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Related papers: Pulsed optical emission from Geminga

200 papers

Integrated ground-based and HST optical studies of isolated neutron stars have provided important independent datasets in the determination of emission activity, particularly in the fitting of anticipated Rayleigh-Jeans extrapolations from…

Astrophysics · Physics 2007-05-23 A. Golden , A. Shearer

$\gamma$-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

We report the detection of pulsed gamma-ray emission from the fast millisecond pulsars (MSPs) B1937+21 (also known as J1939+2134) and B1957+20 (J1959+2048) using 18 months of survey data recorded by the \emph{Fermi} Large Area Telescope…

We present the detection of pulsed gamma-ray emission from the Crab Pulsar above 100 GeV with the VERITAS array of atmospheric Cherenkov telescopes. Gamma-ray emission at theses energies is not expected in present pulsar models. We find…

High Energy Astrophysical Phenomena · Physics 2019-08-13 A. Nepomuk Otte

We have identified an optical binary with orbital period P_b=4488s as the probable counterpart of the Fermi source 2FGL J1653.6-0159. Although pulsations have not yet been detected, the source properties are consistent with an evaporating…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Roger W. Romani , Alexei V. Filippenko , S. Bradley Cenko

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

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 the optical polarization of a gamma ray burst (GRB) afterglow, obtained 203 seconds after the initial burst of gamma rays from GRB 060418, using a ring polarimeter on the robotic Liverpool Telescope. Our robust (2-sigma) upper…

The First \fermi-LAT Catalog of Sources Above 10 GeV reported evidence of pulsed emission above 25 GeV from 12 pulsars, including the Vela pulsar, which showed evidence of pulsation at $>37$ GeV energy bands. Using 62 months of \fermi-LAT…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Gene C. K. Leung , J. Takata , C. W. Ng , A. K. H Kong , P. H. T. Tam , C. Y. Hui , K. S. Cheng

One fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high-end region of a pulsar's spectrum would shed light on this question. By developing a new electronic trigger, we…

Astrophysics · Physics 2009-04-08 The MAGIC Collaboration , E. Aliu

We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time-resolved photometry using optical data obtained by the TAROT telescope, using BAT…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Alain Klotz , B. Gendre , J. L. Atteia , Michel Boër , David M. Coward , Alan C. Imerito

Gamma-ray bursts of short duration may harbor vital clues to the range of phenomena producing bursts. However, recent progress from the observation of optical counterparts has not benefitted the study of short bursts. We have searched for…

The prompt optical emission of GRB 990123 was uncorrelated to the gamma-ray light-curve and exhibited temporal properties similar to those of the steeply-decaying, early X-ray emission observed by Swift at the end of many bursts. These…

Astrophysics · Physics 2008-11-26 A. Panaitescu , P. Kumar

The discovery (Liang & Kargatis 1996), that the peak energy of time-resolved spectra of gamma-ray burst (GRB) pulses decays exponentially with fluence, is analytically shown to imply that the time-integrated photon number spectrum of a…

Astrophysics · Physics 2009-10-30 Felix Ryde , Roland Svensson

We investigate the behavior of the light pulse in $Lambda$-type cold atomic gases with two counterpropagating control lights with equal strength by directly simulating the dynamic equations and exploring the dispersion relation. Our…

Quantum Physics · Physics 2010-04-28 Ran Wei , Bo Zhao , Youjin Deng , Shuai Chen , Zeng-Bing Chen , Jian-Wei Pan

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

We have detected pulsed X-ray emission from the fastest millisecond pulsar known, PSR B1937+21 (P=1.558 msec), with ASCA. The pulsar is detected as a point source above $\sim 1.7$ keV, with no indication of nebulosity. The source flux in…

Astrophysics · Physics 2009-11-06 M. Takahashi

Using the outer gap model, we investigate the emission region for the multi-wavelength light curve from energetic pulsars. We assume that gamma-ray and non-thermal X-ray photons are emitted from a particle acceleration region in the outer…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Shota Kisaka , Yasufumi Kojima

The origin of the pulsed gamma-ray emission in pulsars remains an open issue. The combination of sensitive observations in the GeV domain by AGILE and {\em Fermi}-LAT and increasingly sophisticated numerical simulations have recently…

High Energy Astrophysical Phenomena · Physics 2018-11-26 Benoît Cerutti

We have observed the optical pulse profile of PSR B0656+14 in 10 phase bins at a high signal-to-noise ratio, and have measured the linear polarization profile over 30% of the pulsar period with some significance. The pulse profile is…

Astrophysics · Physics 2009-11-10 B. Kern , C. Martin , B. Mazin , J. P. Halpern