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Title: Light weakly coupled axial forces: models, constraints, and projections

Abstract

Here, we investigate the landscape of constraints on MeV-GeV scale, hidden U(1) forces with nonzero axial-vector couplings to Standard Model fermions. While the purely vector-coupled dark photon, which may arise from kinetic mixing, is a well-motivated scenario, several MeV-scale anomalies motivate a theory with axial couplings which can be UV-completed 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, UV-complete 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 fine-tuning. 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 low-energy anomalies in π 0 and 8Be* 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) (SC-25)
OSTI Identifier:
1345639
Report Number(s):
FERMILAB-PUB-16-385-PPD; UCI-HEP-TR-2016-15; MITP-16-098; PUPT-2507; arXiv:1609.09072
Journal ID: ISSN 1029-8479; 1488576
Grant/Contract Number:
AC02-07CH11359
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 1029-8479
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, Mishra-Sharma, 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, Mishra-Sharma, 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, Mishra-Sharma, 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 Mishra-Sharma, Siddharth and Tait, Tim M. P.},
abstractNote = {Here, we investigate the landscape of constraints on MeV-GeV scale, hidden U(1) forces with nonzero axial-vector couplings to Standard Model fermions. While the purely vector-coupled dark photon, which may arise from kinetic mixing, is a well-motivated scenario, several MeV-scale anomalies motivate a theory with axial couplings which can be UV-completed 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, UV-complete 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 fine-tuning. 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 low-energy 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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Cited by: 11works
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