Related papers: Interstellar scintillation is an indicator of astr…
PKS 1257-326 is a quasar showing extremely unusual, rapid interstellar scintillation (ISS), which has persisted for at least a decade. Simultaneous observations with the VLA and ATCA, combined with ATCA monitoring over several years, have…
We investigate the relationship between 5 GHz interstellar scintillation (ISS) and 15 GHz intrinsic variability of compact, radio-selected AGNs drawn from the Microarcsecond Scintillation-Induced Variability (MASIV) Survey and the Owens…
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…
Observations of pulsar scintillation are among the few astrophysical probes of very small-scale ($\lesssim$ au) phenomena in the interstellar medium (ISM). In particular, characterization of scintillation arcs, including their curvature and…
We present here the results from an extensive scintillation study of twenty pulsars in the dispersion measure (DM) range 3 - 35 pc cm^-3 caried out using the Ooty Radio Telescope (ORT) at 327 MHz, to investigate the distribution of ionized…
We report the first astrophysical application of the technique of wide-field Interplanetary Scintillation (IPS) with the Murchison Widefield Array (MWA). This powerful technique allows us to identify and measure sub-arcsecond compact…
We investigate the feasibility of detecting and probing various components of the ionized intergalactic medium (IGM) and their turbulent properties at radio frequencies through observations of scatter broadening of compact sources. There is…
The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along…
In this paper, we report our investigation of pulsar scintillation phenomena by monitoring PSR B0355$+$54 at 2.25 GHz for three successive months using \emph{Kunming 40-m radio telescope}. We have measured the dynamic spectrum, the…
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…
This paper presents an investigation into the gravitational microlensing of quasars by stars and stellar remnants in the Milky Way. We present predictions for the all-sky microlensing optical depth, time-scale distributions and event rates…
We demonstrate the linearity and stability of a gamma-ray scintillation detector comprised of a NaI(Tl) crystal and a scientific-grade CMOS camera. After calibration, this detector exhibits excellent linearity more than three decades of…
From 1979--1996 the Green Bank Interferometer was used by the Naval Research Laboratory to monitor the flux density from 146 compact radio sources at frequencies near 2 and 8 GHz. We filter the ``light curves'' to separate intrinsic…
Scintillation noise due to the Earth's turbulent atmosphere can be a dominant noise source in high-precision astronomical photometry when observing bright targets from the ground. Here we describe the phenomenon of scintillation from its…
The concordance model of cosmology favours a universe with a tiny positive cosmological constant. A tiniest positive constant curvature, profoundly alters the asymptotic structure, forcing a re-look at a theory of gravitational radiation.…
We study three quasar radio sources (B1257-326, B1519-273, and J1819+385) that show large amplitude intraday and annual scintillation variability produced by the Earth's motion relative to turbulent-scattering screens located within a few…
This paper explores the viability and stability of compact stellar objects characterized by anisotropic matter in the framework of $f(\mathrm{Q},\mathrm{T})$ theory, where $\mathrm{Q}$ denotes non-metricity and $\mathrm{T}$ represents the…
We describe measurements of the size of the Vela pulsar via scintillation, using both fits to the distribution of intensity and measurements of the modulation index. We briefly discuss systematic effects other than source size that can…
The structural stability of a lightsail under the laser flux necessary for interstellar flight is studied analytically and numerically. A sinusoidal perturbation is introduced into a two-dimensional thin-film sail to determine if the sail…
The recent observations of neutron star mergers have changed our perspective on scalar- tensor theories of gravity, favouring models where gravitational waves travel at the speed of light. In this work we consider a scalar-tensor set-up…