Related papers: The Monodromic Axion-Photon Coupling
An interaction of a pseudoscalar particle with two photons induced by an external electromagnetic field is used to study the photon decay $\gamma \to \gamma a$ where a is a pseudoscalar particle associated with the Peccei-Quinn U(1)…
We show that photons with energies above the GZK cutoff can reach us from very distant sources if they mix with light axions in extragalactic magnetic fields. The effect which enables this is the conversion of photons into axions, which are…
In the framework of Einstein-Maxwell-axion theory we consider static spherically symmetric solutions, which describe a magnetic monopole in the axionic environment. These solutions are interpreted as the solutions for an axionic dyon, the…
Axion-like particles (ALPs) and photons can quantum mechanically interconvert when propagating through magnetic fields, and ALP-photon conversion may induce oscillatory features in the spectra of astrophysical sources. We use deep (370 ks),…
String theory axions are interesting candidates for fields whose potential might be controllable over super-Planckian field ranges and therefore as possible candidates for inflatons in large field inflation. Axion monodromy scenarios are…
Axions are hypothetical particles, proposed to account for the invariance of CP symmetry in quantum chromodynamics. While axions and axion-like-particles are well-motivated by string theory and beyond-Standard-Model extensions, they have…
We consider an enlarged color sector which solves the strong CP problem via new massless fermions. The spontaneous breaking of a unified color group into QCD and another confining group provides a source of naturally large axion mass $m_a$…
The interaction between the dark/mirror sector and the ordinary sector is considered, where the two sectors interact with each other by sharing the same QCD axion field. This feature makes the mixing between ordinary and dark/mirror photons…
One of the promising new proposals to search for axions in astrophysical environments is to look for narrow radio lines produced from the resonant conversion of axion dark matter falling through the magnetospheres of neutron stars. For…
We show how the properties of the QCD axion change in systems at finite baryonic density, such as neutron stars. At nuclear saturation densities, where corrections can be reliably computed, we find a mild reduction of the axion mass and up…
A general scheme for axion electrodynamics is given, in which a surrounding medium of constant permittivity and permeability is assumed. Then, as an application we give simple numerical estimates for the electromagnetic current density…
We investigate the dynamics of axion-like particle (ALP) dark matter where the field range is enlarged by a monodromy. The monodromy potential allows sufficient production of dark matter also at larger couplings to the Standard Model…
Axions are a well-motivated dark matter candidate. They may be detectable from radio line emission due to resonant conversion in neutron star magnetospheres. While radio data collection for this signal has begun, further efforts are…
We consider the axion field and electromagnetic waves with rapid time dependence, coupled to a strong time independent, asymptotically approaching a constant at infinity "mean" magnetic field, which takes into account the back reaction from…
The introduction of axions gives rise to additional one-loop diagrams for the two-photon decays of neutral pions via axion-pion mixing. We compute this correction that has been overlooked in existing calculations, within the framework of…
The main motivation for our work has been a puzzling observation concerning quasars. No one expected the existence of correlations in the polarisation of visible light coming from objects separated by gigaparsecs, until they were first…
Magnetic fields mix axions with photons, allowing for the cyclotron process e -> e + a by virtue of an intermediate plasmon even if axions do not couple to electrons at tree level. The axion and longitudinal-plasmon dispersion relations…
Axions mix with neutral pions after the QCD phase transition through their common coupling to the radiation bath via a Chern-Simons term, as a consequence of the $U(1)$ anomaly. The non-equilibrium effective action that describes this…
Axion-photon mixing has been proposed as an alternative to acceleration as the explanation for supernovae dimming. We point out that the loss of photons due to this mixing will induce a strong asymmetry between the luminosity, d_L(z), and…
We study higher-form symmetries and a higher group in the low energy limit of a $(3+1)$-dimensional axion electrodynamics with a massive axion and a massive photon. A topological field theory describing topological excitations with the…