RT Journal Article
T1 Orbital angular momentum in the pion and kaon: Rest-frame and light-front
A1 Xiao, Yuyang
A1 Xu, Zhen-Ni
A1 Yao, Zhao-Quian
A1 Roberts, Craig D.
A1 Rodríguez Quintero, José
AB Orbital angular momentum (OAM) is not a Poincaré invariant quantity; so, its value is observer dependent. Notwithstanding that, in quantum chromodynamics, a Poincaré-invariant theory, OAM is part of every hadron wave function. Using continuum Schwinger function methods, we elucidate both the subjective character of in-hadron OAM and expose some of its impacts on pion and kaon structure and observables. For instance, working with light-front projections of their Bethe-Salpeter wave functions, it is found that the pion is a roughly 50/50 mix of light-front OAM zero and one components and the kaon is a 60/40 system. The overall picture is that (near) Nambu-Goldstone modes are complex bound states, each with significant intrinsic OAM, independent of the observer’s reference frame. This feature must be accounted for in the calculation of observables. Inductively, the same is true for all hadrons.
PB Elsevier
SN 0370-2693
SN 1873-2445 (electrónico)
YR 2026
FD 2026
LK https://hdl.handle.net/10272/28326
UL https://hdl.handle.net/10272/28326
LA eng
NO Xiao (肖宇洋), Y.-Y., Xu (徐珍妮), Z.-N., Yao (姚照千), Z.-Q., Roberts, C. D., & Rodríguez-Quintero, J. (2026). Orbital angular momentum in the pion and kaon: Rest-frame and light-front. Physics Letters B, 876, 140361. https://doi.org/10.1016/j.physletb.2026.140361
NO Work supported by: National Natural Science Foundation of China, grant no. 12135007; Helmholtz-Zentrum Dresden-Rossendorf, under the High Potential Pro-gramme; and Ministerio Español de Ciencia, Innovación y Universidades (MICINN) grant no. PID2022-140440NB-C22.
DS Repositorio Institucional de la Universidad de Huelva
RD 14 jul 2026