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Related papers: On the optical pulsations from the Geminga pulsar

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Recent optical/UV data of Geminga (Mignani et al. 1998) have strengthen the significance of the emission feature present over the thermal continuum best fitting the EUV/soft X-ray data. Here we present a phenomenological model interpreting…

Astrophysics · Physics 2007-05-23 A. Jacchia , F. De Luca , E. Lazzaro , P. A. Caraveo , R. P. Mignani , G. F. Bignami

Radio-quiet gamma-ray pulsars like Geminga may account for a number of the unidentified EGRET sources in the Galaxy. The number of Geminga-like pulsars is very sensitive to the geometry of both the gamma-ray and radio beams. Recent studies…

Astrophysics · Physics 2008-11-26 Alice K. Harding , Isabelle A. Grenier , Peter L. Gonthier

We discuss $\gamma$-ray emissions from the outer gap accelerators of middle-aged pulsars for part of the series of our studies. A two-dimensional electrodynamic model is used to solve the distribution of accelerating electric fields with…

Astrophysics · Physics 2009-11-13 J. Takata , H. -K. Chang

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

(abridged) Although discovered 40 years ago, the emission mechanism responsible for the observed pulsar radiation remains unclear. However, the high-energy pulsed emission is usually explained in the framework of either the polar cap or the…

High Energy Astrophysical Phenomena · Physics 2015-05-13 J. Petri

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

We present optical data which shows that G", the optical counterpart of the gamma-ray pulsar Geminga, pulses in B with a period of 0.237 seconds. The similarity between the optical pulse shape and the gamma-ray light curve indicates that a…

We report a search for radio continuum emission from the gamma-ray pulsar Geminga. We have used the VLA to image the location of the optical counterpart of Geminga at 74 and 326 MHz. We detect no radio counterpart. We derive upper limits to…

Astrophysics · Physics 2009-10-31 Namir E. Kassim , T. Joseph W. Lazio

The radiation of pulsars have been observed for many years. A few pulsars are discovered to have both radio and gamma-ray emission. Many models on pulsar radiation have been developed, but so far we are still lacking an elaborate model…

Astrophysics · Physics 2009-09-29 G. J. Qiao , K. J. Lee , H. G. Wang , R. X. Xu

Electrons/positrons produced in a pulsar magnetosphere emit synchrotron radiation, which is widely believed as the origin of the non-thermal X-ray emission detected from pulsars. Particles are produced by curvature photons emitted from…

High Energy Astrophysical Phenomena · Physics 2015-03-03 Shota Kisaka , Shuta J. Tanaka

A deep Very Large Array observation of the Geminga pulsar field led to the discovery, at a higher than 10 sigma significance level, of radio emission trailing the neutron star proper motion. This 10-arcsec-long radio feature, detected with…

High Energy Astrophysical Phenomena · Physics 2013-01-17 A. Pellizzoni , F. Govoni , P. Esposito , M. Murgia , A. Possenti

We study the synchrotron radiation as the observed non-thermal X-ray emission from old pulsars ($\gtrsim1-10$Myr) to investigate the particle acceleration in their magnetospheres. We assume that the power-law component of the observed X-ray…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Shota Kisaka , Shuta J. Tanaka

$\gamma$-ray spectra of pulsars have been mostly studied in a phenomenological way, by fitting them to a cut-off power-law function. Here, we analyze a model where pulsed emission comes from synchro-curvature processes in a gap. We…

High Energy Astrophysical Phenomena · Physics 2015-06-24 Daniele Viganò , Diego F. Torres

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

Radiation of both the outer gaps and the neutron star surface is considered for a Vela-like pulsar near the death line. It is shown that if such a pulsar is close enough to the death line, its optical, UV and X-ray emission has to increase.…

Astrophysics · Physics 2009-10-22 Vladimir V. Usov

I have searched for pulsed radio emission from the Geminga pulsar and for the nearby isolated neutron star 1RX J1308.6+2127 (RBS 1223) at the frequency of 111 MHz. No pulsed signals were detected from these sources. Upper limits for mean…

Astrophysics · Physics 2007-08-31 Alexander A. Ershov

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

The high-energy emission mechanisms based on the radio photon reprocessing by the ultrarelativistic plasma particles in the open field line tube of a pulsar are considered. The particles are believed to acquire relativistic gyration…

Astrophysics of Galaxies · Physics 2009-04-28 S. A. Petrova

We report on the \textit{Fermi}-LAT observations of the Geminga pulsar, the second brightest non-variable GeV source in the $\gamma$-ray sky and the first example of a radio-quiet $\gamma$-ray pulsar. The observations cover one year, from…

High Energy Astrophysical Phenomena · Physics 2016-04-13 LAT Collaboration , A. A. Abdo

The Vela and Geminga pulsars are rotation powered neutron stars, which have been identified in various spectral domains, from the near-infrared to hard $\gamma$-rays. In the near-infrared they exhibit tentative emission excesses, as…

Solar and Stellar Astrophysics · Physics 2011-11-16 Andrey A. Danilenko , Dmitry A. Zyuzin , Yuri A. Shibanov , Sergey V. Zharikov
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