CERN Accelerating science

Article
Report number	arXiv:2002.04623
Title	Quark Flavor Phenomenology of the QCD Axion
Author(s)	Martin Camalich, Jorge (IAC, La Laguna ; Laguna U., Tenerife) ; Pospelov, Maxim (Minnesota U. ; Minnesota U., Theor. Phys. Inst.) ; Vuong, Pham Ngoc Hoa (LPSC, Grenoble) ; Ziegler, Robert (CERN ; KIT, Karlsruhe, TTP) ; Zupan, Jure (Cincinnati U.)
Publication	2020-07-28
Imprint	2020-02-11
Number of pages	24
Note	23 pages, 4 tables, 4 figures
In:	Phys. Rev. D 102 (2020) 015023
DOI	10.1103/PhysRevD.102.015023
Subject category	hep-ex ; Particle Physics - Experiment ; hep-ph ; Particle Physics - Phenomenology
Accelerator/Facility, Experiment	CERN SPS ; NA62
Abstract	Axion models with generation-dependent Peccei-Quinn charges can lead to flavor-changing neutral currents, thus motivating QCD axion searches at precision flavor experiments. We rigorously derive limits on the most general effective flavor-violating couplings from current measurements and assess their discovery potential. For two-body decays we use available experimental data to derive limits on $q\to q' a$ decay rates for all flavor transitions. Axion contributions to neutral-meson mixing are calculated in a systematic way using chiral perturbation theory and operator product expansion. We also discuss in detail baryonic decays and three-body meson decays, which can lead to the best search strategies for some of the couplings. For instance, a strong limit on the $\Lambda\to n a$ transition can be derived from the supernova SN 1987A. In the near future, dedicated searches for $q\to q' a$ decays at ongoing experiments could potentially test Peccei-Quinn breaking scales up to $10^{12}$ GeV at NA62 or KOTO, and up to $10^{9}$ GeV at Belle II or BES III.
Copyright/License	publication: © 2020-2024 authors (License: CC-BY-4.0), sponsored by SCOAP³ preprint: (License: arXiv nonexclusive-distrib 1.0)

Corresponding record in: Inspire