Related papers: Review on Axions
Axion-like particles (ALPs) are good candidates for mediators to the dark sector. We explore scenarios in which an ALP mediates interactions between dark matter and electroweak gauge bosons. These models yield testable electromagnetic…
Searches for dark matter (DM) constituents are presently mainly focused on axions and WIMPs despite the fact that far higher mass constituents are viable. We discuss and dispute whether axions exist and those arguments for WIMPs which arise…
Although the axion is the most compelling solution to the strong CP problem, the ad hoc introduced global Peccei-Quinn symmetry suffers from a severe fine-tuning problem known as the quality problem. In this Letter, we show that the…
The QCD axion or axion-like particles are candidates of dark matter of the universe. On the other hand, axion-like excitations exist in certain condensed matter systems, which implies that there can be interactions of dark matter particles…
Hidden axions may be coupled to the standard model particles through a kinetic or mass mixing with QCD axion. We study a scenario in which a hidden axion constitutes a part of or the whole of dark matter and decays into photons through the…
Axions, originally proposed to solve the strong CP problem of quantum chromodynamics, emerge now as leading candidates of WISP dark matter. The rich phenomenology associated to the light and stable QCD axion can be described as an effective…
Light axion-like particles occur in many theories of beyond-Standard-Model physics, and may make up some or all of the universe's dark matter. One of the ways they can couple to the Standard Model is through the electromagnetic $F_{\mu\nu}…
We explore whether the axion which solves the strong CP problem can naturally be much lighter than the canonical QCD axion. The $Z_\mathcal{N}$ symmetry proposed by Hook, with $\mathcal{N}$ mirror and degenerate worlds coexisting in Nature…
The invisible axion is a well-motivated hypothetical particle which could address two fundamental questions in modern physics - the CP symmetry problem in the strong interactions and the dark matter mystery of our universe. The plausible…
The dark photon is a massive hypothetical particle that interacts with the Standard Model by kinetically mixing with the visible photon. For small values of the mixing parameter, dark photons can evade cosmological bounds to be a viable…
Hidden monopole is a plausible dark matter candidate due to its stability, but its direct experimental search is extremely difficult due to feeble interactions with the standard model particles in the minimal form. Then, we introduce an…
We propose a minimal extension of the standard model which includes only one additional complex scalar field, flavon, with flavor-dependent global U(1) symmetry. It not only explains the hierarchical flavor structure in the quark and lepton…
If QCD axions form a large fraction of the total mass of dark matter, then axion stars could be very abundant in galaxies. As a result, collisions with each other, and with other astrophysical bodies, can occur. We calculate the rate and…
Exploring the mysterious dark matter is a key quest in modern physics. Currently, detecting axions, a hypothetical particle proposed as a primary component of dark matter, remains a significant challenge due to their weakly interacting…
The Strong CP Problem can be resolved by introducing an additional global symmetry known as Peccei-Quinn symmetry. Once PQ symmetry is broken the associated particle, the QCD axion, is a plausible dark matter candidate. Calculating the…
Axion dark matter can satisfy the conditions needed to account for all of the dark matter and solve the strong CP problem. The Axion Dark Matter eXperiment (ADMX) is a direct dark matter search using a haloscope to convert axions to photons…
The axion is an unusually well motivated dark matter candidate which is the Goldstone Boson associated with spontaneous breaking of the PQ symmetry of QCD. I describe an experiment to search for axions in our Galactic halo using a high Q…
The next generation of axion direct detection experiments may rule out or confirm axions as the dominant source of dark matter. We develop a general likelihood-based framework for studying the time-series data at such experiments, with a…
The axion or axion-like particle motivated from a natural solution of strong CP problem or string theory is a promising dark matter candidate. We study the new observational effects of ultralight axion-like particles by the space-borne…
Axion-like particles (ALPs) can provide a portal to new states of a dark sector. We study the phenomenology of this portal when the ALP mainly decays invisibly, while its interaction with the standard model sector proceeds essentially via…