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相关论文: Interstellar Scintillation od Pulsar B0809+74

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Results of long time observations of the pulsar B0950+08 are given. These observations were carried out at the LPA radio telescope at the frequency of 111 MHz from January of 2016 to May of 2019 (450 days). A strong variability in emission…

高能天体物理现象 · 物理学 2022-03-14 V. M. Malofeev , I. F. Malov , O. I. Malov , D. A. Teplykh

Cosmic ray electrons and positrons are tracers of particle propagation in the interstellar medium (ISM). A recent measurement performed using H.E.S.S. extends the all-electron (electron+positron) spectrum up to 20TeV, probing very local…

高能天体物理现象 · 物理学 2019-01-08 R. López-Coto , R. D. Parsons , J. A. Hinton , G. Giacinti

The propagation of radio waves from distant compact radio sources through turbulent interstellar plasma in our Galaxy causes these sources to twinkle, a phenomenon called interstellar scintillation. Such scintillations are a unique probe of…

We present a robust approach to incorporating models for the time-variable broadening of the pulse profile due to scattering in the ionized interstellar medium into profile-domain pulsar timing analysis. We use this approach to…

天体物理仪器与方法 · 物理学 2017-04-12 L. Lentati , M. Kerr , S. Dai , R. M. Shannon , G. Hobbs , S. Oslowski

We report multifrequency measurements of scatter broadening times for nine highly dispersed pulsars over a wide frequency range (0.6 -- 4.9 GHz). We find the scatter broadening times to be larger than expected and to scale with frequency…

天体物理学 · 物理学 2009-11-07 O. Loehmer , M. Kramer , D. Mitra , D. R. Lorimer , A. G. Lyne

We present multi-frequency observations with the Very Long Baseline Array of the compact double radio source B2 2050+36. Our observations are at 0.33, 0.61, 1.67, 2.3, and 8.4 GHz, with the 0.61 GHz observations forming the third epoch of…

天体物理学 · 物理学 2009-11-06 T. Joseph W. Lazio , A. L. Fey

The scintillation of pulsars reveals small-scale structure of the interstellar medium. A powerful technique for characterizing the scintillating structures (screens) combines analysis of scintillation arcs and very long baseline…

高能天体物理现象 · 物理学 2025-10-21 Ashley M. Stock , Fardin Syed , Marten H. van Kerkwijk , Rebecca Lin , Franz Kirsten , Ue-Li Pen

We report a direct measurement of the electron density turbulence parameter $C_1$, enabled by 550-750~MHz baseband observations with the upgraded Giant Metrewave Radio Telescope. The parameter $C_1$ depends on the power law index of the…

高能天体物理现象 · 物理学 2025-08-19 Visweshwar Ram Marthi , Yogesh Maan

We report on observations of PSR B1508+55's scintillation at the Effelsberg 100-m telescope spanning from early 2020 to early 2022. In the autumn of 2020, close to the time the pulsar was predicted to cross echoes in its pulse profile, a…

高能天体物理现象 · 物理学 2023-02-06 Tim Sprenger , Robert Main , Olaf Wucknitz , Geetam Mall , Jason Wu

This paper considers scattering screens that have arbitrary spatial variations of scattering strength transverse to the line of sight, including screens that are spatially well confined, such as disks and filaments. We calculate the…

天体物理学 · 物理学 2009-10-31 J. M. Cordes , T. Joseph W. Lazio

Observations over the last two decades have shown that a significant fraction of all flat-spectrum, extragalactic radio sources exhibit flux density variations on timescales of a day or less at frequencies of several GHz. It has been…

The circumgalactic medium (CGM) is poorly constrained at the sub-parsec scales relevant to turbulent energy dissipation and regulation of multi-phase structure. Fast radio bursts (FRBs) are sensitive to small-scale plasma density…

星系天体物理 · 物理学 2025-07-25 S. K. Ocker , M. Chen , S. P. Oh , P. Sharma

We report the detection of giant pulse emission from PSR~B0950+08 in 12 hours of observations made simultaneously at 42~MHz and 74~MHz, using the first station of the Long Wavelength Array, LWA1. We detected 275 giant pulses (in 0.16\% of…

高能天体物理现象 · 物理学 2016-08-10 Jr-Wei Tsai , John H Simonetti , Bernadine Akukwe , Brandon Bear , Jonathan D Gough , Peter Shawhan , Michael Kavic

We compare signal and noise for observations of the scintillating pulsar B0834+06, using very-long baseline interferometry and a single-dish spectrometer. Comparisons between instruments and with models suggest that amplitude variations of…

星系天体物理 · 物理学 2015-05-27 C. R. Gwinn , M. D. Johnson , T. V. Smirnova , D. R. Stinebring

The pulse profile of pulsar gives geometric information about pulsar's radiation model. After investigating the pulse profiles of PSR B1642-03 and PSR B0950+08, we calculate the ratios of beam width and the emission height between different…

天体物理学 · 物理学 2007-05-23 X. H. Cui , K. J. Lee , G. J. Qiao , Y. L. Yue , R. X. Xu , H. G. Wang

We present multi-wavelength scatter broadening observations of 47 pulsars, made with the Giant Metre-wave Radio Telescope (GMRT), Ooty Radio Telescope (ORT) and Long Wavelength Array (LWA). The GMRT observations have been made in the phased…

高能天体物理现象 · 物理学 2017-09-13 M. A. Krishnakumar , Bhal Chandra Joshi , P. K. Manoharan

I use a method based on interstellar scintillations for discerning information about source sizes on scales less than one micro-arc sec. I use a comprehensive model for a pulsar signal, scintillated amplitude modulated noise, that includes…

天体物理学 · 物理学 2007-05-23 J. M. Cordes

We present a comprehensive interstellar scintillation (ISS) study of the radio-loud magnetar XTE~J1810$-$197, based on six years of multi-frequency monitoring (2018$-$2024) with the Shanghai Tian Ma Radio Telescope (TMRT) at 7.0, 8.6, and…

Context. Pulsars scintillate. Dynamic spectra show brightness variation of pulsars in the time and frequency domain. Secondary spectra demonstrate the distribution of fluctuation power in the dynamic spectra. Aims. Dynamic spectra strongly…

高能天体物理现象 · 物理学 2018-10-31 P. F. Wang , J. L. Han , Lei Han , JianHui Zhang , JunQiang Li , Chen Wang , Jun Han , Tao Wang , X. Y. Gao

We report the electron density in a plasma tail of Comet ISON (C/2012 S1) derived from interplanetary scintillation (IPS) observations during November 1--28, 2013. Comet ISON showed a well-developed plasma tail (longer than 2.98 x 10^{7}…

地球与行星天体物理 · 物理学 2015-03-02 Tomoya Iju , Shinsuke Abe , Munetoshi Tokumaru , Ken'ichi Fujiki