HIGH-ENERGY EMISSION FROM PULSAR MAGNETOSPHERES

2006 ◽  
Vol 21 (17) ◽  
pp. 1319-1337 ◽  
Author(s):  
KOUICHI HIROTANI
Keyword(s):  
Neutron Star ◽  
Gamma Ray ◽  
Potential Drop ◽  
High Energy ◽  
Particle Accelerators ◽  
Two Dimensional ◽  
Essential Information ◽  
Field Lines ◽  
Gap Models ◽  
Star Surface

A synthesis of the present knowledge on gamma-ray emission from the magnetosphere of a rapidly rotating neutron star is presented, focusing on the electrodynamics of particle accelerators. The combined curvature, synchrotron, and inverse-Compton emission from ultra-relativistic positrons and electrons, which are created by two-photon and/or one-photon pair creation processes, or emitted from the neutron-star surface, provide us with essential information on the properties of the accelerator — electric potential drop along the magnetic field lines. A new accelerator model, which is a mixture of traditional inner gap and outer gap models, is also proposed, by solving the Poisson equation for the electrostatic potential together with the Boltzmann equations for particles and gamma-rays in the two-dimensional configuration and two-dimensional momentum spaces.

scholarly journals Double Neutron Star Mergers and Short Gamma-ray Bursts: Long-lasting High-energy Signatures and Remnant Dichotomy

2018 ◽  
Vol 854 (1) ◽  
pp. 60 ◽  
Author(s):  
Kohta Murase ◽  
Michael W. Toomey ◽  
Ke Fang ◽  
Foteini Oikonomou ◽  
Shigeo S. Kimura ◽  
...  
Keyword(s):  
Neutron Star ◽  
Gamma Ray ◽  
High Energy ◽  
Gamma Ray Bursts

scholarly journals Radiation Beaming in Pulsars

1971 ◽  
Vol 46 ◽  
pp. 455-456
Author(s):  
V. Canuto
Keyword(s):  
Magnetic Field ◽  
Neutron Star ◽  
Coming Out ◽  
Critical Magnetic Field ◽  
Zero Field ◽  
Ordinary Wave ◽  
Magnetic Field Axis ◽  
Field Lines ◽  
Star Surface ◽  
The Magnetic Field

It is usually considered that the beaming of the radiation coming out of a pulsar has to be strictly connected with the mechanism producing the radiation itself. We want to show that even when the emitting mechanism gives rise to an isotropically distributed radiation, the presence of a strong magnetic field will automatically beam the radiation preferentially along the magnetic field line rather than in any other direction. We have computed the Compton scattering and from that the opacity KH (K0 is the opacity for zero field). In Figure 1 the ratio KH/K0 is given vs. θ, the angle between the propagation vector and the magnetic field axis. Hq is a critical magnetic field numerically equal to 4.41 × 1013 G; Ne is the electron density. For the ordinary wave the opacity is reduced at θ = 0, while it is unaffected at θ = π/2 where KH → K0. Even at θ = π/4 the ratio KH/K0 is still ≃ 10−2, and a good beaming is still present. The values of the parameters are proper for a neutron star surface. It is to be noticed that the ratio KH/K0 is of the order of (ω/ωH)2 or [(kT/mc2)/(H/Hq]2. One therefore can conclude that the presence of a magnetic field itself assures the beaming of radiation along the field lines.

scholarly journals Magnetic fractures or reconnection of type II

2010 ◽  
Vol 6 (S274) ◽  
pp. 56-61
Author(s):  
Gerhard Haerendel
Keyword(s):  
Particle Production ◽  
Gamma Ray ◽  
Magnetic Energy ◽  
High Energy ◽  
Compact Objects ◽  
High Energy Particle ◽  
Shear Stresses ◽  
Low Density ◽  
Field Lines ◽  
Auroral Arcs

AbstractThe importance of reconnection in astrophysics has been widely recognized. It is instrumental in storing and releasing magnetic energy, the latter often in a dramatic fashion. A closely related process, playing in very low beta plasmas, is much less known. It is behind the acceleration of auroral particles in the low-density environment several 1000 km above the Earth. It involves the appearance of field-parallel voltages in presence of intense field-aligned currents. The underlying physical process is the release of magnetic shear stresses and conversion of the liberated magnetic energy into kinetic energy of the particles creating auroral arcs. In this process, field lines disconnect from the field anchored in the ionosphere and reconnect to other field lines. Because of the stiffness of the magnetic field, the process resembles mechanical fractures. It is typically active in the low-density magnetosphere of planets. However, it can also lead to significant energy conversion with high-energy particle production and subsequent gamma ray emissions in stellar magnetic fields, in particular of compact objects.

