All Outputs (28)

Fast and accurate implementation of the effective fluid approximation for ultralight axions (2025)
Journal Article
Moss, A., Gaughan, L., & Green, A. M. (2025). Fast and accurate implementation of the effective fluid approximation for ultralight axions. Physical Review D - Particles, Fields, Gravitation and Cosmology, 111(12), Article 123530. https://doi.org/10.1103/fy1y-rjst

We present a numerically efficient and accurate implementation of the Passaglia-Hu effective fluid approximation for ultralight axions (ULAs) within the Boltzmann code CAMB. This method is specifically designed to evolve the axion field accurately ac... Read More about Fast and accurate implementation of the effective fluid approximation for ultralight axions.

The History of Primordial Black Holes (2025)
Book Chapter
Carr, B. J., & Green, A. M. (2025). The History of Primordial Black Holes. In C. Byrnes, G. Franciolini, T. Harada, P. Pani, & M. Sasaki (Eds.), Primordial Black Holes. Springer. https://doi.org/10.1007/978-981-97-8887-3_1

We overview the history of primordial black hole (PBH) research from the first papers around 50 years ago to the present epoch. The history may be divided into four periods, the dividing lines being marked by three key developments: inflation on the... Read More about The History of Primordial Black Holes.

Primordial black hole stellar microlensing constraints: understanding their dependence on the density and velocity distributions (2025)
Journal Article
Green, A. M. (2025). Primordial black hole stellar microlensing constraints: understanding their dependence on the density and velocity distributions. Journal of Cosmology and Astroparticle Physics, 2025(04), 023. https://doi.org/10.1088/1475-7516/2025/04/023

Microlensing surveys of stars in the Large Magellanic Cloud constrain the fraction of the Milky Way halo in Primordial Black Holes (PBHs) with mass 10^−9 < M/M⊙ < 10^4. Various studies have reached different conclusions on the uncertainties in these c... Read More about Primordial black hole stellar microlensing constraints: understanding their dependence on the density and velocity distributions.

How open is the asteroid-mass primordial black hole window? (2024)
Journal Article
Gorton, M., & Green, A. M. (2024). How open is the asteroid-mass primordial black hole window?. SciPost Physics, 17(2), Article 032. https://doi.org/10.21468/SciPostPhys.17.2.032

Primordial black holes (PBHs) can make up all of the dark matter (DM) if their mass, m, is in the so-called “asteroid-mass window”, 10^{17} g ≲ m ≲ 10^{22} g1017g≲m≲1022g. Observational constraints on the abundance of PBHs are usually calculated assu... Read More about How open is the asteroid-mass primordial black hole window?.

Primordial black holes as a dark matter candidate - a brief overview (2024)
Journal Article
Green, A. M. (2024). Primordial black holes as a dark matter candidate - a brief overview. Nuclear Physics B, 1003, Article 116494. https://doi.org/10.1016/j.nuclphysb.2024.116494

Historically the most popular dark matter candidates have been new elementary particles, such as Weakly Interacting Massive Particles and axions. However Primordial Black Holes (PBHs), black holes formed from overdensities in the early Universe, are... Read More about Primordial black holes as a dark matter candidate - a brief overview.

Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements (2023)
Journal Article
Mishra, S. S., Copeland, E. J., & Green, A. M. (2023). Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements. Journal of Cosmology and Astroparticle Physics, 2023(September 2023), Article 005. https://doi.org/10.1088/1475-7516/2023/09/005

Primordial Black Holes (PBHs) may form in the early Universe, from the grav-itational collapse of large density perturbations, generated by large quantum fluctuations during inflation. Since PBHs form from rare over-densities, their abundance is sens... Read More about Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements.

Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements (2023)
Journal Article
Mishra, S. S., Copeland, E. J., & Green, A. M. (2023). Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements. Journal of Cosmology and Astroparticle Physics, 2023(09), Article 005. https://doi.org/10.1088/1475-7516/2023/09/005

Primordial Black Holes (PBHs) may form in the early Universe, from the gravitational collapse of large density perturbations, generated by large quantum fluctuations during inflation. Since PBHs form from rare over-densities, their abundance is sensi... Read More about Primordial black holes and stochastic inflation beyond slow roll. Part I. Noise matrix elements.

