Isotropic X-ray bound on Primordial Black Hole Dark Matter

Abstract

We revisit the constraints on evaporating primordial black holes (PBHs) from the isotropic X-ray and soft gamma-ray background in the mass range $10^{16}-10^{18}$ g. We find that they are stronger than usually inferred due to two neglected effects: i) The contribution of the annihilation radiation due to positrons emitted in the evaporation process. ii) The high-latitude, Galactic contribution to the measured isotropic flux. We study the dependence of the bounds from the datasets used, the positron annihilation conditions, and the inclusion of the astrophysical background. We push the exclusion limit for non-spinning PBH with monochromatic mass function as the totality of dark matter to 1.5$\times 10^{17}$g, which represents a $\sim$15$\%$ improvement with respect to earlier bounds and translates into almost an order of magnitude improvement in the PBH fraction in the already probed region. We also show that the inclusion of spin and/or an extended, log-normal mass function lead to tighter bounds. Our study suggests that the isotropic flux is an extremely promising target for future missions in improving the sensitivity to PBHs as candidates for dark matter.

arXiv comment10 pages, 14 figures Clarification added and a software output interpretation mistake corrected; only minor changes to the results

References in corpus (33)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• A Universal Density Profile from Hierarchical Clustering
• The Burst Alert Telescope (BAT) on the Swift MIDEX Mission
• Did LIGO detect dark matter?
• SparsePak: A Formatted Fiber Field Unit for The WIYN Telescope Bench Spectrograph. I. Design, Construction, and Calibration
• Primordial Black Hole Scenario for the Gravitational-Wave Event GW150914
• Primordial Black Holes as Dark Matter: Recent Developments
• Toward the Standard Population Synthesis Model of the X-Ray Background: Evolution of X-Ray Luminosity and Absorption Functions of Active Galactic Nuclei Including Compton-Thick Populations
• Primordial black hole constraints for extended mass functions
• The Spectrum of Diffuse Cosmic Hard X-Rays Measured with HEAO-1
• Cosmological black hole spin evolution by mergers and accretion
• The 511 keV emission from positron annihilation in the Galaxy
• Primordial black holes as a dark matter candidate are severely constrained by the Galactic Center 511 keV gamma-ray line
• INTEGRAL constraints on primordial black holes and particle dark matter
• Cosmological constraints on exotic injection of electromagnetic energy
• Cosmic X-ray background and Earth albedo Spectra with Swift/BAT
• Voyager 1 $e^{\pm }$ Further Constrain Primordial Black Holes as Dark Matter
• INTEGRAL observations of the cosmic X-ray background in the 5-100 keV range via occultation by the Earth
• Microlensing and dynamical constraints on primordial black hole dark matter with an extended mass function
• Neutrino and Positron Constraints on Spinning Primordial Black Hole Dark Matter
• BlackHawk v2.0: A public code for calculating the Hawking evaporation spectra of any black hole distribution
• Constraining primordial black hole abundance with the Galactic 511 keV line
• The Initial Spin Probability Distribution of Primordial Black Holes
• Constraints on primordial black holes from Galactic gamma-ray background
• Direct Detection of Hawking Radiation from Asteroid-Mass Primordial Black Holes
• Planck Constraint on Relic Primordial Black Holes
• The spectrum of the cosmic X-ray background observed by RTXE/PCA
• The power spectrum on small scales: Robust constraints and comparing PBH methodologies
• The lives and deaths of positrons in the interstellar medium
• Exotic energy injection with ExoCLASS: Application to the Higgs portal model and evaporating black holes
• X-ray and gamma-ray limits on the primordial black hole abundance from Hawking radiation
• The Birth and Growth of Neutralino Haloes
• A robust estimate of the Milky Way mass from rotation curve data

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• A brief review on primordial black holes as dark matter
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• Strong constraints on primordial black hole dark matter from 16 years of INTEGRAL/SPI observations
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• The Positron Puzzle
• Updated Constraints on Primordial Black Hole Evaporation
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• Primordial Black Hole Dark Matter evaporating on the Neutrino Floor
• Electron scattering of light new particles from evaporating primordial black holes
• Reticulum II: Particle Dark Matter and Primordial Black Holes Limits
• Revisiting the constraints on primordial black hole abundance with the isotropic gamma ray background
• Primordial Black Hole Dark Matter in the Context of Extra Dimensions
• X-Ray Constraints on Dark Photon Tridents
• Future Constraints on Primordial Black Holes from XGIS-THESEUS
• Searching for Signal of Primordial Black Hole from CMB Lensing and $\gamma$-ray Emissions
• Search for primordial black hole dark matter with X-ray spectroscopic and imaging satellite experiments and prospects for future satellite missions
• Hunting Primordial Black Hole Dark Matter in Lyman-$\alpha$ Forest
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• Constraints on primordial black holes from interstellar dust temperature in the Galaxy
• Strong Constraints on Dark Photon and Scalar Dark Matter Decay from INTEGRAL and AMS-02 data
• Tidal effects on primordial black hole capture in neutron stars
• Fermionic sub-GeV Dark Matter from evaporating Primordial Black Holes at DarkSide-50
• Physics Beyond the Standard Model with BlackHawk v2.0
• Constraining primordial black hole abundance with Insight-HXMT
• The Dark Dimension, the Swampland, and the Dark Matter Fraction Composed of Primordial Black Holes
• Limits on primordial black holes detectability with Isatis: A BlackHawk tool
• Sensitivities on non-spinning and spinning primordial black hole dark matter with global 21 cm troughs