The Physics of Pulsar Halos: Research Progress and Prospect

Abstract

Diffusive TeV gamma-ray emissions have been recently discovered extending beyond the pulsar wind nebulae of a few middle-aged pulsars, implying that energetic electron/positron pairs are escaping from the pulsar wind nebulae and radiating in the ambient interstellar medium. It has been suggested that these extended emissions constitute a distinct class of nonthermal sources, termed "pulsar halos". In this article, I will review the research progress on pulsar halos and discuss our current understanding on their physics, including the multiwavelength observations, different theoretical models, as well as implications for the origin of cosmic-ray positron excess and Galactic diffuse gamma-ray emission.

26 pages, 5 figures, 2 tables; invited review for International Journal of Modern Physics A

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Cited by in corpus (18)

• HAWC Detection of a TeV Halo Candidate Surrounding a Radio-quiet pulsar
• Pulsars Do Not Produce Sharp Features in the Cosmic-Ray Electron and Positron Spectra
• Ultra-High-Energy Gamma-Ray Astronomy
• Geminga's pulsar halo: an X-ray view
• Gamma-ray halos around pulsars: impact on pulsar wind physics and galactic cosmic ray transport
• Revisiting the Chandra Observation on the Region of PSR J1809-1917: Indication of an X-ray Halo and Implication for the Origin of HESS J1809-193
• Effect of magnetic field correlation length on the gamma-ray pulsar halo morphology under anisotropic diffusion
• Dissecting the emission from LHAASO J0341+5258: implications for future multi-wavelength observations
• Constraining the slow-diffusion zone size and electron injection spectral index for the Geminga pulsar halo
• Constraints on the $e^{\pm }$ Pair Injection of Pulsar Halos: Implications from the Galactic Diffuse Multi-TeV Gamma-ray Emission
• Mirages and Large TeV Halo-Pulsar Offsets from Cosmic Ray Propagation
• Anisotropic Diffusion of $e^{\pm }$ in Pulsar Halos over Multiple Coherence of Magnetic Fields
• PHECT: A lightweight computation tool for pulsar halo emission
• Discrete treatment of inverse Compton scattering: implications on parameter estimation in gamma-ray astronomy
• Diagnosing Interstellar Magnetic Turbulence with TeV Pulsar Halos
• Investigating the emission signatures of pulsar halo candidate HESS J1813-126
• Anisotropic Diffusion in Pulsar Halos: Interpreting the asymmetric morphology of Geminga and Monogem halos measured by HAWC
• Search for TeV emission from spider millisecond pulsars with HAWC