147 citations · 1.1k across the 30 of their papers we have counts for
14 papers · 1 filter
The phenomenology of Axion Relic Pockets
Wafaa Khater, M. C. David Marsh, Charalampos Nikolis
Axion relic pockets are phase-transition remnants consisting of regions of false vacuum stabilised from collapse by a hot axion gas. Axion relic pockets can comprise dark matter, b…
On the applicability of the Landau-Zener formula to axion-photon conversion
Pierluca Carenza, M. C. David Marsh
Axions and photons resonantly interconvert in regions where the plasma frequency approximately equals the axion mass. This process is directly analogous to an avoided level crossin…
Transient Radio Lines from Axion Miniclusters and Axion Stars
Samuel J. Witte, Sebastian Baum, Matthew Lawson +3
Gravitationally bound clumps of dark matter axions in the form of 'miniclusters' or even denser 'axion stars' can generate strong radio signals through axion-photon conversion when…
Magnetohydrodynamics predicts heavy-tailed distributions of axion-photon conversion
Pierluca Carenza, Ramkishor Sharma, M. C. David Marsh +2
The interconversion of axionlike particles (ALPs) and photons in magnetised astrophysical environments provides a promising route to search for ALPs. The strongest limits to date o…
Strong supernovae bounds on ALPs from quantum loops
Ricardo Z. Ferreira, M. C. David Marsh, Eike Müller
We show that in theories of axionlike particles (ALPs) coupled to electrons at tree-level, the one-loop effective coupling to photons is process dependent: the effective coupling r…
Do direct detection experiments constrain axionlike particles coupled to electrons?
Ricardo Z. Ferreira, M. C. David Marsh, Eike Müller
Several laboratory experiments have published limits on axionlike particles (ALPs) with feeble couplings to electrons and masses in the keV-MeV range, under the assumption that suc…
The Fourier formalism for relativistic axion-photon conversion, with astrophysical applications
M. C. David Marsh, James H. Matthews, Christopher Reynolds +1
We study the weak mixing of photons and relativistic axion-like particles (axions) in plasmas with background magnetic fields, . We show that, to leading order in the axio…
Axion-photon conversion in strongly magnetised plasmas
Alexander J. Millar, Sebastian Baum, Matthew Lawson +1
Axion dark matter can resonantly convert to photons in the magnetosphere of neutron stars, possibly giving rise to radio signals observable on Earth. This method for the indirect d…
A New Bound on Axion-Like Particles
M. C. David Marsh, Helen R. Russell, Andrew C. Fabian +3
Axion-like particles (ALPs) and photons can quantum mechanically interconvert when propagating through magnetic fields, and ALP-photon conversion may induce oscillatory features in…
Galaxy Cluster Thermal X-Ray Spectra Constrain Axion-Like Particles
Joseph P. Conlon, M. C. David Marsh, Andrew J. Powell
Axion-like particles (ALPs) and photons inter-convert in the presence of a magnetic field. At keV energies in the environment of galaxy clusters, the conversion probability can bec…
Observational consistency and future predictions for a 3.5 keV ALP to photon line
Pedro D. Alvarez, Joseph P. Conlon, Francesca V. Day +2
Motivated by the possibility of explaining the 3.5 keV line through dark matter decaying to axion-like particles that subsequently convert to photons, we study ALP-photon conversio…
The Darkness of Spin-0 Dark Radiation
M. C. David Marsh
We show that the scattering of a general spin-0 sector of dark radiation off the pre-recombination thermal plasma results in undetectably small spectral distortions of the Cosmic M…
A 3.55 keV Photon Line and its Morphology from a 3.55 keV ALP Line
Michele Cicoli, Joseph P. Conlon, M. C. David Marsh +1
Galaxy clusters can efficiently convert axion-like particles (ALPs) to photons. We propose that the recently claimed detection of a 3.55--3.57 keV line in the stacked spectra of a…
The Cosmophenomenology of Axionic Dark Radiation
Joseph P. Conlon, M. C. David Marsh
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 ultr…