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Related papers: Constraining Pulsar Magnetosphere Geometry with Ga…

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Current models of pulsar gamma-ray emission use the magnetic field of a rotating dipole in vacuum as a first approximation to the shape of plasma-filled pulsar magnetosphere. In this paper we revisit the question of gamma-ray light-curve…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Xue-Ning Bai , Anatoly Spitkovsky

We modelled the radio and gamma-ray light curves of millisecond pulsars using outer gap, two-pole caustic, low-altitude slot gap, and pair-starved polar cap geometric models, combined with a semi-empirical conal radio model. We find that no…

High Energy Astrophysical Phenomena · Physics 2014-11-04 C Venter , TJ Johnson , AK Harding , JE Grove

The light curves of gamma-ray pulsars detected by the Fermi Large Area Telescope show great variety in profile shape and position relative to their radio profiles. Such diversity hints at distinct underlying magnetospheric and/or emission…

High Energy Astrophysical Phenomena · Physics 2014-11-10 M. Breed , C. Venter , A. K. Harding , T. J. Johnson

The Fermi Large Area Telescope (LAT) has recently reported the detection of pulsed gamma-rays from 6 young pulsars (J0631+1036, J0659+1414, J0742-2822, J1420-6048, J1509-5850, and J1718-3825), all exhibiting single-peaked pulse profiles…

High Energy Astrophysical Phenomena · Physics 2011-05-23 A. S. Seyffert , C. Venter , O. C. de Jager , A. K. Harding

We develop kinetic plasma models of pulsar magnetospheres with magnetic-field-line-dependent plasma injection that reveal the importance of various magnetosphere regions in regulating the gamma-ray emission. We set different particle…

High Energy Astrophysical Phenomena · Physics 2023-07-28 Constantinos Kalapotharakos , Zorawar Wadiasingh , Alice K. Harding , Demosthenes Kazanas

We explore a non-stationary outer gap scenario for gamma-ray emission process in pulsar magnetosphere. Electrons/positrons that migrate along the magnetic field line and enter the outer gap from the outer/inner boundaries activate the…

High Energy Astrophysical Phenomena · Physics 2015-12-16 J. Takata , C. W. Ng , K. S. Cheng

The light curves and spectral properties of more than 200 $\gamma$-ray pulsars have been measured in unsurpassed detail in the eight years since the launch of the hugely successful Fermi Large Area Telescope (LAT) $\gamma$-ray mission. We…

High Energy Astrophysical Phenomena · Physics 2017-02-20 Monica Barnard , Christo Venter , Alice K. Harding

We have simulated a population of young spin-powered pulsars and computed the beaming pattern and lightcurves for the three main geometrical models: polar cap emission, two-pole caustic ("slot gap") emission and outer magnetosphere…

Astrophysics · Physics 2011-02-11 Kyle P. Watters , Roger W. Romani , Patrick Weltevrede , Simon Johnston

Since its launch in 2008, the Fermi Large Area Telescope (LAT) has detected over 200 -ray pulsars above 100 MeV. This population of pulsars is characterised by a rich diversity of light curve morphologies. Researchers have been using both…

High Energy Astrophysical Phenomena · Physics 2017-12-25 M. C. Bezuidenhout , C. Venter , A. S. Seyffert , A. K. Harding

We previously obtained constraints on the viewing geometries of 6 Fermi LAT pulsars using a multiwavelength approach (Seyffert et al., 2011). To obtain these constraints we compared the observed radio and $\gamma$-ray light curves (LCs) for…

High Energy Astrophysical Phenomena · Physics 2015-01-28 A. S. Seyffert , C. Venter , T. J. Johnson , A. K. Harding

Since the launch of the Large Area Telescope (LAT) on board the Fermi spacecraft in June 2008, the number of observed gamma-ray pulsars has increased dramatically. A large number of these are also observed at radio frequencies. Constraints…

High Energy Astrophysical Phenomena · Physics 2012-01-24 A. S. Seyffert , C. Venter , T. J. Johnson , A. K. Harding

We study the gamma-ray emission patterns and light curves in dissipative pulsar magnetospheres. We produce the gamma-ray light curves by using the geometric method and the particle trajectory method. For the geometric method, assuming the…

High Energy Astrophysical Phenomena · Physics 2019-04-10 Gang Cao , Xiongbang Yang

(Abridged) Gamma-ray emission from pulsars has long been modeled using a vacuum dipole field. This approximation ignores changes in the field structure caused by the magnetospheric plasma and strong plasma currents. We present the first…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Xue-Ning Bai , Anatoly Spitkovsky

Pulsars are among the prime targets for the Large Area Telescope (LAT) aboard the recently launched Fermi observatory. The LAT will study the gamma-ray Universe between 20 MeV and 300 GeV with unprecedented detail. Increasing numbers of…

We report the detection of pulsed gamma-rays for PSRs J0631+1036, J0659+1414, J0742-2822, J1420-6048, J1509-5850 and J1718-3825 using the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (formerly known as GLAST).…

Solar and Stellar Astrophysics · Physics 2010-01-06 The Fermi LAT collaboration , the Fermi Pulsar Timing Consortium

The pulsar light curves and energy spectra are explored in dissipative pulsar magnetospheres with the Aristotelian electrodynamics (AE), where particle acceleration is fully balanced with radiation reaction. The AE magnetospheres with…

High Energy Astrophysical Phenomena · Physics 2022-02-09 Gang Cao , Xiongbang Yang

The wealth of high-energy (E > 50 MeV) and very-high-energy (E > 100 GeV) data accumulated over the past few years have provided unprecedented opportunities to probe pulsar emission models. The Fermi Large Area Telescope (LAT) has now…

High Energy Astrophysical Phenomena · Physics 2017-02-03 Christo Venter

Over the past six years, the Fermi Large Area Telescope has detected more than 150 gamma-ray pulsars, discovering a variety of light curve trends and classes. Such diversity hints at distinct underlying magnetospheric and/or emission…

High Energy Astrophysical Phenomena · Physics 2015-04-28 M. Breed , C. Venter , A. K. Harding , T. J. Johnson

The Fermi Large Area Telescope (LAT) has revolutionized high-energy (HE) astronomy, and is making enormous contributions particularly to gamma-ray pulsar science. As a result of the many new pulsar discoveries, the gamma-ray pulsar…

High Energy Astrophysical Phenomena · Physics 2011-12-15 C. Venter , T. J. Johnson , A. K. Harding

The Large Area Telescope (LAT), Fermi's main instrument, is providing a new view of the local energetic pulsar population. In addition to identifying a pulsar origin of a large fraction of the bright unidentified Galactic EGRET sources, the…

High Energy Astrophysical Phenomena · Physics 2009-12-22 G. A. Caliandro , E. C. Ferrara , D. Parent , R. W. Romani