Perturbative results of matrix elements of the axial current and their relation with the axial anomaly
In the Standard Model of particle physics, the axial current is not conserved, due both to fermion masses and to the axial anomaly. Using perturbative quantum chromodynamics, we calculate matrix elements of the local and non-local axial current for a gluon target, clarifying their connection with the axial anomaly. In so doing, we also reconsider classic results obtained in the context of the nucleon spin sum rule as well as recent results for off-forward kinematics. An important role is played by the infrared regulator, for which we put a special emphasis on the nonzero quark mass. We highlight cancellations that take place between contributions from the axial anomaly and the quark mass, and we elaborate on the relation of those cancellations with the conservation of angular momentum.
Authors
- Adam Freese (ORCID: https://orcid.org/0000-0002-0688-4121)
- Andreas Metz (ORCID: https://orcid.org/0000-0002-0223-5618)
- Simone Rodini (ORCID: https://orcid.org/0000-0002-8057-5597)
- B. Pasquini (ORCID: https://orcid.org/0000-0001-8433-5649)
- Cédric Lorcé (ORCID: https://orcid.org/0000-0002-7091-2377)
- Ignacio Castelli
Institutions
- Centre National de la Recherche Scientifique (FR)
- École Polytechnique (FR)
- University of Pavia (IT)
- Deutsches Elektronen-Synchrotron DESY (DE)
- Thomas Jefferson National Accelerator Facility (US)
- Istituto Nazionale di Fisica Nucleare, Sezione di Pavia (IT)
- Temple University (US)
Publication Details
- Journal
- Physics Letters B
- Published
- 2024-09-06
- DOI
- https://doi.org/10.1016/j.physletb.2024.138999
- Citations
- 6
- Primary Topic
- Quantum Chromodynamics and Particle Interactions
- Type
- article
- Field-Weighted Citation Impact
- 3.96
Funders
- National Science Foundation
- U.S. Department of Energy
- California Department of Fish and Game
- Temple University
- Deutsche Forschungsgemeinschaft
- Office of Science
- Nuclear Physics