相关论文: Double-lens Scintillometry: The variable scintilla…

The pulsating hydrogen atmosphere white dwarf star G 117-B15A has been observed since 1974. Its main pulsation period at 215.19738823(63) s, observed in optical light curves, varies by only (5.12+/-0.82)x10^{-15} s/s and shows no glitches,…

We present observations that show dramatic evolution of the mean pulse profile of the relativistic binary pulsar J1141--6545 over a period of five years. This is consistent with precession of the pulsar spin axis due to relativistic…

Observations of pulsars across the radio spectrum are revealing a dependence of the characteristic scattering time ($\tau$) on frequency, which is more complex than the simple power law with a theoretically predicted power law index. In…

Context. The scattering polarization signal observed in the photospheric Sr i 4607 {\AA} line is expected to vary at granular spatial scales. This variation can be due to changes in the magnetic field intensity and orientation (Hanle…

We investigate the radio emission behaviour of PSR B0823+26, a pulsar which is known to undergo pulse nulling, using an 153-d intensive sequence of observations. The pulsar is found to exhibit both short (~min) and unusually long-term…

This study investigates the spatial and temporal characteristics of L1 amplitude scintillation-causing ionospheric irregularities over the Eastern Arabian Peninsula during the ascending phase of solar cycle 25 (years 2020--2023). The…

We present the results of precision timing observations of the binary millisecond pulsar PSR J1640+2224. Combining the pulse arrival time measurements made with the Effelsberg 100-m radio telescope and the Arecibo 305-m radio telescope, we…

PSR B0950+08 is a bright non-recycled pulsar whose single-pulse fluence variability is reportedly large. Based on observations at two widely separated frequencies, 55 MHz (NenuFAR) and 1.4 GHz (Westerbork Synthesis Radio Telescope), we…

We study the effect of pulsar rotation on timing of binary pulsars, with particular emphasis on the double pulsar system J0737-3039. Special relativistic aberration due to the orbital motion of pulsar changes both the longitude and…

We present an extended study of the Be/X-ray pulsar 2S 1553-542 during its Type II outbursts. We have incorporated \emph{NICER, Swift-XRT, RXTE-PCA, \emph{NuSTAR} and FERMI} observations to carry out the detailed phase and time resolved…

Humans will launch spacecraft that travel at an appreciable fraction of the speed of light. Spacecraft traffic will be tracked by radar. Scattering of pulsed electromagnetic fields by an object in uniform translational motion at…

Pulsar dynamic spectra exhibit high visibility fringes arising from interference between scattered radio waves. These fringes may be random or highly ordered patterns, depending on the nature of the scattering or refraction. Here we…

Despite some success in explaining the observed polarisation angle swing of radio pulsars within the geometric rotating vector model, many deviations from the expected S-like swing are observed. In this paper we provide a simple and…

Interstellar scattering causes broadening and distortion to the mean pulse profiles and polarization position angle (PPA) curves, especially to the pulse profiles observed at lower frequency. This paper has implemented a method to recover…

The behaviour of the pulsar spectrum at high radio frequencies can provide decisive information about the nature of the radio emission mechanism. We report recent observations of a selected sample of pulsars at lambda=9mm (32 GHz) with the…

We present a comparative study of the low-frequency eclipses of spider (compact, irradiating binary) PSRs B1957+20 and J1816+4510. Combining these data with those of three other eclipsing systems we study the frequency dependence of the…

We have measured the scatter broadening of pulsars in the direction of the Gum nebula. For the first time, our observations show clear variations of scattering properties across the Gum nebula. The IRAS-Vela shell is shown to be a high…

Giant pulses from Crab pulsar were observed together with Radioastron space radiotelescope, Global EVN radio telescopes and Kvazar-KVO VLBI stations to study the scattering effects in the ISM. Five observing sessions were conducted at 18 cm…

We investigate the possibilities that pulsars act as the lens in gravitational microlensing events towards the galactic bulge or a spiral arm. Our estimation is based on expectant survey and observations of FAST (Five hundred meter Aperture…

Fast Radio Bursts (FRBs) exhibit scintillation and scattering, often attributed to interactions with plasma screens in the Milky Way and the host galaxy. When these two screens appear "point-like" to each other, two scales of scintillation…