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Multi-TeV Emission From the Vela Pulsar.
Alice K Harding1, Constantinos Kalapotharakos1,2, Monica Barnard3
1Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771.
The Astrophysical Journal. Letters
|June 20, 2019
Summary
The Vela pulsar emits high-energy radiation up to 30 TeV. A new model explains its broad-band spectrum from infrared to very-high energies, matching observations and predicting future emissions.
Area of Science:
- * Astrophysics
- * High-Energy Astronomy
- * Pulsar Physics
Background:
- * The H.E.S.S. II telescope detected pulsed emission from the Vela pulsar above 3 TeV.
- * Pulsar magnetosphere simulations suggest particle acceleration in the equatorial current sheet.
- * Understanding broad-band emission from pulsars is crucial for high-energy astrophysics.
Purpose of the Study:
- * To develop a model for the Vela pulsar's broad-band spectrum from infrared to beyond 10 TeV.
- * To explain the observed infrared-optical, GeV, and multi-TeV emissions.
- * To investigate particle acceleration mechanisms within the pulsar magnetosphere.
Main Methods:
- * Modeled broad-band spectrum using particle acceleration in the equatorial current sheet and polar cap cascades.
- * Calculated synchrotron emission from electron-positron pairs for IR-optical radiation.
- * Modeled curvature radiation for Fermi GeV emission and inverse-Compton scattering for very-high-energy emission.
Main Results:
- * The model successfully accounts for observed infrared-optical emission via synchrotron radiation.
- * Curvature radiation in the current sheet produces GeV emission from particles with 30-60 TeV.
- * Inverse-Compton scattering of IR-optical photons explains very-high-energy emission up to 30 TeV.
Conclusions:
- * The proposed model successfully reproduces the Vela pulsar's observed broad-band spectrum.
- * Particle acceleration in the current sheet and polar cap cascades are key to Vela's emission.
- * The model provides predictions for multi-TeV emission, guiding future observations.
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