Modelling uncertainties in wide binary constraints on primordial black holes (2023)
Journal Article
Tyler, E., Green, A. M., & Goodwin, S. P. (2023). Modelling uncertainties in wide binary constraints on primordial black holes. Monthly Notices of the Royal Astronomical Society, 524(2), 3052–3059. https://doi.org/10.1093/mnras/stad2028

Dark matter in the form of compact objects with mass Mco ≳ 10 M⊙ can be constrained by its dynamical effects on wide binary stars. Motivated by the recent interest in primordial black hole dark matter, we revisit the theoretical modelling involved in... Read More about Modelling uncertainties in wide binary constraints on primordial black holes.

Effect of clustering on primordial black hole microlensing constraints (2022)
Journal Article
Gorton, M., & Green, A. M. (2022). Effect of clustering on primordial black hole microlensing constraints. Journal of Cosmology and Astroparticle Physics, 2022(08), Article 035. https://doi.org/10.1088/1475-7516/2022/08/035

Stellar microlensing observations tightly constrain compact object dark matter in the mass range (10-11-103)M ⊙. Primordial Black Holes (PBHs) form clusters, and it has been argued that these microlensing constraints are consequently weakened or evad... Read More about Effect of clustering on primordial black hole microlensing constraints.

Direct detection of dark matter - APPEC committee report (2022)
Journal Article
Billard, J., Boulay, M., Cebrián, S., Covi, L., Fiorillo, G., Green, A., Kopp, J., Majorovits, B., Palladino, K., Petricca, F., Roszkowski, L., & Schumann, M. (2022). Direct detection of dark matter - APPEC committee report. Reports on Progress in Physics, 85(5), Article 056201. https://doi.org/10.1088/1361-6633/ac5754

This report provides an extensive review of the experimental programme of direct detection searches of particle dark matter. It focuses mostly on European efforts, both current and planned, but does it within a broader context of a worldwide activity... Read More about Direct detection of dark matter - APPEC committee report.

Dark matter in astrophysics/cosmology (2022)
Journal Article
Green, A. M. (2022). Dark matter in astrophysics/cosmology. SciPost Physics Lecture Notes, https://doi.org/10.21468/SciPostPhysLectNotes.37

These lecture notes aim to provide an introduction to dark matter from the perspective of astrophysics/cosmology. We start with a rapid overview of cosmology, including the evolution of the Universe, its thermal history and structure formation. Then... Read More about Dark matter in astrophysics/cosmology.

Primordial Black Holes as a dark matter candidate (2020)
Journal Article
Green, A. M., & Kavanagh, B. J. (2021). Primordial Black Holes as a dark matter candidate. Journal of Physics G: Nuclear and Particle Physics, 48(4), Article 043001. https://doi.org/10.1088/1361-6471/abc534

The detection of gravitational waves from mergers of tens of Solar mass black hole binaries has led to a surge in interest in Primordial Black Holes (PBHs) as a dark matter candidate. We aim to provide a (relatively) concise overview of the status of... Read More about Primordial Black Holes as a dark matter candidate.

Constraints on the cosmic string loop collapse fraction from primordial black holes (2020)
Journal Article
James-Turner, C., Weil, D. P. B., Green, A. M., & Copeland, E. J. (2020). Constraints on the cosmic string loop collapse fraction from primordial black holes. Physical Review D, 101(12), Article 123526. https://doi.org/10.1103/physrevd.101.123526

A small fraction, f , of cosmic string loops can collapse to form Primordial Black Holes (PBHs). Constraints on the abundance of PBHs can therefore be used to constrain f. We update these calculations, taking into account the PBH extended mass functi... Read More about Constraints on the cosmic string loop collapse fraction from primordial black holes.

