tetraquark candidates with quantum numbers JP=1+, namely the DK∗ , D∗ K, and D∗ K∗ systems. The analysis is carried out within the framework of quantum chromodynamics (QCD) light-cone sum rules, using interpolating currents constructed from color-singlet meson bilinears to reflect their molecular configurations. Both perturbative and nonperturbative photon contributions are included, and numerical predictions for the magnetic and electric quadrupole moments are obtained. The magnetic moments are found to lie in the range of 1–3 nuclear magnetons, with the largest value associated with the D*K configuration. The quadrupole moments are an order of magnitude smaller, of order 10-3 fm2, indicating only weak deviations from spherical charge distributions. A flavor decomposition shows that the magnetic response is dominated by the light quarks, whereas the charm-quark contribution is strongly suppressed, a feature naturally expected for loosely bound hadronic molecules. The present analysis extends QCD light-cone sum-rule studies of exotic hadrons by providing a systematic determination of the electromagnetic moments of the D(∗ )K(∗ ) molecular systems. These results provide quantitative benchmarks and identify several qualitative fingerprints—most notably the vanishing electromagnetic moments of the neutral DK*, the strong charm-quark suppression, and the smallness of the quadrupole deformations—that, taken together, distinguish the molecular scenario from compact diquark–antidiquark interpretations and may offer useful guidance for future experimental studies of charm–strange exotic states.