Mass and decay angles in the Ξc--Ξc' mixing tension: Virtual hybrids and a single-direction criterion
Abstract
We compare three definitions of Ξc--Ξc' mixing within a constituent-quark model: a spin-component probability angle, a common-source overlap angle, and an SU(3)-breaking mass-operator angle. The probability angle is 3.11∘, while the two operator-based definitions give $2.48−−2.58^\circ$; a second parameter set gives $2.38−−2.49^\circ$. The operator-based angles are closer to the lattice determinations 1.2(1)∘ and 0.810(50)(200)∘, but remain larger. We then couple conventional qsQ states to virtual qsQg configurations, where q=u,d and Q=c,b. An orbital-S-wave chromomagnetic transition containing both jQg=1/2 and 3/2 raises the source and mass-operator charm angles to $2.67−−3.16^\circ$ when normalized to reference short-range mass shifts. The hybrid probability stays below 1.7%, and the corresponding bottom angles are $0.42−−0.48^\circ$. Eliminating the hybrid sector gives a rank-one mass correction precisely when all weighted transitions select the same retained-state combination. The mode-resolved calculation separates the flavor-breaking response that changes the mixing angle from the response that generates a second transition direction. The accompanying effective-current relation connects this mass analysis to radiative and semileptonic amplitudes through their current matrix elements.
Related
- Twisted Kagome Bilayers: High-Order Van Hove Singularities, Sublattice Interference, Magic Angles, and Possible Topology
- Neutrino masses and mixing angles in the Plan B Model
- Colloidal Suspensions can have Non-Zero Angles of Repose below the Minimal Value for Athermal Frictionless Particles
- Projection Angles of Projectiles in Sports: Qualitative Assessment of the Effects of Aerodynamic Forces or Run-Up
- Migrating cell clusters as active droplets with asymmetric shape and contact angles
BibTeX
@misc{kim2026mass,
title = {{Mass and decay angles in the $Ξ_c$--$Ξ_c'$ mixing tension: Virtual hybrids and a single-direction criterion}},
author = {Sanghoon Kim and Gihwan Nam and Jongheon Baek},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.12525},
eprint = {2610.12525},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.12525},
}
RIS
TY - UNPB
TI - Mass and decay angles in the Ξ_c--Ξ_c' mixing tension: Virtual hybrids and a single-direction criterion
AU - Sanghoon Kim
AU - Gihwan Nam
AU - Jongheon Baek
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.12525
UR - https://arxiv.org/abs/2610.12525
AB - We compare three definitions of Ξ_c--Ξ_c' mixing within a constituent-quark model: a spin-component probability angle, a common-source overlap angle, and an SU(3)-breaking mass-operator angle. The probability angle is 3.11^∘, while the two operator-based definitions give $2.48−−2.58^\circ$; a second parameter set gives $2.38−−2.49^\circ$. The operator-based angles are closer to the lattice determinations 1.2(1)^∘ and 0.810(50)(200)^∘, but remain larger. We then couple conventional qsQ states to virtual qsQg configurations, where q=u,d and Q=c,b. An orbital-S-wave chromomagnetic transition containing both j_Qg=1/2 and 3/2 raises the source and mass-operator charm angles to $2.67−−3.16^\circ$ when normalized to reference short-range mass shifts. The hybrid probability stays below 1.7%, and the corresponding bottom angles are $0.42−−0.48^\circ$. Eliminating the hybrid sector gives a rank-one mass correction precisely when all weighted transitions select the same retained-state combination. The mode-resolved calculation separates the flavor-breaking response that changes the mixing angle from the response that generates a second transition direction. The accompanying effective-current relation connects this mass analysis to radiative and semileptonic amplitudes through their current matrix elements.
ER -