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Title: The photo-philic QCD axion

Abstract

Here, we propose a framework in which the QCD axion has an exponentially large coupling to photons, relying on the “clockwork” mechanism. We discuss the impact of present and future axion experiments on the parameter space of the model. In addition to the axion, the model predicts a large number of pseudoscalars which can be light and observable at the LHC. In the most favorable scenario, axion Dark Matter will give a signal in multiple axion detection experiments and the pseudo-scalars will be discovered at the LHC, allowing us to determine most of the parameters of the model.

Authors:
 [1];  [2];  [3];  [4]
  1. Rutgers Univ., Piscataway, NJ (United States)
  2. New York Univ., New York, NY (United States)
  3. New York Univ., New York, NY (United States); Univ. of Heidelberg, Heidelberg (Germany)
  4. Univ. of Chicago, Chicago, IL (United States)
Publication Date:
Research Org.:
Rutgers Univ., Piscataway, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1366744
Grant/Contract Number:
SC0010008
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: 1; 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; CP violation

Citation Formats

Farina, Marco, Pappadopulo, Duccio, Rompineve, Fabrizio, and Tesi, Andrea. The photo-philic QCD axion. United States: N. p., 2017. Web. doi:10.1007/JHEP01(2017)095.
Farina, Marco, Pappadopulo, Duccio, Rompineve, Fabrizio, & Tesi, Andrea. The photo-philic QCD axion. United States. doi:10.1007/JHEP01(2017)095.
Farina, Marco, Pappadopulo, Duccio, Rompineve, Fabrizio, and Tesi, Andrea. Mon . "The photo-philic QCD axion". United States. doi:10.1007/JHEP01(2017)095. https://www.osti.gov/servlets/purl/1366744.
@article{osti_1366744,
title = {The photo-philic QCD axion},
author = {Farina, Marco and Pappadopulo, Duccio and Rompineve, Fabrizio and Tesi, Andrea},
abstractNote = {Here, we propose a framework in which the QCD axion has an exponentially large coupling to photons, relying on the “clockwork” mechanism. We discuss the impact of present and future axion experiments on the parameter space of the model. In addition to the axion, the model predicts a large number of pseudoscalars which can be light and observable at the LHC. In the most favorable scenario, axion Dark Matter will give a signal in multiple axion detection experiments and the pseudo-scalars will be discovered at the LHC, allowing us to determine most of the parameters of the model.},
doi = {10.1007/JHEP01(2017)095},
journal = {Journal of High Energy Physics (Online)},
number = 1,
volume = 2017,
place = {United States},
year = {Mon Jan 23 00:00:00 EST 2017},
month = {Mon Jan 23 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 7works
Citation information provided by
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  • We consider the constraints from Supernova 1987A on particles with small couplings to the Standard Model. We discuss a model with a fermion coupled to a dark photon, with various mass relations in the dark sector; millicharged particles; dark-sector fermions with inelastic transitions; the hadronic QCD axion; and an axion-like particle that couples to Standard Model fermions with couplings proportional to their mass. In the fermion cases, we develop a new diagnostic for assessing when such a particle is trapped at large mixing angles. Our bounds for a fermion coupled to a dark photon constrain small couplings and masses <200more » MeV, and do not decouple for low fermion masses. They exclude parameter space that is otherwise unconstrained by existing accelerator-based and direct-detection searches. In addition, our bounds are complementary to proposed laboratory searches for sub-GeV dark matter, and do not constrain several "thermal" benchmark-model targets. For a millicharged particle, we exclude charges between 10^(-9) to a few times 10^(-6) in units of the electron charge; this excludes parameter space to higher millicharges and masses than previous bounds. For the QCD axion and an axion-like particle, we apply several updated nuclear physics calculations and include the energy dependence of the optical depth to accurately account for energy loss at large couplings. We rule out a hadronic axion of mass between 0.1 and a few hundred eV, or equivalently bound the PQ scale between a few times 10^4 and 10^8 GeV, closing the hadronic axion window. For an axion-like particle, our bounds disfavor decay constants between a few times 10^5 GeV up to a few times 10^8 GeV. In all cases, our bounds differ from previous work by more than an order of magnitude across the entire parameter space. We also provide estimated systematic errors due to the uncertainties of the progenitor.« less
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