English
Related papers

Related papers: Gamma-ray Pulsars in a Modified Polar Cap Scenario

200 papers

We examine the potential for gamma-ray conversion to electron-positron pairs, either in the field of a nucleus or of an electron of a detector, to measure the fraction P of linear polarization of cosmic gamma sources. For this purpose we…

Instrumentation and Methods for Astrophysics · Physics 2013-09-27 Denis Bernard

The POLAR detector is a space based Gamma-Ray Burst (GRB) polarimeter sensitive in the 15-500 keV energy range. Apart from its main scientific goal as a Gamma-Ray Burst polarimeter it is also able to detect photons from pulsars in orbit. By…

The study of physical processes associated with particle acceleration in the open field line region above the polar cap (PC) of an isolated neutron star (NS) plays a fundamental role in our understanding and interpretation of high-energy…

Astrophysics · Physics 2007-05-23 Alice K. Harding , Alexander G. Muslimov

Little attention has so far been paid to the division of the observed population between pulsars of the two spin directions that are possible. Almost all pulsars with positive corotational charge density at the polar caps are expected to…

High Energy Astrophysical Phenomena · Physics 2015-06-04 P. B. Jones

The gamma-ray emitting binary stellar system LS I +61 303 was observed with the Imaging X-ray Polarimetry Explorer (IXPE) on two successive orbits over orbital phases of 0.74 to 1.05. Polarization is detected at a significance of…

High Energy Astrophysical Phenomena · Physics 2026-05-18 Philip Kaaret , Sudip Chakraborty , Daniel Golonka , Oliver J. Roberts , Ioannis Liodakis , Andrea Gnarini , Steven R. Ehlert , Joel B. Coley

In the canonical model of a pulsar, rotational energy is transmitted through the surrounding plasma via two electrical circuits, each connecting to the star over a small region known as a "polar cap." For a dipole-magnetized star, the polar…

High Energy Astrophysical Phenomena · Physics 2018-01-03 Samuel E. Gralla , Alexandru Lupsasca , Alexander Philippov

XL-Calibur is a balloon-borne Compton polarimeter for X-rays in the $\sim$15-80 keV range. Using an X-ray mirror with a 12 m focal length for collecting photons onto a beryllium scattering rod surrounded by CZT detectors, a…

The extended X-ray emission observed in the direction of several molecular clouds in the central molecular zone of our Galaxy exhibits spectral and temporal properties consistent with the X-ray echo scenario. This concept postulates that…

High Energy Astrophysical Phenomena · Physics 2026-03-25 Ildar Khabibullin , Eugene Churazov , Riccardo Ferrazzoli , Philip Kaaret , Jeffery J. Kolodziejczak , Frédéric Marin , Rashid Sunyaev , Jiri Svoboda , Alexey Vikhlinin , Thibault Barnouin , Chien-Ting Chen , Enrico Costa , Laura Di Gesu , Alessandro Di Marco , Steven R. Ehlert , William Forman , Dawoon E. Kim , Ralph Kraft , W. Peter Maksym , Giorgio Matt , Juri Poutanen , Paolo Soffitta , Douglas A. Swartz , Ivan Agudo , Lucio Angelo Antonelli , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolo Bucciantini , Fiamma Capitanio , Simone Castellano , Elisabetta Cavazzuti , Stefano Ciprini , Alessandra De Rosa , Ettore Del Monte , Niccolò Di Lalla , Immacolata Donnarumma , Victor Doroshenko , Michal Dovciak , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Jeremy Heyl , Wataru Iwakiri , Svetlana G. Jorstad , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Henric Krawczynski , Fabio La Monaca , Luca Latronico , Ioannis Liodakis , Simone Maldera , Alberto Manfreda , Alan P. Marscher , Herman L. Marshall , Francesco Massaro , Ikuyuki Mitsuishi , Tsunefumi Mizuno , Fabio Muleri , Michela Negro , Chi-Yung Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel Lawrence Peirson , Melissa Pesce-Rollins , Pierre-Olivier Petrucci , Maura Pilia , Andrea Possenti , Simonetta Puccetti , Brian D. Ramsey , John Rankin , Ajay Ratheesh , Oliver J. Roberts , Roger W. Romani , Carmelo Sgro , Patrick Slane , Gloria Spandre , Toru Tamagawa , Fabrizio Tavecchio , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Francesco Tombesi , Alessio Trois , Sergey S. Tsygankov , Roberto Turolla , Jacco Vink , Martin C. Weisskopf , Kinwah Wu , Fei Xie , Silvia Zane

