Light weakly coupled axial forces: models, constraints, and projections
Abstract
Here, we investigate the landscape of constraints on MeVGeV scale, hidden U(1) forces with nonzero axialvector couplings to Standard Model fermions. While the purely vectorcoupled dark photon, which may arise from kinetic mixing, is a wellmotivated scenario, several MeVscale anomalies motivate a theory with axial couplings which can be UVcompleted consistent with Standard Model gauge invariance. Moreover, existing constraints on dark photons depend on products of various combinations of axial and vector couplings, making it difficult to isolate the e ects of axial couplings for particular flavors of SM fermions. We present a representative renormalizable, UVcomplete model of a dark photon with adjustable axial and vector couplings, discuss its general features, and show how some UV constraints may be relaxed in a model with nonrenormalizable Yukawa couplings at the expense of finetuning. We survey the existing parameter space and the projected reach of planned experiments, brie y commenting on the relevance of the allowed parameter space to lowenergy anomalies in π ^{0} and ^{8}Be* decay.
 Authors:
 Publication Date:
 Research Org.:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 OSTI Identifier:
 1345639
 Report Number(s):
 FERMILABPUB16385PPD; UCIHEPTR201615; MITP16098; PUPT2507; arXiv:1609.09072
Journal ID: ISSN 10298479; 1488576
 Grant/Contract Number:
 AC0207CH11359
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 5; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Beyond Standard Model; gauge symmetry
Citation Formats
Kahn, Yonatan, Krnjaic, Gordan, MishraSharma, Siddharth, and Tait, Tim M. P.. Light weakly coupled axial forces: models, constraints, and projections. United States: N. p., 2017.
Web. doi:10.1007/JHEP05(2017)002.
Kahn, Yonatan, Krnjaic, Gordan, MishraSharma, Siddharth, & Tait, Tim M. P.. Light weakly coupled axial forces: models, constraints, and projections. United States. doi:10.1007/JHEP05(2017)002.
Kahn, Yonatan, Krnjaic, Gordan, MishraSharma, Siddharth, and Tait, Tim M. P.. Mon .
"Light weakly coupled axial forces: models, constraints, and projections". United States.
doi:10.1007/JHEP05(2017)002. https://www.osti.gov/servlets/purl/1345639.
@article{osti_1345639,
title = {Light weakly coupled axial forces: models, constraints, and projections},
author = {Kahn, Yonatan and Krnjaic, Gordan and MishraSharma, Siddharth and Tait, Tim M. P.},
abstractNote = {Here, we investigate the landscape of constraints on MeVGeV scale, hidden U(1) forces with nonzero axialvector couplings to Standard Model fermions. While the purely vectorcoupled dark photon, which may arise from kinetic mixing, is a wellmotivated scenario, several MeVscale anomalies motivate a theory with axial couplings which can be UVcompleted consistent with Standard Model gauge invariance. Moreover, existing constraints on dark photons depend on products of various combinations of axial and vector couplings, making it difficult to isolate the e ects of axial couplings for particular flavors of SM fermions. We present a representative renormalizable, UVcomplete model of a dark photon with adjustable axial and vector couplings, discuss its general features, and show how some UV constraints may be relaxed in a model with nonrenormalizable Yukawa couplings at the expense of finetuning. We survey the existing parameter space and the projected reach of planned experiments, brie y commenting on the relevance of the allowed parameter space to lowenergy anomalies in π0 and 8Be* decay.},
doi = {10.1007/JHEP05(2017)002},
journal = {Journal of High Energy Physics (Online)},
number = 5,
volume = 2017,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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