On the contribution of the bow shock pulsar wind nebula PSR J0437-4715 to the observed fluxes of GeV-TeV positrons and antiprotons

Abstract

The orbital observatories PAMELA and AMS-02 have detected a significant excess in the cosmic ray (CR) positron flux at energies above several tens of GeV. The measured values exceed those expected in models of secondary origin of positrons due to inelastic collisions of CR nuclei with the interstellar matter. This excess may be due to the annihilation or decay of hypothetical dark matter particles or, alternatively, to the contribution of the nearest pulsars. The measured positron-to-antiproton flux ratio is virtually independent of energy from 60 to 400 GeV. This can be understood if the observed local spectra of positrons and antiprotons in the range of tens to hundreds of GeV are formed by the same source. Fast-moving pulsars form pulsar wind nebulae with bow shocks (BSPWNe), which accelerate both the positrons and electrons of the pulsar wind and the hadrons and leptons of galactic CRs from the interstellar medium via the Fermi acceleration mechanism in colliding flows. Such a system can produce identical particle spectra regardless of the site of particle injection. The nearest to the Earth millisecond pulsar PSR J0437-4715 forms a pulsar wind nebula (PWN) with a bow shock observable in optical and ultraviolet wavelengths. This BSPWN is a possible candidate for the main near-Earth ``factory'' of antiparticles along with the Geminga PWN. Considering PSR J0437-4715, we provide the Monte Carlo simulations of particle acceleration in its BSPWN and the analytical model of anisotropic diffusion in the local interstellar medium. We show that this pulsar's contribution can explain the observed positron flux from 30 GeV to 1 TeV, and simultaneously the antiproton flux at hundreds of GeV with an almost energy-independent positron-to-antiproton flux ratio using $\sim 25\%$ of the PSR J0437-4715 pulsar wind power to accelerate positrons and electrons and re-accelerate antiprotons.

arXiv commentAstronomy Letters, vol. 51, issue 8, p. 487-497 (2025)

References in corpus (37)

• Observation of an anomalous positron abundance in the cosmic radiation
• Cosmic-ray propagation and interactions in the Galaxy
• Production and propagation of cosmic-ray positrons and electrons
• Pulsars as the Sources of High Energy Cosmic Ray Positrons
• Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth
• Secondary antiprotons and propagation of cosmic rays in the Galaxy and heliosphere
• TeV Gamma Rays from Geminga and the Origin of the GeV Positron Excess
• Particle acceleration at ultrarelativistic shocks: an eigenfunction method
• Constraints on cosmic-ray propagation models from a global Bayesian analysis
• New Positron Spectral Features from Supersymmetric Dark Matter - a Way to Explain the PAMELA Data?
• Transport of Cosmic Rays in Chaotic Magnetic Fields
• GALPROP WebRun: an internet-based service for calculating galactic cosmic ray propagation and associated photon emissions
• Testing the Origin of High-Energy Cosmic Rays
• Extremely high precision VLBI astrometry of PSR J0437-4715 and implications for theories of gravity
• Heating and Non-thermal Particle Acceleration in Relativistic, Transverse Magnetosonic Shock Waves in Proton-Electron-Positron Plasmas
• Challenging cosmic ray propagation with antiprotons. Evidence for a "fresh" nuclei component?
• Pulsar wind nebulae with bow shocks: non-thermal radiation and cosmic ray leptons
• Two-zone diffusion of electrons and positrons from Geminga explains the positron anomaly
• A Survey for H$\alpha$ Pulsar Bow Shocks
• Positron flux and gamma-ray emission from Geminga pulsar and pulsar wind nebula
• Galactic factories of cosmic-ray electrons and positrons
• Contribution of pulsars to cosmic-ray positrons in light of recent observation of inverse-Compton halos
• Charting the Interstellar Magnetic Field causing the Interstellar Boundary Explorer (IBEX) Ribbon of Energetic Neutral Atoms
• Experimental entanglement redistribution under decoherence channels
• Non-linear model of particle acceleration at colliding shock flows
• GeV-TeV Cosmic Ray Leptons in the Solar System from the Bow Shock Wind Nebula of the Nearest Millisecond Pulsar J0437-4715
• The TeV Cosmic Ray Bump: a Message from Epsilon Indi or Epsilon Eridani Star?
• On the origin of observed cosmic ray spectrum below 100 TV
• First Detection of a Pulsar Bow Shock Nebula in Far-UV: PSR J0437-4715
• Particle spectra and efficiency in nonlinear relativistic shock acceleration: survey of scattering models
• Proton acceleration in colliding stellar wind binaries
• A novel prediction for secondary positrons and electrons in the Galaxy
• Nonsecondary origin of cosmic ray positrons
• Disclosing the catalog pulsars dominating the Galactic positron flux
• Examining the secondary product origin of cosmic ray positrons with the latest AMS-02 data
• Relativistic astrospheres of gamma-ray binaries: modeling of non-thermal processes
• Cosmic ray transport and acceleration in an evolving shock landscape