Results 81 to 90 of about 736 (212)

Plasma Lensing Modeling of Substructures on Pulsar Scintillation Screens

The Astronomical Journal
Radio pulsars, as highly coherent point sources, serve as powerful probes of the ionized interstellar medium (IISM). Pulsar scintillation observations have revealed inverted arclets on the secondary spectrum, indicating quasilinearly aligned images ...
Zhu Xu, Xun Shi
doaj   +1 more source

Refractive interstellar scintillation in pulsar dynamic spectra [PDF]

, 1994
The evolution of the dynamic spectra of eight pulsars over 16 months is reported. Observations were made at Jodrell Bank at 408 MHz from 1984 September to 1986 January.
Lyne, A. G., Gupta, Y., Rickett, B. J.
core   +2 more sources

Stokes Phenomena in Lensing

The Astrophysical Journal
As lensing of coherent astrophysical sources, e.g., pulsars, fast radio bursts, and gravitational waves, becomes observationally relevant, the mathematical framework of Picard–Lefschetz theory has recently been introduced to fully account for wave optics
Xun Shi
doaj   +1 more source

Scintillation of the First-known Pulsar Planetary System

The Astrophysical Journal
We present a scintillation study of the first-known pulsar planetary system, PSR B1257+12, using the Five-hundred-meter Aperture Spherical radio Telescope. A total of 31 observations with durations greater than or equal to 30 minutes were analyzed.
J. M. Yao, L. Zhang, A. Wolszczan, William A. Coles, D. Li, Richard N. Manchester, N. Wang, C. H. Niu, P. Wang, F. F. Kou, J. P. Yuan   +10 more
doaj   +1 more source

Radio variability and interstellar scintillation of blazars [PDF]

, 2003
This thesis presents several observational studies based on radio variability and interstellar scintillation of extragalactic flat-spectrum radio sources.
Bignall, Hayley Emma
core  

A Simultaneous Dual-frequency Scintillation Arc Survey of Six Bright Canonical Pulsars Using the Upgraded Giant Metrewave Radio Telescope

The Astrophysical Journal
We use the upgraded Giant Metrewave Radio Telescope (uGMRT) to measure scintillation arc properties in six bright canonical pulsars with simultaneous dual-frequency coverage.
Jacob E. Turner, Bhal Chandra Joshi, Maura A. McLaughlin, Daniel R. Stinebring   +3 more
doaj   +1 more source

Lensing Point-spread Function of Coherent Astrophysical Sources and Nontrivial Wave Effects

The Astrophysical Journal
Most research on astrophysical lensing has been conducted using the geometric optics framework, where there exists a clear concept of lensing images. However, wave optics effects can be important for coherent sources, e.g., pulsars, fast radio bursts ...
Xun Shi
doaj   +1 more source

Interstellar scintillation of extragalactic radio sources

The Astrophysical Journal, 1975
Observations of 12 compact extragalactic sources were made at 2695 and 8085 MHz in order to detect weak intensity fluctuations caused by interstellar scintillation. Pulsar data are used to estimate the parameters of the interstellar medium needed to interpret the measured upper limits in terms of source angular diameters which are much larger than the
J. J. Condon, D. C. Backer
openaire   +1 more source

A Direct Measurement of the Electron Density Turbulence Parameter C1 and Implications for the Emission Size of Magnetar XTE J1810-197

The Astrophysical Journal Letters
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.
Visweshwar Ram Marthi, Yogesh Maan
doaj   +1 more source

Pulsar Scattering as a Probe for Structures in the Interstellar Medium

The Astrophysical Journal
Due to the inhomogeneity of electron number density, radio waves emitted by pulsars undergo scattering as they pass through the interstellar medium (ISM).
Qiuyi He, Xun Shi, Guangxing Li
doaj   +1 more source