Understanding the suppression of structure formation from dark matter-dark energy momentum coupling (2020)
Journal Article
Chamings, F. N., Avgoustidis, A., Copeland, E. J., Green, A. M., & Pourtsidou, A. (2020). Understanding the suppression of structure formation from dark matter-dark energy momentum coupling. Physical Review D, 101(4), https://doi.org/10.1103/physrevd.101.043531

Models in which scalar field dark energy interacts with dark matter via a pure momentum coupling have previously been found to potentially ease the structure formation tension between early-and late-universe observations. In this article we explore t... Read More about Understanding the suppression of structure formation from dark matter-dark energy momentum coupling.

Early dark energy constraints on growing neutrino quintessence cosmologies (2019)
Journal Article
Noble Chamings, F., Avgoustidis, A., Copeland, E. J., Green, A. M., & Li, B. (2019). Early dark energy constraints on growing neutrino quintessence cosmologies. Physical Review D, 100(4), https://doi.org/10.1103/physrevd.100.043525

We investigate cosmological models in which dynamical dark energy consists of a scalar field whose present-day value is controlled by a coupling to the neutrino sector. The behavior of the scalar field depends on three functions: a kinetic function,... Read More about Early dark energy constraints on growing neutrino quintessence cosmologies.

Pitfalls of a power-law parametrization of the primordial power spectrum for primordial black hole formation (2018)
Journal Article
Green, A. M. (2018). Pitfalls of a power-law parametrization of the primordial power spectrum for primordial black hole formation. Physical Review D, 98(2), https://doi.org/10.1103/PhysRevD.98.023529

Primordial Black Holes (PBHs) can form in the radiation dominated early Universe from the collapse of large density perturbations produced by inflation. A power-law parameterisation of the primordial power spectrum is often used to extrapolate from c... Read More about Pitfalls of a power-law parametrization of the primordial power spectrum for primordial black hole formation.

Time-integrated directional detection of dark matter (2017)
Journal Article
O'Hare, C. A., Kavanagh, B. J., & Green, A. M. (in press). Time-integrated directional detection of dark matter. Physical Review D, 96, https://doi.org/10.1103/PhysRevD.96.083011

The analysis of signals in directional dark matter (DM) detectors typically assumes that the directions of nuclear recoils can be measured in the Galactic rest frame. However, this is not possible with all directional detection technologies. In nucle... Read More about Time-integrated directional detection of dark matter.

Astrophysical uncertainties on stellar microlensing constraints on multi-solar mass primordial black hole dark matter (2017)
Journal Article
Green, A. M. (2017). Astrophysical uncertainties on stellar microlensing constraints on multi-solar mass primordial black hole dark matter. Physical Review D, 96, Article 043020. https://doi.org/10.1103/PhysRevD.96.043020

There has recently been interest in multi-Solar mass Primordial Black Holes (PBHs) as a dark matter (DM) candidate. There are various microlensing, dynamical and accretion constraints on the abundance of PBHs in this mass range. Taken at face value t... Read More about Astrophysical uncertainties on stellar microlensing constraints on multi-solar mass primordial black hole dark matter.

Astrophysical uncertainties on the local dark matter distribution and direct detection experiments (2017)
Journal Article
Green, A. M. (2017). Astrophysical uncertainties on the local dark matter distribution and direct detection experiments. Journal of Physics G: Nuclear and Particle Physics, 44(8), https://doi.org/10.1088/1361-6471/aa7819

The differential event rate in weakly interacting massive particle (WIMP) direct detection experiments depends on the local dark matter density and velocity distribution. Accurate modelling of the local dark matter distribution is therefore required... Read More about Astrophysical uncertainties on the local dark matter distribution and direct detection experiments.

Axion astronomy with microwave cavity experiments (2017)
Journal Article
O'Hare, C. A., & Green, A. M. (2017). Axion astronomy with microwave cavity experiments. Physical Review D, 95(6), Article 063017. https://doi.org/10.1103/PhysRevD.95.063017

Terrestrial searches for the conversion of dark matter axions or axion-like particles into photons inside magnetic fields are sensitive to the phase space structure of the local Milky Way halo. We simulate signals in a hypothetical future experiment... Read More about Axion astronomy with microwave cavity experiments.