The cosmic matrix in the 50th anniversary of relativistic astrophysics

2017 ◽  
Vol 26 (10) ◽  
pp. 1730019
Author(s):  
R. Ruffini ◽  
Y. Aimuratov ◽  
L. Becerra ◽  
C. L. Bianco ◽  
M. Karlica ◽  
...  
Keyword(s):  
Neutron Star ◽  
Gamma Ray ◽  
50Th Anniversary ◽  
High Energy ◽  
Relativistic Astrophysics ◽  
Ultra High Energy ◽  
High Energy Cosmic Rays ◽  
S Matrix ◽  
The Universe ◽  
Advance Knowledge

Our concept of induced gravitational collapse (IGC paradigm) starting from a supernova occurring with a companion neutron star, has unlocked the understanding of seven different families of gamma ray bursts (GRBs), indicating a path for the formation of black holes in the universe. An authentic laboratory of relativistic astrophysics has been unveiled in which new paradigms have been introduced in order to advance knowledge of the most energetic, distant and complex systems in our universe. A novel cosmic matrix paradigm has been introduced at a relativistic cosmic level, which parallels the concept of an S-matrix introduced by Feynmann, Wheeler and Heisenberg in the quantum world of microphysics. Here the “in” states are represented by a neutron star and a supernova, while the “out” states, generated within less than a second, are a new neutron star and a black hole. This novel field of research needs very powerful technological observations in all wavelengths ranging from radio through optical, X-ray and gamma ray radiation all the way up to ultra-high-energy cosmic rays.

scholarly journals JD6 - The Connection between Radio Properties and High Energy Emission in AGNs

2012 ◽  
Vol 10 (H16) ◽  
pp. 187-198
Author(s):  
Gabriele Giovannini ◽  
Teddy Cheung
Keyword(s):  
Gamma Ray ◽  
Galactic Nuclei ◽  
High Energy ◽  
Jet Physics ◽  
Spectral Energy ◽  
Essential Information ◽  
Multi Wavelength ◽  
Radio Band ◽  
High Energy Emission ◽  
Wavelength Monitoring

AbstractWhile observations in the radio band are providing essential information on the innermost structures of relativistic jets in active galactic nuclei (AGN), the recent detection byFermiof gamma-ray emission from many hundreds of blazars shows that the maximum jet power is emitted at high energies. Multi-wavelength monitoring observations further allow variability studies of the AGN spectral energy distributions over 13 orders of magnitude in frequency. The Joint Discussion offered the possibility for a comprehensive discussion of advances in the observational domain and stimulated theoretical discussion about our current understanding of jet physics.

scholarly journals A model for high-energy emission of the Intrabinary shock in pulsar binaries

2018 ◽  
Vol 168 ◽  
pp. 04013
Author(s):  
Hongjun An
Keyword(s):  
Neutron Star ◽  
Inclination Angle ◽  
Binary Systems ◽  
Gamma Ray ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Spectral Energy ◽  
Plasma Properties ◽  
Energy Emission ◽  
High Energy Emission

We present our studies of intrabinary shock emission for astrophysical binary systems with a neutron star. We construct a model for the shock emission and compare the model calculation with the light curve and the spectral energy distribution of the gamma-ray binary 1FGL J1018.6-5856. The model assumes a slow and a fast population of particles accelerated in the shock, and computes the high-energy emission spectra and orbital light curves produced by synchrotron, self-Compton and external Compton processes of the high-energy particles in the shock. The model allows one to study plasma properties and to constrain the binary geometry, most importantly the inclination angle (i). We discuss potential use of this model for other pulsar binaries to determine the inclination angle of the binary hence the mass of the neutron star.

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