Saved in:
Bibliographic Details
Main Author: Bisal, Subhadip
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2507.12570
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909703054819328
author Bisal, Subhadip
author_facet Bisal, Subhadip
contents The couplings of axion-like particles (ALPs) to Standard Model fermions are proportional to the fermion masses, making the interaction with the top quark particularly significant. In this study, we consider an ALP that is a mixture of CP-even and CP-odd components, thereby introducing CP violation. This CP violation, in turn, gives rise to electric dipole moments (EDMs) of quarks and leptons, as well as chromoelectric dipole moments (CEDMs) of quarks. We compute the one-loop and two-loop contributions to the top quark CEDM induced by the ALP. In our calculation, we treat the external gluon as off-shell with momentum $q^2 \neq 0$, derive the analytical results, and finally evaluate the top quark CEDM at $q^2 = m_t^2$, corresponding to the top quark pole mass. This value is relevant for subsequent calculations of the EDMs of the neutron and mercury. By applying current experimental bounds on EDMs and CEDMs, we derive constraints on the ALP-top quark coupling, with the strongest limit coming from the neutron EDM.
format Preprint
id arxiv_https___arxiv_org_abs_2507_12570
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Constraining ALP-Top Interaction from the Chromoelectric Dipole Moment of the Top Quark
Bisal, Subhadip
High Energy Physics - Phenomenology
The couplings of axion-like particles (ALPs) to Standard Model fermions are proportional to the fermion masses, making the interaction with the top quark particularly significant. In this study, we consider an ALP that is a mixture of CP-even and CP-odd components, thereby introducing CP violation. This CP violation, in turn, gives rise to electric dipole moments (EDMs) of quarks and leptons, as well as chromoelectric dipole moments (CEDMs) of quarks. We compute the one-loop and two-loop contributions to the top quark CEDM induced by the ALP. In our calculation, we treat the external gluon as off-shell with momentum $q^2 \neq 0$, derive the analytical results, and finally evaluate the top quark CEDM at $q^2 = m_t^2$, corresponding to the top quark pole mass. This value is relevant for subsequent calculations of the EDMs of the neutron and mercury. By applying current experimental bounds on EDMs and CEDMs, we derive constraints on the ALP-top quark coupling, with the strongest limit coming from the neutron EDM.
title Constraining ALP-Top Interaction from the Chromoelectric Dipole Moment of the Top Quark
topic High Energy Physics - Phenomenology
url https://arxiv.org/abs/2507.12570