Related papers: Monodromic transparency of axion domain walls
We present a brief overview of the ongoing searches for the axion particle via its coupling to photons. Both the classical QCD axions and more recently proposed Axion-Like-Particles are considered. Astrophysical bounds on the axion-photon…
Current techniques cannot detect axion dark matter over much of its parameter space, particularly in the theoretically well-motivated region where the axion decay constant f_a lies near the GUT and Planck scales. We suggest a novel…
We analyze the most salient cosmological features of axions in extensions of the Standard Model with a gauged anomalous extra U(1) symmetry. The model is built by imposing the constraint of gauge invariance in the anomalous effective…
We present a new mechanism to deplete the energy density of the QCD axion, making decay constants as high as $f_a \simeq 10^{17}\,\rm{GeV}$ viable for generic initial conditions. In our setup, the axion couples to a massless dark photon…
The QCD axion's coupling to photons is often assumed to lie in a narrow band as a function of the axion mass. We demonstrate that several simple mechanisms, in addition to the photophilic clockwork axion already in the literature, can…
The presence of axions introduces new diagrams at one-loop order to the two-photon decays of the neutral pion through axion-pion mixing. In this work, we calculate this correction, missing in all current calculations, in the framework of…
We study $SU(N_c)$ gauge theories with Dirac fermions in representations ${\cal{R}}$ of nonzero $N$-ality, coupled to axions. These theories have an exact discrete chiral symmetry, which has a mixed 't Hooft anomaly with general…
Recently there has been interest in the physical properties of dark matter axion condensates. Due to gravitational attraction and self-interactions, they can organize into spatial localized clumps, whose properties were examined by us in…
The effects of the axion field have been widely studied in theoretical physics, particularly in particle physics. Considering the phase synchronization and the mean free path of the axion, the bulk of the phase coherent superconductor is…
Pseudoscalar particles, with almost zero mass and very weak coupling to the visible matter, arise in many extensions of the standard model of particle physics. Their mixing with photons in the presence of an external magnetic field leads to…
We investigate the distribution of an interacting axion-like massive field within a magnetized Neutron Star. For this we consider the effect of an intense density-dependent axially symmetric stellar magnetic field ${\bf B}(r,\theta)$ adding…
We study the QCD axion arising from the 5th component of a bulk $U(1)$ gauge field in a five-dimensional warped grand unified theory, and determine the viable range of the axion decay constant $f_a$. Unlike flat extra dimensions, where…
We argue that there are both experimental and theoretical reasons to reconsider the construction of KSVZ-like axion models. From the experimental side, predictions for the axion-photon coupling are not consistent with the collection of…
We perform an updated analysis on a long-lived axion domain wall (DW) network. By simulating the axion field on a 3D lattice and fitting an analytical model for the DW evolution, we identify the leading energy loss mechanisms of the DWs and…
In interstellar media characterized by a nonrelativistic plasma of electrons and heavy ions, we study the effect of axion dark matter coupled to photons on the dynamics of an electric field. In particular, we assume the presence of a…
Wave propagation in periodically time-dependent media can exhibit driven mode conversion that is absent in static or adiabatic descriptions. We show that photon propagation through a coherent axion dark matter background provides a natural…
The QCD axion is a well-motivated hypothetical particle beyond the Standard Model (SM) and a compelling dark matter candidate. Its relic abundance is highly sensitive to the thermal history of the universe when the temperature is around the…
In this proceedings article we present a selected set of our lattice results regarding the effect that background electromagnetic fields have on the topology of QCD. In particular, we report on the lattice spacing-dependence of the…
We consider the coupling of axions to gauge bosons in higher-dimensional Grand Unified Theories (GUT) inspired by string theory constructions with D-branes on orbifold singularities, the so-called orbifold GUTs. Due to their topological…
Non-relativistic QCD axions or axion-like particles are among the most popular candidates for cold Dark Matter (DM) in the universe. We proposed to detect axion-like DM, using linearly polarized pulsar light as a probe. Because of…