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Related papers: Single Pulse Variability in Gamma-ray Pulsars

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Geminga is the first pulsar around which a remarkable TeV gamma-ray halo extending over a few degrees was discovered by MILAGRO, HAWC and later by H.E.S.S., and by Fermi-LAT in the GeV band. More middle-aged pulsars have exhibited gamma-ray…

High Energy Astrophysical Phenomena · Physics 2024-09-25 Silvia Manconi , Jooyun Woo , Ruo-Yu Shang , Roman Krivonos , Claudia Tang , Mattia Di Mauro , Fiorenza Donato , Kaya Mori , Charles J. Hailey

We report on dual-frequency radio polarimetry observations of two young, energetic pulsars, PSRs J0940-5428 and J1301-6305. These were among the first Vela-like pulsars discovered in the Parkes Multibeam survey. We conducted observations of…

Astrophysics · Physics 2008-11-26 F. Crawford , C. L. Tiffany

In recent years, the Fermi-LAT gamma-ray telescope has detected a population of over 160 gamma-ray pulsars, which has enabled the detailed study of electromagnetic radiation from pulsars at energies above 100 MeV. Further, since the…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Gregory T. Richards

Pulsars are known to display short-term variability. Recently, examples of longer-term emission variability have emerged that are often correlated with changes in the rotational properties of the pulsar. To further illuminate this…

High Energy Astrophysical Phenomena · Physics 2016-01-27 P. R. Brook , A. Karastergiou , S. Johnston , M. Kerr , R. M. Shannon , S. J. Roberts

Pulsed emission from the bright EGRET pulsars - Vela, Crab, and Geminga - extends up to 10 GeV. The generic gamma lightcurve features two peaks separated by 0.4 to 0.5 in phase. According to Thompson (2001) the lightcurve becomes…

Astrophysics · Physics 2009-11-06 J. Dyks , B. Rudak

The spectra of only a few pulsars are known in the low-energy gamma-ray region around 1 Mev. We searched for point sources of gamma-radiation in the 0.3-1 and 1-8 Mev bandpasses at the location of known radio and X-ray pulsars. Single…

High Energy Astrophysical Phenomena · Physics 2011-04-21 Joseph F. Dolan

Fermi-LAT observations revealed that each GeV phase-folded light-curve (aka. phaseogram) of the Crab, Geminga, Dragonfly and Vela pulsars consists of two pulses (P1 & P2) and a "Bridge" between them. There is clearly a "bump" at the Bridge…

High Energy Astrophysical Phenomena · Physics 2025-08-28 Paul K. H. Yeung , Dmitry Khangulyan , Takayuki Saito

Individual pulses from pulsars have intensity-phase profiles that differ widely from pulse to pulse, from the average profile, and from phase to phase within a pulse. Widely accepted explanations for pulsar radio emission and its time…

Astrophysics · Physics 2009-11-07 Iver H. Cairns , S. Johnston , P. Das

Geminga was first detected as a gamma-ray point source by the SAS-2 gamma-ray satellite observatory and the COS-B X-ray satellite observatory. Subsequent observations have identified Geminga as a heavily obscured radio-quiet pulsar…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Andy Flinders

Because of the relatively broad angular resolution of current gamma-ray instruments in the MeV-GeV energy range, the photons of a given source are mixed with those coming from nearby sources or diffuse background. This source confusion…

Instrumentation and Methods for Astrophysics · Physics 2019-02-06 P. Bruel

Prompted by the Fermi LAT discovery of a radio-quiet gamma-ray pulsar inside the CTA 1 supernova remnant, we obtained a 130 ks XMM-Newton observation to assess the timing behavior of this pulsar. Exploiting both the unprecedented photon…

High Energy Astrophysical Phenomena · Physics 2015-05-20 P. A. Caraveo , A. De Luca , M. Marelli , G. F. Bignami , P. S. Ray , P. M. Saz-Parkinson , G. Kanbach

We report the discovery of gamma-ray pulsations from the nearby isolated millisecond pulsar PSR J0030+0451 with the Large Area Telescope (LAT) on the \emph{Fermi} Gamma-ray Space Telescope (formerly GLAST). This discovery makes PSR…

High Energy Astrophysical Phenomena · Physics 2009-07-22 LAT Collaboration

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

We report here our observations at 35 MHz and 327 MHz made in the direction of the Gamma Ray pulsar Geminga. Based on the observed absence of any significant pulsed emission from this source above our detection thresholds at the two…

Astrophysics · Physics 2007-05-23 R. Ramachandran , A. A. Deshpande , C. Indrani

We present measurements of the size of the Vela pulsar in 3 gates across the pulse, from observations of the distribution of intensity. We calculate the effects on this distribution of noise in the observing system, and measure and remove…

We present the results of deep X-ray and gamma-ray observations of the Geminga pulsar obtained in the final years of the ASCA and CGRO missions, and an upper limit from RXTE. A phase-connected ephemeris from the gamma-rays is derived that…

Astrophysics · Physics 2009-11-07 M. S. Jackson , J. P. Halpern , E. V. Gotthelf , J. R. Mattox

We report on orbital modulation of the 100-600 MeV gamma-ray emission of the $P_{\rm B}=4.6$ hr millisecond pulsar binary PSR J2339$-$0533 using 11 yr of Fermi Large Area Telescope data. The modulation has high significance (chance…

High Energy Astrophysical Phenomena · Physics 2020-07-08 Hongjun An , Roger W. Romani , Matthew Kerr

The mechanisms of emission and changes in rotation frequency ('glitching') of the Vela pulsar (J0835-4510) are not well understood. Further insight into these mechanisms can be achieved by long-term studies of integrated pulse width, timing…

High Energy Astrophysical Phenomena · Physics 2016-03-21 J. L. Palfreyman , J. M. Dickey , S. P. Ellingsen , I. R. Jones , A. W. Hotan

We report the results of the spectral and timing analysis of observations of the Vela pulsar with the Chandra X-ray Observatory. The spectrum shows no statistically significant spectral lines in the observed 0.25--8.0 keV band. It consists…

We study graviton-photon conversion in magnetosphere of a pulsar and explore the possibility of detecting high frequency gravitational waves with pulsar observations. It is shown that conversion of one polarization mode of photons can be…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Asuka Ito , Kazunori Kohri , Kazunori Nakayama