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Related papers: The dispersion in pulsar $\gamma$-ray efficiency

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We suggest that some observational features of high-energy radiation from pulsars should be explained in terms of three dimensional geometric models, e.g. the phase-resolved X-ray and $\gamma$-ray spectra and the energy dependent light…

Astrophysics · Physics 2009-11-10 K. S. Cheng

We report here on variable propagation effects in over twenty years of multi-frequency timing analysis of pulsar PSR B1937+21 that determine small-scale properties of the intervening plasma as it drifts through the sight line. The phase…

Astrophysics · Physics 2009-11-11 R. Ramachandran , P. Demorest , D. C. Backer , I. Cognard , A. Lommen

In this article, we revisit the gamma-ray emission observed from millisecond pulsars and globular clusters. Based on 5.6 years of data from the Fermi Gamma-Ray Space Telescope, we report gamma-ray spectra for 61 millisecond pulsars, finding…

High Energy Astrophysical Phenomena · Physics 2014-07-22 Ilias Cholis , Dan Hooper , Tim Linden

Luminosity is an intrinsic property of radio pulsars related to the properties of the magnetospheric plasma and the beam geometry, and inversely proportional to the observing frequency. In traditional models, luminosity has been considered…

Solar and Stellar Astrophysics · Physics 2013-06-11 Manjari Bagchi

Aims. We explore frequency-dependent changes in pulsar radio emission by analyzing their profile widths and emission heights, assessing whether the simple radius-to-frequency mapping (RFM) or the fan beam model can describe the data.…

High Energy Astrophysical Phenomena · Physics 2026-01-14 P. Jaroenjittichai , S. Johnston , S. Dai , M. Kerr , M. E. Lower , R. N. Manchester , L. S. Oswald , R. M. Shannon , C. Sobey , P. Weltevrede

We estimate the contribution of Galactic pulsars, both ordinary and millisecond pulsars (MSPs), to the high-energy (>100 MeV) gamma-ray background. We pay particular attention to the high-latitude part of the background that could be…

High Energy Astrophysical Phenomena · Physics 2010-01-15 C. -A. Faucher-Giguere , Abraham Loeb

We carried out observations of pulsar PSR B1919+21 at 324 MHz to study the distribution of interstellar plasma in the direction of this pulsar. We used the RadioAstron (RA) space radiotelescope together with two ground telescopes:…

Solar and Stellar Astrophysics · Physics 2017-05-10 V. I. Shishov , T. V. Smirnova , C. R. Gwinn , A. S. Andrianov , M. V. Popov , A. G. Rudnitskiy , V. A. Soglasnov

Stochastic temporal wandering of the spin frequency $\nu$ of a rotation-powered pulsar (i.e.~the achromatic component of timing noise unrelated to interstellar propagation) affects the accuracy with which the secular braking torque can be…

High Energy Astrophysical Phenomena · Physics 2023-05-17 Andrés F. Vargas , Andrew Melatos

In this paper, a method is proposed to determine the basic properties of $\gamma$-ray loud blazars, among them the central black hole mass, M, the Doppler factor, $\delta$, the propagation angle of the $\gamma$-rays with respect to the…

Astrophysics · Physics 2007-05-23 K. S. Cheng , J. H. Fan , L. Zhang

A mathematical algorithm is described for calculating the minimum distance between prisms and the allowable prism insertion depth into the laser beam when solving the general problem of intracavity group delay dispersion (GDD) compensation.…

High-energy gamma rays are a valuable tool for studying particle acceleration and radiation in the magnetospheres of energetic pulsars. The six or more pulsars seen by CGRO/EGRET show that: the light curves usually have double-peak…

Astrophysics · Physics 2009-11-06 David J. Thompson

Identifying as many gamma-ray pulsars as possible in the Fermi Large Area Telescope (LAT) data helps test pulsar emission models by comparing predicted and observed properties for a large, varied sample with as little selection bias as…

Fast radio bursts are radio transients observed mainly around 1.5 GHz. Their peak frequency decreases at a rate of 100 ~ 500 MHz/s and some of them have a broader pulse with an exponentially decaying tail. Common assumptions for fast radio…

High Energy Astrophysical Phenomena · Physics 2017-08-30 Qiwu Song , Yu Huang , Hengqiang Feng , Lei Yang , Tuanhui Zhou , Qingyu Luo , Tengfei Song , Xuefei Zhang , Yu Liu , Guangli Huang

Soon after the discovery of radio pulsars in 1967, the pulsars are identified as strongly magnetic (typically $10^{12}$G) rapidly rotating ($\sim 10^{2}-0.1$ Hz) neutron stars. However, the mechanism of particle acceleration in the pulsar…

Astrophysics · Physics 2008-11-26 Tomohide Wada , Shinpei Shibata

Time variable delays due to radio wave propagation in the ionized interstellar medium are a substantial source of error in pulsar timing array efforts. We describe the physical origin of these effects, discussing dispersive and scattering…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Dan Stinebring

Recent TeV observations of nearby pulsars with the HAWC telescope have been interpreted as evidence that the diffusion of high-energy electrons and positrons within pulsar wind nebulae is highly inefficient compared to the rest of the…

High Energy Astrophysical Phenomena · Physics 2018-06-27 Stefano Profumo , Javier Reynoso-Cordova , Nicholas Kaaz , Maya Silverman

Up to November 2022, 267 pulsars have been discovered in 36 globular clusters (GCs). In this paper, we present our studies on the distribution of GC pulsar parameters and the detection efficiency. The power law relation between the average…

High Energy Astrophysical Phenomena · Physics 2023-03-20 De-Jiang Yin , Li-Yun Zhang , Bao-Da Li , Ming-Hui Li , Lei Qian , Zhichen Pan

Using archival as well as freshly acquired data, we assess the X-ray behaviour of the Fermi/LAT gamma-ray pulsars listed in the First Fermi source catalog. After revisiting the relationships between the pulsars' rotational energy losses and…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Martino Marelli , Andrea De Luca , Patrizia A. Caraveo

A primary goal of integral field spectroscopic (IFS) surveys is to provide a statistical census of galaxies classified by their internal kinematics. As a result, the observational spin parameter, $\lambda_R$, has become one of the most…

Astrophysics of Galaxies · Physics 2018-11-28 K. E. Harborne , C. Power , A. S. G. Robotham , L. Cortese , D. S. Taranu

Using a theoretical model describing pulse shapes, we have clarified the relations between the observed pulses and their corresponding timescales, such as the angular spreading time, the dynamic time as well as the cooling time. We find…

Astrophysics · Physics 2008-11-26 Zhibin Zhang , G. Z. Xie , J. G. Deng , B. T. Wei
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