Search Publications
Novel constraints on the particle nature of dark matter from stellar streams
Bovy, Jo; Erkal, Denis; Bertone, Gianfranco +2 more
Tidal streams are highly sensitive to perturbations from passing dark matter (DM) subhalos and thus provide a means of measuring their abundance. In a recent paper, we analyzed the distribution of stars along the GD-1 stream with a combination of data from the Gaia satellite and the Pan-STARRS survey, and we demonstrated that the population of DM …
Exploring the early Universe with Gaia and Theia
Garcia-Bellido, Juan; Murayama, Hitoshi; White, Graham
It has recently been pointed out that Gaia is capable of detecting a stochastic gravitational wave background in the sensitivity band between the frequency of pulsar timing arrays and LISA. We argue that Gaia and Theia have great potential for early universe cosmology, since such a frequency range is ideal for probing phase transitions in asymmetr…
Improved treatment of dark matter capture in white dwarfs
Bell, Nicole F.; Ramirez-Quezada, Maura E.; Busoni, Giorgio +2 more
White dwarfs, the most abundant stellar remnants, provide a promising means of probing dark matter interactions, complimentary to terrestrial searches. The scattering of dark matter from stellar constituents leads to gravitational capture, with important observational consequences. In particular, white dwarf heating occurs due to the energy transf…
Dependence of dark matter - electron scattering on the galactic dark matter velocity distribution
Radick, Aria; Taki, Anna-Maria; Yu, Tien-Tien
The rate of dark matter-electron scattering depends on the underlying velocity distribution of the dark matter halo. Importantly, dark matter-electron scattering is particularly sensitive to the high-velocity tail, which differs significantly amongst the various dark matter halo models. In this work, we summarize the leading halo models and discus…
Don't cross the streams: caustics from fuzzy dark matter
Bovy, Jo; Dalal, Neal; Hui, Lam +1 more
We study how tidal streams from globular clusters may be used to constrain the mass of ultra-light dark matter particles, called `fuzzy' dark matter (FDM). A general feature of FDM models is the presence of ubiquitous density fluctuations in bound, virialized dark matter structures, on the scale of the de Broglie wavelength, arising from wave inte…
Constraining axion-like particles using the white dwarf initial-final mass relation
Dolan, Matthew J.; Hiskens, Frederick J.; Volkas, Raymond R.
Axion-like particles (ALPs), a class of pseudoscalars common to many extensions of the Standard Model, have the capacity to drain energy from the interiors of stars. Consequently, stellar evolution can be used to derive many constraints on ALPs. We study the influence that keV-MeV scale ALPs which interact exclusively with photons can exert on the…
Testing Primordial Black Holes with multi-band observations of the stochastic gravitational wave background
García-Bellido, Juan; Kuroyanagi, Sachiko; Braglia, Matteo
The mass distribution of Primordial Black Holes (PBHs) is affected by drops in the pressure of the early Universe plasma. For example, events in the standard model of particle physics, such as the W ±/Z 0 decoupling, the quark-hadron transition, the muon and pion becoming non-relativistic, and the annihilation of electrons an…
The PAU survey: measurement of narrow-band galaxy properties with approximate bayesian computation
Tortorelli, Luca; Amara, Adam; Refregier, Alexandre +22 more
Narrow-band imaging surveys allow the study of the spectral characteristics of galaxies without the need of performing their spectroscopic follow-up. In this work, we forward-model the Physics of the Accelerating Universe Survey (PAUS) narrow-band data. The aim is to improve the constraints on the spectral coefficients used to create the galaxy sp…
Towards a more rigorous treatment of uncertainties on the velocity distribution of dark matter particles for capture in stars
Lopes, Ilídio; Lacroix, Thomas; Lopes, José
Dark matter (DM) capture in stars offers a rich phenomenology that makes it possible to probe a wide variety of particle DM scenarios in diverse astrophysical environments. In spite of decades of improvements to refine predictions of capture-related observables and better quantify astrophysical and particle-physics uncertainties, the actual impact…
Testing the predictions of axisymmetric distribution functions of galactic dark matter with hydrodynamical simulations
Lavalle, Julien; Petač, Mihael; Núñez-Castiñeyra, Arturo +1 more
Signal predictions for galactic dark matter (DM) searches often rely on assumptions regarding the DM phase-space distribution function (DF) in halos. This applies to both particle (e.g. p-wave suppressed or Sommerfeld-enhanced annihilation, scattering off atoms, etc.) and macroscopic DM candidates (e.g. microlensing of primordial black holes). As …