Related papers: Enhanced Radiation ? from (Super) Conductor by Dar…
We have proposed a method for the detection of dark matter axion. It uses superconductor under strong magnetic field. As is well known, the dark matter axion induces oscillating electric field under magnetic field. The electric field is…
We have shown a new production mechanism of radiations produced by dark matter axion $a(t)$ under strong magnetic field $B$. The axion generates oscillating electric current in the surface of conductor. The current is extremely enhanced…
We propose a method for searching dark matter axion in axion-photon conversion. We consider a superconductor of cylindrical shape under strong magnetic field. The dark matter axion generates oscillating electric field which induces…
Axions are a theoretically promising dark matter (DM) candidate. In the presence of radiation from bright astrophysical sources at radio frequencies, nonrelativistic DM axions can undergo stimulated decay to two nearly back-to-back photons,…
We discuss a possible principle for detecting dark matter axions in galactic halos. If axions constitute a condensate in the Milky Way, stimulated emissions of the axions from a type of excitation in condensed matter can be detectable. We…
Axion dark matter (DM) produces echo images of bright radio sources via stimulated decay. These images appear as a faint radio line centered at half the axion mass, with the line width set by the DM velocity dispersion. Due to the…
In the framework of axion-gauge fields models, primordial gravitational wave perturbations could be generated during the inflationary epoch from not only the quantum fluctuation of gravitons but also the dynamics of hidden gauge fields…
Time dependent magnetic fields can be sourced by spinning neutron stars, orbiting binaries and merging neutron stars. We consider electromagnetic radiation from axion condensates in the background of an alternating magnetic field. We find…
We derive the electric current on surface of a normal metal or superconductor induced by the light bosonic dark matter, such as axion or hidden photon, by appropriately taking account of the boundary condition of the electric and magnetic…
We argue that dark radiation is naturally generated from the decay of the overall volume modulus in the LARGE volume scenario. We consider both sequestered and non-sequestered cases, and find that the axionic superpartner of the modulus is…
We study the direct radiation excited by oscillating axion (or axion-like particle) dark matter in a homogenous magnetic field and its detection scheme. We concretely derive the analytical expression of the axion-induced radiated power for…
It was recently shown that a powerful beam of radio/microwave radiation sent out to space can produce detectable back-scattering via the stimulated decay of ambient axion dark matter. This echo is a faint and narrow signal centered at an…
We investigate a novel technique for the astrophysical detection of axions or axion-like particles in the dark matter halo of the Milky Way based on stimulated decay of axions, which we call axion gegenschein emission. Photons from the…
Current observations of the cosmic microwave background could confirm an increase in the radiation energy density after primordial nucleosynthesis but before photon decoupling. We show that, if the gravitino problem is solved by a light…
Relativistic axions are good candidates for the dark radiation for which there are mounting observational hints. The primordial decays of heavy fields produce axions which are ultra-energetic compared to thermalised matter and inelastic…
Recently, two of the present authors showed that even when the axion momentum is much smaller than its mass, the axion can still behave like radiation if its energy density greatly exceeds the maximum potential energy set by the cosine-type…
An axion rotating in field space can produce dark photons in the early universe via tachyonic instability. This explosive particle production creates a background of stochastic gravitational waves that may be visible at pulsar timing arrays…
When ultralight axion dark matter encounters a static magnetic field, it sources an effective electric current that follows the magnetic field lines and oscillates at the axion Compton frequency. We propose a new experiment to detect this…
It is well known that an accelerated charged particle radiates away energy. However, whether an accelerated neutral composite particle radiates away energy is unclear. We study decoherent Larmor radiation from an accelerated neutral…
Recently the EDGES experiment reported an enhanced 21cm absorption signal in the radio wave observation, which may be interpreted as either anomalous cooling of baryons or heating of cosmic microwave background photons. In this paper, we…