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Related papers: Crab pulsar spectrum: a non-extensive approach

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The paper presents an analysis of dual-polarization observations of the Crab pulsar obtained on the 64-m Kalyazin radio telescope at 600 MHz with a time resolution of 250 ns. A lower limit for the intensities of giant pulses is estimated by…

We apply a synchro-curvature spectral emission model based on characterizing the dynamics of magnetospheric particles to fit the phase-average spectra of the most extended database for the non-thermal spectra of pulsars. We consider 36…

High Energy Astrophysical Phenomena · Physics 2019-09-25 Diego F. Torres , Daniele Vigano , Francesco Coti Zelati , Jian Li

The data collected by ATIC, PPB-BETS, FERMI-LAT and HESS all indicate that there is an electron/positron excess in the cosmic ray energy spectrum above $\sim$ 100 GeV, although different instrumental teams do not agree on the detailed…

High Energy Astrophysical Phenomena · Physics 2013-01-18 Yi-Zhong Fan , Bing Zhang , Jin Chang

The pulsar wind nebula CTB 87 (G74.9+1.2) is one of the sources emitting $\gamma$-rays with energies higher than 10 TeV, as measured by the Very Energetic Radiation Imaging Telescope Array System telescope (VERITAS). In this study, we…

High Energy Astrophysical Phenomena · Physics 2025-02-06 Gong Yunlu , Zhou Liancheng , Xia Qi , Zhang Haiyun , Fang Jun , Zhang Li

For polar-cap models based on electromagnetic cascades induced by curvature radiation of beam particles we calculate broad-band high-energy spe ctra of pulsed emission expected for classical ($\sim 10^{12}\G$) and millisecond pulsars ($\sim…

Astrophysics · Physics 2007-05-23 Bronislaw Rudak , Jaroslaw Dyks

We report detection and analysis of the largest low-frequency (200 - 231.25 MHz) sample of Crab giant pulses (GPs) reported in the literature. In total about 95000 GPs were detected. The observations were performed in 2024/2025 with the…

High Energy Astrophysical Phenomena · Physics 2025-10-15 M. Sokolowski , P. Kumar , S. Dhavali , B. W. Meyers , N. D. R. Bhat , A. Bera , S. McSweeney

Recent observations of the Crab pulsar show no evidence for a spectral break in the infrared regime. It is argued that the observations are consistent with a power-law spectrum in the whole observable infrared - optical range. This is taken…

High Energy Astrophysical Phenomena · Physics 2015-05-18 C. -I. Björnsson , A. Sandberg , J. Sollerman

New polarimetric observations of the Crab pulsar at frequencies between 1.4 and 8.4 GHz are presented. Additional pulse components discovered in earlier observations (Moffett & Hankins 1996, astro-ph/9604163) are found to have high levels…

Astrophysics · Physics 2009-10-31 D. A. Moffett , T. H. Hankins

One of the most intriguing results from the gamma-ray instruments in orbit has been the detection of powerful flares from the Crab Nebula. These flares challenge our understanding of pulsar wind nebulae and models for particle acceleration.…

The fine structure and the variations of the optical pulse shape and phase of the Crab pulsar are studied on various time scales. The observations have been carried out on 4-m William Hershel and 6-m BTA telescopes with APD photon counter,…

Astrophysics · Physics 2008-11-26 S. Karpov , G. Beskin , A. Biryukov , V. Debur , V. Plokhotnichenko , M. Redfern , A. Shearer

Simultaneous dual-frequency observations of giant pulses from the Crab pulsar were performed at the frequencies of 61 and 111 MHz. It is shown that scattering of giant pulses from the Crab pulsar occurs at thick, and not at thin screen.

Astrophysics · Physics 2007-09-13 Alexander A. Ershov

To constrain the giant pulse (GP) emission mechanism and test the model of Lyutikov (2007) for GP emission, we have carried out a campaign of simultaneous observations of the Crab pulsar at gamma-ray (Fermi) and radio (Green Bank Telescope)…

Astrophysics of Galaxies · Physics 2011-01-28 A. V. Bilous , V. I. Kondratiev , M. A. McLaughlin , M. Mickaliger , S. M. Ransom , M. Lyutikov , G. I. Langston

Photometric data of the Crab pulsar, obtained in stroboscopic mode over a period of more than eight years, are presented here. The applied Fourier analysis reveals a faint 60 second modulation of the pulsar's signal, which we interpret as a…

Astrophysics · Physics 2007-05-23 Simon Vidrih , Andrej Cadez , Mirjam Galicic , Alberto Carraminana

We investigate a stationary pair production cascade in the outer magnetosphere of a spinning neutron star. The charge depletion due to a global current, causes a large electric field along the magnetic field lines. Migratory electrons…

Astrophysics · Physics 2007-05-23 Kouichi Hirotani , Shinpei Shibata

We have observed the pulsar in the Crab Nebula at high radio frequencies and high time resolution. We present continuously sampled data at 640-ns time resolution, and individual bright pulses recorded at down to 0.25-ns time resolution.…

High Energy Astrophysical Phenomena · Physics 2015-06-23 T. H. Hankins , G. Jones , J. A. Eilek

Gamma-ray bursts (GRBs) are cosmological explosions which carry valuable information from the distant past of the expanding universe. One of the greatest discoveries in modern cosmology is the finding of the accelerated expansion of the…

High Energy Astrophysical Phenomena · Physics 2016-06-15 Rupal Basak , A. R. Rao

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

Correlations among pulse properties in the prompt emission of long GRBs can potentially be used as cosmological distance indicators to estimate redshifts of GRBs to which these pulses belong. We demonstrate application of this technique to…

High Energy Astrophysical Phenomena · Physics 2009-06-25 Jon Hakkila , P. Chris Fragile , Timothy W. Giblin

We calculate the spectrum of blast wave models of gamma-ray burst sources, for various assumptions about the magnetic field density and the relativistic particle acceleration efficiency. For a range of physically plausible models we find…

Astrophysics · Physics 2011-09-30 P. Meszaros , M. J. Rees , H. Papathanassiou

We investigate polarization of high-energy emissions from the Crab pulsar in the frame work of the outer gap accelerator, following previous works of Cheng and coworkers. The recent version of the outer gap, which extends from inside the…

Astrophysics · Physics 2016-08-31 J. Takata , H. -K. Chang , K. S. Cheng
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