相关论文: 100 Microarcsecond Resolution VLBI Imaging of Anis…

We use VLBI imaging of the interstellar scattering speckle pattern associated with the pulsar PSR 0834+06 to measure the astrometric motion of its emission. The ~ 5AU interstellar baselines, provided by interference between speckles…

The parabolic arc phenomenon visible in the Fourier analysis of the scintillation spectra of pulsars provides a new method of investigating the small scale structure in the ionized interstellar medium (ISM). We report archival observations…

(Abridged) This paper reports new Very Large Array (VLA) and Very Long Baseline Array (VLBA) observations of the extragalactic source B1849+005 at frequencies between 0.33 and 15 GHz and the re-analysis of archival VLA observations at 0.33,…

We have detected a strong deflection of radio waves from the pulsar PSR B0834+06 in scintillation observations. Interference between the undeflected pulsar image and deflected subimages allows single dish interferometry of the interstellar…

The aim of our work was to study the spatial structure of inhomogeneities of interstellar plasma in the directions of five pulsars: B0823+26, B0834+06, B1237+25, B1929+10, and B2016+28. Observations of these pulsars were made with…

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…

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…

RadioAstron space-ground VLBI observations of the pulsar B0950+08, conducted with the 10-m space radio telescope in conjunction with the Arecibo 300-m telescope and Westerbork Synthesis Radio Telescope at a frequency of 324 MHz, were…

We have made high-resolution, high-sensitivity dynamic spectra of a sample of strong pulsars at 430 MHz with the Arecibo radiotelescope. For 4 pulsars we find faint but sharply delineated features in the secondary spectra. These are…

Interstellar scattering is known to broaden distant objects spatially and temporally. The latter aspect is difficult to analyse, unless the signals carry their own time stamps. Pulsars are so kind to do us this favour. Typically the…

High sensitivity interstellar scintillation and polarization observations of PSR~B0656+14 made at three epochs over a year using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) show that the scattering is dominated by two…

Our analysis of archival VLBI data of PSR 0834+06 revealed that its scintillation properties can be precisely modelled using the inclined sheet model (Pen & Levin 2014), resulting in two distinct lens planes. These data strongly favour the…

We report on the low Galactic latitude ($b=4.3^\circ$) quasar 2005$+$403, the second active galactic nuclei, in which we detected a rare phenomenon of multiple imaging induced by refractive-dominated scattering. The manifestation of this…

We carried out observations of pulsar PSR B1919+21 at 324 MHz to study the distribution of interstellar plasma in the direction of this pulsar. We used the RadioAstron (RA) space radiotelescope together with two ground telescopes:…

The interstellar scattering responsible for pulsar parabolic arcs, and for intra-day variability of compact radio quasars, is highly anisotropic in some cases. We numerically simulate these observed phenomena using totally anisotropic,…

Interstellar scintillations of pulsars PSR B0809+74 and B0950+08 have been studied using observations at low frequencies (41, 62, 89, and 112 MHz). Characteristic temporal and frequency scales of diffractive scintillations at these…

Scintillation arcs have become a powerful tool for exploring scattering in the ionized interstellar medium. There is accumulating evidence that the scattering from many pulsars is extremely anisotropic resulting in highly elongated, linear…

Context. The spatially coherent multipath propagation of pulsar radiation leads to a temporal and spectral interference patterns called scintillation. It is caused by density variations in the ionized interstellar medium, which often take…

Intensity scintillations of radio pulsars are known to originate from interference between waves scattered by the electron density irregularities of interstellar plasma, often leading to parabolic arcs in the two-dimensional power spectrum…

We present two years of monitoring observations of the extremely variable quasar J1819+3845. We observe large yearly changes in the timescale of the variations (from ~ 1 hour to ~ 10 hours at 5GHz). This annual effect can only be explained…