Gamma-Ray Emission in Dissipative Pulsar Magnetospheres: From Theory to Fermi Observations

Abstract

We compute the patterns of $\gamma$-ray emission due to curvature radiation in dissipative pulsar magnetospheres. Our ultimate goal is to construct macrophysical models that are able to reproduce the observed $\gamma$-ray light-curve phenomenology recently published in the Second Fermi Pulsar Catalog. We apply specific forms of Ohm's law on the open field lines using a broad range for the macroscopic conductivity values that result in solutions ranging, from near-vacuum to near Force-Free. Using these solutions, we generate model $\gamma$-ray light curves by calculating realistic trajectories and Lorentz factors of radiating particles, under the influence of both the accelerating electric fields and curvature radiation-reaction. We further constrain our models using the observed dependence of the phase-lags between the radio and $\gamma$-ray emission on the $\gamma$-ray peak-separation. We perform a statistical comparison of our model radio-lag vs peak-separation diagram and the one obtained for the Fermi standard pulsars. We find that for models of uniform conductivity over the entire open magnetic field line region, agreement with observations favors higher values of this parameter. We find, however, significant improvement in fitting the data with models that employ a hybrid form of conductivity; specifically, infinite conductivity interior to the light-cylinder and high but finite conductivity on the outside. In these models the $\gamma$-ray emission is produced in regions near the equatorial current sheet but modulated by the local physical properties. These models have radio-lags near the observed values and statistically best reproduce the observed light-curve phenomenology. Additionally, these models produce GeV photon cut-off energies.

Accepted for publication in ApJ (revised version, 26 pages, 23 figures)

References in corpus (12)

• The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Current Flow and Pair Creation at Low Altitude in Rotation Powered Pulsars' Force-Free Magnetospheres: Space-Charge Limited Flow
• Time-dependent pair cascades in magnetospheres of neutron stars I. Dynamics of the polar cap cascade with no particle supply from the neutron star surface
• Three-dimensional numerical simulations of the pulsar magentoshere: Preliminary results
• Time-Dependent 3D Magnetohydrodynamic Pulsar Magnetospheres: Oblique Rotators
• Fermi LAT Observations of the Vela Pulsar
• The pulsar force-free magnetosphere linked to its striped wind: time-dependent pseudo-spectral simulations
• Relativistic Force-Free Electrodynamic Simulations of Neutron Star Magnetospheres
• Modeling magnetized neutron stars using resistive MHD
• Gamma-Ray Light Curves from Pulsar Magnetospheres with Finite Conductivity
• Pulsed high energy gamma-rays from thermal populations in the current sheets of pulsar winds
• Dead zone in the polar-cap accelerator of pulsars

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