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相关论文: Radio Scintillation due to Discontinuities in the …

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We observed the scintillation pattern of nine bright pulsars at 324 MHz and three at 1.68 GHz and analyzed the wavenumber spectrum which is related to electron density variations of the plasma turbulence of the interstellar medium. For all…

星系天体物理 · 物理学 2022-12-21 N. Bartel , M. S. Burgin , E. N. Fadeev , M. V. Popov , N. Ronaghikhameneh , T. V. Smirnova , V. A. Soglasnov

Refractive scintillation effects are powerful techniques for discriminating between different models proposed for the electron density fluctuation spectrum in the ISM. Data from our long-term scintillation study of 18 pulsars in the DM…

天体物理学 · 物理学 2009-10-31 N. D. Ramesh Bhat , Yashwant Gupta , A. Pramesh Rao

Refractive Interstellar Scintillation (RISS) effects on pulsar signals are powerful techniques for discriminating between different models that have been proposed for the power spectrum of plasma density fluctuations in the Interstellar…

天体物理学 · 物理学 2007-05-23 N. D. Ramesh Bhat , Yashwant Gupta , A. Pramesh Rao

We show that surface waves along interstellar current sheets closely aligned with the line of sight lead to pulsar scintillation properties consistent with those observed. This mechanism naturally produces the length and density scales of…

星系天体物理 · 物理学 2015-06-15 Ue-Li Pen , Yuri Levin

We studied the turbulence spectrum of the local interstellar plasma in the direction of PSR J0437-4715, on the basis of our observations and those reported earlier by others. We combine these data to form a structure function for the…

天体物理学 · 物理学 2009-11-11 T. V. Smirnova , C. R. Gwinn , V. I. Shishov

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 interstellar scintillation observed in radio pulsars arises from interference between electromagnetic waves scattered by electron density fluctuations in the turbulent interstellar plasma, providing a critical tool for probing the…

Weak interstellar scintillations of pulsar B0809+74 were observed at two epochs using a 30m EISCAT antenna at 933 MHz. These have been used to constrain the spectrum, the distribution and the transverse velocity of the scattering plasma…

天体物理学 · 物理学 2015-06-24 Barney Rickett , Bill Coles , Jussi Markkanen

Observations of radio signals from distant pulsars provide a valuable tool for investigation of interstellar turbulence. The time-shapes of the signals are the result of pulse broadening by the fluctuating electron density in the…

天体物理学 · 物理学 2007-05-23 Stanislav Boldyrev , Carl R. Gwinn

Context. Interstellar scintillation (ISS) of pulsar emission can be used both as a probe of the ionised interstellar medium (IISM) and cause corruptions in pulsar timing experiments. Of particular interest are so-called scintillation arcs…

Observations reveal a uniform Kolmogorov turbulence throughout the diffuse ionized interstellar medium (ISM) and supersonic turbulence preferentially located in the Galactic plane. Correspondingly, we consider the Galactic distribution of…

星系天体物理 · 物理学 2017-01-25 Siyao Xu , Bing Zhang

Interstellar scintillation can be used to probe transverse sizes of radio sources on scales inaccessible to the nominal resolution of any terrestrial telescope, e.g. $\lesssim 10^{-6}$ arc sec. Methodology is presented that exploits this…

天体物理学 · 物理学 2007-05-23 J. M. Cordes

It was recently suggested by Boldyrev & Gwinn that the characteristics of radio scintillations from distant pulsars are best understood if the interstellar electron-density fluctuations that cause the time broadening of the radio pulses…

天体物理学 · 物理学 2010-11-11 Stanislav Boldyrev , Arieh Konigl

Scintillation spectra of some pulsars have suggested the existence of $\lesssim$ AU scale density structures in the ionized interstellar medium, whose astrophysical correspondence is still a mystery. The detailed study of Brisken et al.…

星系天体物理 · 物理学 2021-09-28 Xun Shi

Radio-wave scintillation observations reveal a nearly Kolmogorov spectrum of density fluctuations in the ionized interstellar medium. Although this density spectrum is suggestive of turbulence, no theory relevant to its interpretation…

天体物理学 · 物理学 2009-11-06 Yoram Lithwick , Peter Goldreich

Results from new observations of pulsars using the Ooty Radio Telescope (ORT) are used for investigating the structure of the Local Interstellar Medium (LISM). The observations show anomalous scintillation effects towards several nearby…

天体物理学 · 物理学 2007-05-23 N. D. Ramesh Bhat , Yashwant Gupta , A. Pramesh Rao , P. B. Preethi

Radio waves propagating through the interstellar medium are influenced by variations in plasma density. For spatially localised plasma structures along the line of sight, time-delay Doppler analyses of pulsars often reveal scintillation…

高能天体物理现象 · 物理学 2026-05-15 Tobias Kramer

Spectral features absorbed against some radio quasars exhibit ~50mJy variations, with the lines varying both relative to the continuum and, when several lines are present, even relative to one another. We point out that such variability can…

天体物理学 · 物理学 2009-11-10 Jean-Pierre Macquart

Pulsar scintillation allows a glimpse into small-scale plasma structures in the interstellar medium, if we can infer their properties from the scintillation pattern. With Very Long Baseline Interferometry and working in delay-delay rate…

天体物理仪器与方法 · 物理学 2019-08-07 Dana Simard , Ue-Li Pen , Visweshwar Ram Marthi , Walter Brisken
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