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Related papers: Pulsed optical emission from Geminga

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We report the Fermi Large Area Telescope discovery of gamma-ray pulsations from the 22.7 ms pulsar A in the double pulsar system J0737-3039A/B. This is the first mildly recycled millisecond pulsar (MSP) detected in the GeV domain. The 2.7 s…

High Energy Astrophysical Phenomena · Physics 2015-06-15 L. Guillemot , M. Kramer , T. J. Johnson , H. A. Craig , R. W. Romani , C. Venter , A. K. Harding , R. D. Ferdman , I. H. Stairs , M. Kerr

BGGSe is a newly developed nonlinear material that is attractive for ultrabroad frequency mixing and ultrashort pulse generation due to its comparably low dispersion and high damage threshold.In a first experiment, we show that a long…

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

Pulsed emission from gamma-ray pulsars originates inside the magnetosphere, from radiation by charged particles accelerated near the magnetic poles or in the outer gaps. In polar cap models, the high energy spectrum is cut off by magnetic…

Astrophysics · Physics 2009-10-31 Alice K. Harding

In 1993-1994 a series of observations of the X-ray pulsar GX 301-2 by HEXE onboard Mir-Kvant was made. A period of pulsations was measured (it varied between 675 and 678 s) and pulse profiles in different energy bands were produced. The…

We report on very high energy gamma-observations with the MAGIC Telescope of the pulsar PSR B1951+32 and its associated nebula, CTB 80. Our data constrain the cutoff energy of the pulsar to be less than 32 GeV, assuming the pulsed gamma-ray…

Astrophysics · Physics 2008-11-26 MAGIC Collaboration , J. Albert

A comprehensive temporal analysis has been performed on the 319 brightest GRBs with T90>2s from the BATSE current catalog. The rise times, fall times, full-widths at half maximum (FWHM), pulse amplitudes and pulse areas were measured and…

Astrophysics · Physics 2009-11-07 F. Quilligan , B. McBreen , L. Hanlon , S. McBreen , K. J. Hurley , D. Watson

We demonstrate that distinguishable gamma-ray burst pulses exhibit similar behaviors as evidenced by correlations among the observable pulse properties of duration, peak luminosity, fluence, spectral hardness, energy-dependent lag, and…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Jon Hakkila , Robert D. Preece

The Fermi Large Area Telescope receives $\ll$1 photon per rotation from any $\gamma$-ray pulsar. However, out of the billions of monitored rotations of the bright pulsars Vela (PSR~J0835$-$4510) and Geminga (PSR~J0633$+$1746), a few…

High Energy Astrophysical Phenomena · Physics 2022-08-03 Matthew Kerr

We report unsuccessful searches for pulsations from the neutron star RX J1836.2+5925 identified with the EGRET source 3EG J1835+5918. A 24 hr observation with the NRAO Green Bank Telescope at 820 MHz placed an upper limit on flux density of…

Astrophysics · Physics 2009-11-13 J. P. Halpern , F. Camilo , E. V. Gotthelf

The highly variable and energetic pulsed emission of a long gamma-ray burst (GRB) is thought to originate from local, rapid dissipation of kinetic or magnetic energy within an ultra-relativistic jet launched by a newborn compact object,…

We reanalyze the Fermi spectra of the Geminga and Vela pulsars. We find that the spectrum of Geminga above the break is exceptionally well approximated by a simple power law without the exponential cut-off, making Geminga's spectrum similar…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Maxim Lyutikov

We observed PSR J0437-4715 with the FUV-MAMA detector of the Hubble Space Telescope Imaging Spectrometer (STIS) to measure the pulsar's spectrum and pulsations. For the first time, UV emission from a millisecond pulsar is detected. The…

Astrophysics · Physics 2009-11-10 O. Kargaltsev , G. G. Pavlov , R. W. Romani

Giant pulses and giant micropulses from pulsars are distinguished from normal pulsed emission by their large fluxes, rarity, approximately power-law distribution of fluxes and, typically, occurrence in restricted phase windows. Here…

Astrophysics · Physics 2009-11-10 Iver H. Cairns

We have investigated the bimodal distribution of the duration of BATSE gamma-ray bursts (GRBs) by analyzing light curves of 64 ms time resolution. We define the average pulse width of GRBs from the auto-correlation function of GRB profiles.…

Astrophysics · Physics 2007-05-23 Wenfei Yu , Tipei Li , Mei Wu

In order to better understand the physical origin of short duration gamma-ray bursts (GRBs), we perform time-resolved spectral analysis on a sample of 70 pulses in 68 short GRBs with burst duration $T_{90}\lesssim2$ s detected by the…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Hüsne Dereli-Bégué , Asaf Pe'er , Felix Ryde

Geminga is an enigmatic radio-quiet gamma-ray pulsar located at a mere 250 pc distance from Earth. Extended very-high-energy gamma-ray emission around the pulsar has been detected by multiple water Cherenkov detector based instruments.…

High Energy Astrophysical Phenomena · Physics 2023-09-01 A. M. W. Mitchell , S. Caroff

The optical counterpart of the Gamma-Ray Burst GRB 970228, discovered by Groot et al. (IAU Circ. 6584), is also detected in the B and R frames obtained about 4 hours earlier at the Bologna Observatory. Our observations indicate a very…

Gamma-ray burst GRB 140430A was detected by the Swift satellite and observed promptly with the imaging polarimeter RINGO3 mounted on the Liverpool Telescope, with observations beginning while the prompt $\gamma$-ray emission was still…

We report on a very bright, long-duration gamma-ray burst (GRB), GRB~220426A, observed by \emph{Fermi} satellite. GRB~220426A with total duration of $T_{90}=6$~s is composed with two main pulses and some sub-peaks. The spectral analysis of…

High Energy Astrophysical Phenomena · Physics 2022-05-19 Li-Tao Deng , Da-Bin Lin , Li Zhou , Kai Wang , Xing Yang , Shu-Jin Hou , Jing Li , Xiang-Gao Wang , Rui-Jing Lu , En-Wei Liang
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