Investigating dark matter substructure with pulsar timing: II. Improved limits on small-scale cosmology

Abstract

Ultracompact Minihalos (UCMHs) have been proposed as a type of dark matter sub-structure seeded by large-amplitude primordial perturbations and topological defects. UCMHs are expected to survive to the present era, allowing constraints to be placed on their cosmic abundance using observations within our own Galaxy. Constraints on their number density can be linked to conditions in the early universe that impact structure formation, such as increased primordial power on small scales, generic weak non-Gaussianity, and the presence of cosmic strings. We use new constraints on the abundance of UCMHs from pulsar timing to place generalised limits on the parameters of each of these cosmological scenarios. At some scales, the limits are the strongest to date, exceeding those from dark matter annihilation. Our new limits have the added advantage of being independent of the particle nature of dark matter, as they are based only on gravitational effects.

13 pages, 10 figures, includes erratum published in MNRAS

References in corpus (10)

• Effects of Scale-Dependent Non-Gaussianity on Cosmological Structures
• Generalised constraints on the curvature perturbation from primordial black holes
• Observable Spectra of Induced Gravitational Waves from Inflation
• Signatures of non-gaussianity in the isocurvature modes of primordial black hole dark matter
• Remnants of dark matter clumps
• Gamma-rays from ultracompact minihalos: potential constraints on the primordial curvature perturbation
• Investigating dark matter substructure with pulsar timing: I. Constraints on ultracompact minihalos
• The long-short wavelength mode coupling tightens primordial black hole constraints
• Constraints on cosmic strings from ultracompact minihalos
• Constraints on the ultracompact minihalos using neutrino signals from the gravitino dark matter decay

Cited by in corpus (23)

• The First Three Seconds: a Review of Possible Expansion Histories of the Early Universe
• Revisiting constraints on small scale perturbations from big-bang nucleosynthesis
• Density profiles of ultracompact minihalos: Implications for constraining the primordial power spectrum
• Are ultracompact minihalos really ultracompact?
• Influence of large local and non-local bispectra on primordial black hole abundance
• 3D simulations with boosted primordial power spectra and ultracompact minihalos
• Modeling dark matter subhalos in a constrained galaxy: Global mass and boosted annihilation profiles
• Predicting the density profiles of the first halos
• Constraining first-order phase transitions with curvature perturbations
• Ultracompact minihalos as probes of inflationary cosmology
• Constraints on small-scale primordial power by annihilation signals from extragalactic dark matter minihalos
• Beyond subhalos: Probing the collective effect of the Universe's small-scale structure with gravitational lensing
• Milky Way Accelerometry via Millisecond Pulsar Timing
• Primordial black holes and curvature perturbations from false vacuum islands
• Constraints on holographic QCD phase transitions from PTA observations
• Constraints on primordial black holes and curvature perturbations from the global 21cm signal
• Astrophysical Observations of a Dark Matter-Baryon Fifth Force
• A new bound on the low reheating temperature with dark matter
• Constraints on the small scale curvature perturbation using Planck-2015 data
• Heating of galactic gas by dark matter annihilation in ultracompact minihalos
• Tau neutrinos from ultracompact dark matter minihalos and constraints on the primordial curvature perturbations
• Influence of the deviation of the matter power spectrum at small scales on the global 21-cm signal at cosmic dawn
• Hunting Dark Matter in ultra-compact structures within the Milky-Way