Population synthesis of pulsar wind nebulae and pulsar halos in the Milky Way -- Predicted contributions to the very-high-energy sky

Abstract

The discovery of extended gamma-ray emission toward a number of middle-aged pulsars suggests the possibility of long-lived particle confinement beyond the classical pulsar wind nebula (PWN) stage. How this emerging source class can be extrapolated to a Galactic population remains unclear. We aim to evaluate how pulsar halos fit in existing TeV observations, under the assumption that all middle-aged pulsars develop halos similar to those observed toward the J0633+1746 or B0656+14 pulsars. We modeled the populations of supernova remnants, PWNe, and pulsar halos in the Milky Way. The PWN-halo evolutionary sequence is described in a simple yet coherent framework, and both kinds of objects are assumed to share the same particle injection properties. We then assessed the contribution of the different source classes to the very-high-energy emission from the Galaxy. The synthetic population can be made consistent with the flux distribution of all known objects, including unidentified objects, for a reasonable set of parameters. The fraction of the populations predicted to be detectable in surveys of the Galactic plane with HESS. and HAWC is then found to be in good agreement with their actual outcome, with a number of detectable halos ranging from 30 to 80% of the number of detectable PWNe. Prospects for CTA involve the detection of 250-300 sources in the Galactic Plane Survey, including 170 PWNe and up to 100 halos. The extent of diffusion suppression in halos has a limited impact on such prospects but its magnitude has a strong influence. The level of diffuse emission from unresolved populations in each survey is found to be dominated by halos and comparable to large-scale interstellar radiation powered by cosmic rays above 0.1-1TeV. Pulsar halos are shown to be viable counterparts to a fraction of the currently unidentified sources if they develop around most middle-aged pulsars (abridged).

16 pages, 22 figures, accepted for publication in A&A

References in corpus (30)

• The NumPy array: a structure for efficient numerical computation
• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• The Parkes multibeam pulsar survey: VI. Discovery and timing of 142 pulsars and a Galactic population analysis
• Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth
• Milagro Observations of Multi-TeV Emission from Galactic Sources in the Fermi Bright Source List
• 3HWC: The Third HAWC Catalog of Very-High-Energy Gamma-ray Sources
• The observed velocity distribution of young pulsars
• A radiation transfer model for the Milky-Way: I. Radiation fields and application to High Energy Astrophysics
• Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622 + 3749 Observed by LHAASO-KM2A
• Galactic factories of cosmic-ray electrons and positrons
• Gamma-ray halos around pulsars as the key to understanding cosmic ray transport in the Galaxy
• Cosmic-Ray Propagation in Light of Recent Observation of Geminga
• Contribution of pulsars to cosmic-ray positrons in light of recent observation of inverse-Compton halos
• Evidences of low-diffusion bubbles around Galactic pulsars
• Timing of young radio pulsars II. Braking indices and their interpretation
• Evolutionary Models for 43 Galactic Supernova Remnants with Distances and X-ray Spectra
• Self-Generated Cosmic-Ray Turbulence Can Explain the Morphology of TeV Halos
• On the potential of bright, young pulsars to power ultra-high gamma-ray sources
• Energy dependent morphology of the pulsar wind nebula HESS J1825-137 with Fermi-LAT
• Evidence that Ultra-High-Energy Gamma Rays are a Universal Feature Near Powerful Pulsars
• Energetics and Birth Rates of Supernova Remnants in the Large Magellanic Cloud
• Evidence of TeV Halos Around Millisecond Pulsars
• Modelling the Galactic very-high-energy $\gamma$-ray source population
• The Galactic population and properties of young, highly-energetic pulsars
• A pulsar wind nebula origin of the LHAASO-detected UHE gamma-ray sources
• Modeling the γ-ray Pulsar Wind Nebulae population in our Galaxy
• Deciphering Residual Emissions: Time-Dependent Models for the Non-Thermal Interstellar Radiation from the Milky Way
• The contribution of Galactic TeV pulsar wind nebulae to Fermi-LAT diffuse emission
• Morphology of Gamma-Ray Halos around Middle-Aged Pulsars: Influence of the Pulsar Proper Motion
• Survey of the Galactic Plane with the CherenkovTelescope Array

Cited by in corpus (18)

• Insights from LHAASO and IceCube into the origin of the Galactic diffuse TeV--PeV emission
• Where are Milky Way's Hadronic PeVatrons?
• Are pulsar halos rare ?
• From young to old: the evolutionary path of Pulsar Wind Nebulae
• Diffuse Ultra-High-Energy Gamma-Ray Emission From TeV Halos
• Pulsars Do Not Produce Sharp Features in the Cosmic-Ray Electron and Positron Spectra
• Sensitivity of the Cherenkov Telescope Array to TeV photon emission from the Large Magellanic Cloud
• Prospects for a survey of the Galactic plane with the Cherenkov Telescope Array
• Gamma-ray halos around pulsars: impact on pulsar wind physics and galactic cosmic ray transport
• TRAPUM search for pulsars in supernova remnants and pulsar wind nebulae -- I. Survey description and initial discoveries
• On the Contribution of Unresolved Pulsars to the Ultra-high-energy Galactic Diffuse Gamma-Ray Emission
• The Origin of the Very-High-Energy Diffuse $\gamma$-Ray Emission: The Case for Galactic Source Cocoons
• Mirages and Large TeV Halo-Pulsar Offsets from Cosmic Ray Propagation
• Detecting and characterizing pulsar haloes with the Cherenkov Telescope Array
• Could the TeV emission of starburst galaxies originate from pulsar wind nebulae?
• Pulsar+escape: the recipe for LHAASO sources ?
• New estimate for the contribution of the Geminga pulsar to the positron excess
• Investigating the emission signatures of pulsar halo candidate HESS J1813-126