The observations of gamma-ray emission from pulsars with the Fermi-LAT detector and the detection of the Crab pulsar with the VERITAS array of Cherenkov telescopes at energies above 100 GeV make it unlikely that curvature radiation is the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Maxim Lyutikov , Nepomuk Otte , Andrew McCann

The model of pulsar radio emission is discussed in which a coherent radio emis-sion is excited in a vacuum gap above polar cap of neutron star. Pulsar X and gamma radiation are considered as the result of low-frequency radio emission…

Astrophysics · Physics 2009-06-23 V. M. Kontorovich , A. B. Flanchik

The Fermi LAT discovery that classical novae produce >100 MeV gamma-rays establishes that shocks and relativistic particle acceleration are key features of these events. These shocks are likely to be radiative due to the high densities of…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Brian D. Metzger , Thomas Finzell , Indrek Vurm , Romain Hascoet , Andrei M. Beloborodov , Laura Chomiuk

Recent observations of the polarisation of the optical pulses from the Crab pulsar motivated detailed comparative studies of the emission predicted by the polar cap, the outer gap and the two-pole caustics models. In this work, we study the…

Astrophysics · Physics 2008-11-26 J. Petri , J. Kirk

Gamma-ray emission from pulsars is thought to arise from accelerating regions in pulsar's outer magnetosphere. The shape of the light curves is thus sensitive to the details of the magnetic geometry of the magnetosphere. In this work, we…

High Energy Astrophysical Phenomena · Physics 2009-11-03 Xue-Ning Bai , Anatoly Spitkovsky

Synchrotron radiation is widely considered as the origin of the pulsed non-thermal emissions from rotation-powered pulsars in optical and X-ray bands. In this paper, we study the synchrotron radiation emitted by the created electron and…

High Energy Astrophysical Phenomena · Physics 2017-03-15 Shota Kisaka , Shuta J. Tanaka

While the scientific potential of high-energy X-ray and gamma-ray polarimetry has long been recognized, measuring the polarization of high-energy photons is challenging. To date, there has been very few significant detections from an…

Instrumentation and Methods for Astrophysics · Physics 2023-04-05 Denis Bernard , Tanmoy Chattopadhyay , Fabian Kislat , Nicolas Produit

We show that the $\gamma$-ray pulsar observables, i.e., their total $\gamma$-ray luminosity, $L_{\gamma}$, spectral cut-off energy, $\epsilon_{\rm cut}$, stellar surface magnetic field, $B_{\star}$, and spin-down power $\dot{\mathcal{E}}$,…

High Energy Astrophysical Phenomena · Physics 2019-09-25 Constantinos Kalapotharakos , Alice K. Harding , Demosthenes Kazanas , Zorawar Wadiasingh

The empirical relation between the X-ray luminosity (in the 2-10 keV band) and the rate of spin-down energy loss of a sample of 37 pulsars is re-examined considering recent data from ASCA, RXTE, BeppoSAX, Chandra, and XMM-Newton. The data…

Astrophysics · Physics 2009-11-07 Andrea Possenti , Rossella Cerutti , Monica Colpi , Sandro Mereghetti

The main possibilities of investigation of leptons and bosons birth in interaction of polarized photons are considered. The usage of $\gamma \gamma \to f \bar{f} [+\gamma]$ reactions for the luminosity measurement on linear photon collider…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Shishkina

We report on observations of the polarization of optical and {\gamma}-ray photons from the Crab nebula and pulsar system using the Galway Astronomical Stokes Polarimeter (GASP), the Hubble Space Telescope/Advanced Camera for Surveys…

High Energy Astrophysical Phenomena · Physics 2016-01-27 Paul Moran , Gillian Kyne , Christian Gouiffes , 3 , Philipe Laurent , Gregg Hallinan , Michael Redfern , Andrew Shearer

Binary pulsar systems emit potentially detectable components of gamma ray emission due to Comptonization of the optical radiation of the companion star by relativistic electrons of the pulsar wind, both before and after termination of the…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Dmitry Khangulyan , Felix Aharonian , Sergey Bogovalov , Marc Ribó