Deciphering the nature of $$ {P}_{\psi s}^{\Sigma} $$ pentaquarks in the light of their electromagnetic multipole moments

A bstract We calculate the electromagnetic multipole moments of the Σ-type strange hidden-charm pentaquarks $$ {P}_{\psi s}^{\Sigma} $$ P ψs Σ — which form an isospin triplet with three distinct charge states (Σ + , Σ 0 , Σ − ) offering independently measurable electromagnetic properties — using QCD light-cone sum rules, employing six interpolating currents for the spin- $$ \frac{1}{2} $$ 1 2 channel and seven for the spin- $$ \frac{3}{2} $$ 3 2 channel, each built from diquark-diquark-antiquark operators with scalar or axial-vector diquark content. We compute the magnetic dipole moment μ for all channels and, for spin- $$ \frac{3}{2} $$ 3 2 , the electric quadrupole $$ \mathcal{Q} $$ Q and magnetic octupole $$ \mathcal{O} $$ O moments, the latter two for the first time for this system, and provide the first systematic quark-flavor decomposition of all three multipole moments for $$ {P}_{\psi s}^{\Sigma} $$ P ψs Σ . The results show a systematic dependence on the diquark spin. Scalar diquark currents yield charm-sector-dominated, flavor-insensitive moments ( μ ∈ [−1.92, −1.21] μ N for spin- $$ \frac{1}{2} $$ 1 2 and | μ | ≲ 1.2 μ N for spin- $$ \frac{3}{2} $$ 3 2 ), consistent with the heavy-quark spin symmetry limit. Axial-vector diquark currents produce larger, flavor-sensitive moments with sign reversals governed by the e u / e d = –2 charge ratio. For $$ \mathcal{Q} $$ Q , scalar-diquark currents give oblate deformations ( Q 0 ≈ –2.0 × 10 −2 fm 2 ) dominated by the charm sector, while two-axial-vector-diquark currents predict prolate values up to Q 0 = +8.0 × 10 −2 fm 2 , with a sign reversal for $$ \left[ su\right]\left[ uc\right]\overline{c} $$ su uc c ¯ in two currents. Currents with scalar antiquark coupling yield a topology-independent octupole value $$ \mathcal{O} $$ O ≈ –0.25 × 10 −3 fm 3 , which may serve as a lattice QCD benchmark. Comparison with constituent quark model predictions identifies four qualitat