Related papers: Guidelines for axion identification in astrophysic…
Magnetic field dependent transient solar observations are suggestive for axion-photon oscillations with light axion(-like) particle involvement. Novel dark-moon measurements with the SMART X-ray detectors can be conclusive for radiatively…
The working principle of axion helioscopes can be behind unexpected solar X-ray emission, being associated with solar magnetic fields, which become the catalyst. Solar axion signals can be transient brightenings as well as continuous…
Unexpected astrophysical observations can be explained by gravitationally captured massive particles, which are produced inside the Sun or other Stars and are accumulated over cosmic times. Their radiative decay in solar outer space would…
Many theoretically well-motivated extensions of the Standard Model of particle physics predict the existence of the axion and further ultralight axion-like particles. They may constitute the mysterious dark matter in the universe and solve…
Axions and axion like particles in general are consequences of the extensions of the standard model in particle physics. Axions have been proposed as hypothetical pseudo-scalar particles in particle physics to solve the strong Charge-Parity…
Orbiting $\gamma$-detectors combined with the magnetic field of the Earth or the Sun can work parasitically as cosmic axion telescopes. The relatively short field lengths allow the axion-to-photon conversion to be coherent for $m_{axion}…
The axion has emerged in recent years as a leading particle candidate to provide the mysterious dark matter in the cosmos, as we review here for a general scientific audience. We describe first the historical roots of the axion in the…
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…
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…
The axion solution of the strong CP problem provides a number of possible windows to physics beyond the standard model, notably in the form of searches for solar axions and for galactic axion dark matter, but in a broader context also…
Axions seem ubiquitous in string theories and some of them may be produced non-thermally by heavy scalar decays, contributing to dark radiation. We study various cosmological effects of photons produced from the axionic dark radiation…
Axions and other very light axion-like particles appear in many extensions of the Standard Model, and are leading candidates to compose part or all of the missing matter of the Universe. They also appear in models of inflation, dark…
Axions generated thermally in the solar core can convert nearly directly to X-rays as they pass through the solar atmosphere via interaction with the magnetic field. The result of this conversion process would be a diffuse…
Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting…
The soft X-ray flux produced by solar axions in the Earth's magnetic field is evaluated in the context of ESA's XMM-Newton observatory. Recent calculations of the scattering of axion-conversion X-rays suggest that the sunward magnetosphere…
Axionlike particles (ALPs) are a common prediction of theories beyond the Standard Model of particle physics that could explain the entirety of the cold dark matter. These particles could be detected through their mixing with photons in…
The investigation on the production of particles in slowly varying but extremely intense magnetic field in extended to the case of axions. The motivation is, as for some previously considered cases, the possibility that such kind of…
We give detailed predictions for the spectral signatures arising from photon-particle oscillations in astrophysical objects. The calculations include quantum electrodynamic effects as well as those due to active relativistic plasma. We show…
Axion-like particles are hypothetical new light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the…
The particle that makes up the dark matter of the universe could be an axion or axion-like particle. A collection of axions can condense into a bound Bose-Einstein condensate called an axion star. It is possible that a significant fraction…