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

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The Crab Nebula is the brightest source in the very-high-energy (VHE) gamma-ray sky and one of the best studied non-thermal objects. The dominant VHE emission mechanism is believed to be inverse Compton scattering of low energy photons on…

High Energy Astrophysical Phenomena · Physics 2026-03-31 Kevin Meagher

The linear polarisation fraction and angle of the hard X-ray emission from the Crab provide unique insight into high energy radiation mechanisms, complementing the usual imaging, timing and spectroscopic approaches. Results have recently…

High Energy Astrophysical Phenomena · Physics 2018-03-14 M. Chauvin , H. -G. Florén , M. Friis , M. Jackson , T. Kamae , J. Kataoka , T. Kawano , M. Kiss , V. Mikhalev , T. Mizuno , H. Tajima , H. Takahashi , N. Uchida , M. Pearce

The Crab nebula has proved to be the nearest to a standard candle in VHE $\gamma-$ ray astronomy. Results on the gamma ray emission from the nebula at various energies have come in the last decade mostly from imaging telescopes. The aim of…

The frequency dependence of normal pulsar radio emission is typically observed to be a power law, with some indications of a flattening or turnover at low frequencies ($<100$ MHz). The spectrum of the Crab pulsar's giant pulse emission has…

High Energy Astrophysical Phenomena · Physics 2018-07-13 B. W. Meyers , S. E. Tremblay , N. D. R. Bhat , R. M. Shannon

The Crab Pulsar is a relatively young neutron star. The pulsar is the central star in the Crab Nebula, a remnant of the supernova SN 1054, which was observed on Earth in the year 1054. The Crab Pulsar has been extensively observed in the…

Astrophysics of Galaxies · Physics 2015-05-14 Fermi Collaboration , Fermi Pulsar Timing Consortium

The CANGAROO experiment has observed gamma-ray above 7TeV from the Crab pulsar/nebula at large zenith angle in Woomera, South Australia. We report the CANGAROO data taken in 1992, 1993 and 1995, from which it appears that the energy…

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

A dedicated stroboscopic device was used to obtain optical spectra of the Crab main-pulse and inter-pulse as well as the spectrum of the underlying nebula when the pulsar is turned off. As the nebular emission is very inhomogeneous, our…

Astrophysics · Physics 2009-10-31 Alberto Carraminana , Andrej Cadez , Tomaz Zwitter

In recent years, surprise discoveries of pulsed emission from the Crab and Vela pulsars above 100 GeV have drawn renewed attention to this largely unexplored region of the energy range. In this paper, we discuss example light curves due to…

High Energy Astrophysical Phenomena · Physics 2018-08-22 Christo Venter , Monica Barnard , Alice K. Harding , Constantinos Kalapotharakos

The Crab Nebula emits bright non-thermal radiation from radio to the most energetic photons. The underlying physical model of a relativistic wind from the pulsar terminating in a hydrodynamic standing shock remains unchanged since the early…

High Energy Astrophysical Phenomena · Physics 2023-03-08 Ludmilla Dirson , Dieter Horns

There are now a half dozen young pulsars detected in high energy photons by the Compton GRO, showing a variety of emission efficiencies and pulse profiles. We present here a calculation of the pattern of high energy emission on the sky in a…

Astrophysics · Physics 2009-10-22 Roger W. Romani , I. -A. Yadigaroglu

Aims. The Crab nebula displayed a large gamma-ray flare on September 18, 2010. To more closely understand the origin of this phenomenon, we analyze the INTEGRAL (20-500 keV) and FERMI (0.1-300 GeV) data collected almost simultaneously…

High Energy Astrophysical Phenomena · Physics 2015-05-20 M. Balbo , R. Walter , C. Ferrigno , P. Bordas

A model of an accelerated expansion of the Crab Nebula powered by the spinning-down Crab pulsar is proposed, in which time dependence of the acceleration is connected with evolution of pulsar luminosity. Using recent observational data, we…

Astrophysics · Physics 2011-05-23 M. Bejger , P. Haensel

The population of gamma-ray pulsars, including Crab observed in the TeV range, and Vela detected above 50 GeV, challenges existing models of pulsed high-energy emission. Such models should be universally applicable, yet they should account…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Iwona Mochol , Jerome Petri

Recent observations of the Crab Nebula (Rudy et al 2015) have maintained its reputation for high energy astrophysical enlightenment and its use as a testbed for theories of the behaviour of magnetized, relativistic plasma. In particular,…

High Energy Astrophysical Phenomena · Physics 2015-10-20 Yajie Yuan , Roger Blandford

Radio giant pulses provide a unique opportunity to study the pulsar radio emission mechanism in exquisite detail. Previous studies have revealed a wide range of properties and phenomena, including extraordinarily high brightness…

High Energy Astrophysical Phenomena · Physics 2015-07-15 Glenn Jones

The giant gamma-ray flares of the Crab nebula discovered by AGILE and Fermi observatories came as a surprise and have challenged the existing models of pulsar wind nebulae. We have carried out an analysis of 10.5 years of Fermi-LAT…

High Energy Astrophysical Phenomena · Physics 2020-11-23 M. S. Pshirkov , B. A. Nizamov , A. M. Bykov , Yu. A. Uvarov

A statistical scenario is proposed to explain the $\gamma$-ray variability and flares of the Crab nebula, which were observed recently by the Fermi/LAT. In this scenario electrons are accelerated in a series of knots, whose sizes follow a…

High Energy Astrophysical Phenomena · Physics 2011-03-09 Qiang Yuan , Peng-Fei Yin , Xue-Feng Wu , Xiao-Jun Bi , Siming Liu , Bing Zhang

We present the results of the search for a correlation between giant radio pulses (GRPs) at 1.4 GHz and hard X-rays at 15-75 keV from the Crab pulsar. We made simultaneous ground and satellite observations of the Crab pulsar over 12 hours…

Our high time resolution observations of individual giant pulses in the Crab pulsar show that both the time and frequency signatures of the interpulse are distinctly different from those of the main pulse. Giant main pulses can occasionally…

Astrophysics · Physics 2007-05-23 J. A. Eilek , T. H. Hankins