English
Related papers

Related papers: Pulsar Emission Geometry and Accelerating Field St…

200 papers

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

Pulsed emission from the Vela pulsar at energies above 3 TeV has recently been detected by the H.E.S.S. II air-Cherenkov telescope. We present a model for the broad-band spectrum of Vela from infra-red (IR) to beyond 10 TeV. Recent…

High Energy Astrophysical Phenomena · Physics 2018-12-19 Alice K. Harding , Constantinos Kalapotharakos , Monica Barnard , Christo Venter

An interesting new high-energy pulsar sub-population is emerging following early discoveries of gamma-ray millisecond pulsars (MSPs) by the Fermi Large Area Telescope (LAT). We present results from 3D emission modeling, including the…

High Energy Astrophysical Phenomena · Physics 2014-11-20 C. Venter , A. K. Harding , L. Guillemot

The vast majority of the pulsars detected by the Fermi Large Area Telescope (LAT) display spectra with exponential cutoffs falling in a narrow range around a few GeV. Early spectral modelling predicted spectral cutoff energies of up to 100…

High Energy Astrophysical Phenomena · Physics 2016-03-08 M. Breed , C. Venter , A. K. Harding

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 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…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Constantinos Kalapotharakos , Alice K. Harding , Demosthenes Kazanas

We present a summary of gamma-ray millisecond pulsar (MSP) observations with the Fermi Large Area Telescope. The radio and gamma-ray light curves of these MSPs have been modeled in the framework of the retarded vacuum dipole magnetic field.…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Tyrel J. Johnson , Christo Venter , Alice K. Harding , Lucas Guillemot

One of the main results of the Fermi Gamma-Ray Space Telescope is the discovery of {\gamma}-ray selected pulsars. The high magnetic field pulsar, PSR J0007+7303 in CTA1, was the first ever to be discovered through its {\gamma}-ray…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. A. Abdo , K. S. Wood , M. E. DeCesar , F. Gargano , F. Giordano , P. S. Ray , D. Parent , A. K. Harding , M. Coleman Miller , D. L. Wood , M. T. Wolff

Pulsed high energy radiation from pulsars is not yet completely understood. In this paper, we use the 3D self-consistent annular gap model to study light curves for both young and millisecond pulsars observed by the Fermi Gamma-ray Space…

High Energy Astrophysical Phenomena · Physics 2010-08-23 Yuan-Jie Du , G. J. Qiao , J. L. Han , K. J. Lee , R. X. Xu

Current models of gamma-ray lightcurves in pulsars suffer from large uncertainties on the precise location of particle acceleration and radiation. Here, we present an attempt to alleviate these difficulties by solving for the…

High Energy Astrophysical Phenomena · Physics 2016-02-17 Benoît Cerutti , Alexander A. Philippov , Anatoly Spitkovsky

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

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

(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

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

The vast majority of pulsars detected by the Fermi Large Area Telescope (LAT) display exponentially cutoff spectra with cutoffs falling in a narrow band around a few GeV. Early spectral modelling predicted spectral cutoffs at energies of up…

High Energy Astrophysical Phenomena · Physics 2016-07-25 M. Breed , C. Venter , A. K. Harding

$\gamma$-ray radiation from pulsars is usually thought to be mostly produced by the synchro-curvature losses of accelerated particles. Here we present a systematic study of all currently reported, good-quality Fermi-LAT pulsar spectral…

High Energy Astrophysical Phenomena · Physics 2015-07-16 Daniele Viganò , Diego F. Torres , Jonatan Martín

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

In more than four years of observation the Large Area Telescope on board the Fermi satellite has identified pulsed $\gamma$-ray emission from more than 80 young pulsars, providing light curves with high statistics. Fitting the observations…

High Energy Astrophysical Phenomena · Physics 2015-02-11 M. Pierbattista , A. K. Harding , I. A. Grenier , T. J. Johnson , P. A. Caraveo , M. Kerr , P. L. Gonthier

Context. Pulsars are detected as broadband electromagnetic emitters from the radio wavelength up to high and very high energy in the MeV/GeV and sometimes even in the TeV range. Multi-wavelength phase-resolved spectra and light curves offer…

High Energy Astrophysical Phenomena · Physics 2021-10-20 Quentin Giraud , Jérôme Pétri

The spectral characteristics of the pulsed gamma-ray emission from outer-magnetospheric particle accelerators are investigated. Either positrons or electrons are accelerated outwards by the magnetic-field-aligned electric field to emit…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Kouichi Hirotani