Related papers: High-precision Measurements of Ionospheric TEC Gra…
We have used a relatively long, contiguous VHF observation of a bright cosmic radio source (Cygnus A) with the Very Large Array (VLA) through the nighttime, midlatitude ionosphere to demonstrate the phenomena observable with this…
The results of a climatological study of ionospheric disturbances derived from observations of cosmic sources from the Very Large Array (VLA) Low-frequency Sky Survey (VLSS) are presented. We have used the ionospheric corrections applied to…
This paper presents a case study from a single, six-hour observing period to illustrate the application of techniques developed for interferometric radio telescopes to the spectral analysis of observations of ionospheric fluctuations with…
We present the results of a multi-scale analysis of TEC fluctuations using a roughly five-hour observation of the bright radio source Virgo A with the Very Large Array (VLA) at 74 MHz in its B configuration. Our analysis combines data…
Phase stability at low radio frequencies is severely impacted by ionospheric propagation delays. Radio interferometers such as the Giant Metrewave Radio Telescope (GMRT) are capable of detecting changes in the ionosphere's total electron…
The Naval Research Laboratory and the National Radio Astronomy Observatory completed implementation of a low frequency capability on the VLA at 73.8 MHz in 1998. This frequency band offers unprecedented sensitivity (~25 mJy/beam) and…
High resolution (~1 arcminute) astronomical imaging at low frequency (below 150 MHz) has only recently become practical with the development of new calibration algorithms for removing ionospheric distortions. In addition to opening a new…
Radio interferometers, which are designed to observe astrophysical objects in the universe, can also be used to study the Earth's ionosphere. Radio interferometers like the Giant Metrewave Radio Telescope (GMRT) detect variations in…
The Very Small Array (VSA) is a fourteen-element interferometer designed to study the cosmic microwave background on angular scales of 2.4 to 0.2 degrees (angular multipoles l = 150 to 1800). It operates at frequencies between 26 and 36…
The low-latitude ionosphere is a dynamic region with a wide range of disturbances in temporal and spatial scales. The Giant Metrewave Radio Telescope (GMRT) situated in the low-latitude region has demonstrated its ability to detect various…
Developing algorithms to search through data efficiently is a challenging part of searching for signs of technology beyond our solar system. We have built a digital signal processing system and computer cluster on the backend of the Karl G.…
We have used the Very Large Array(VLA) in C configuration to carry out a sensitive 20cm radio survey of regions of sky that have been surveyed in the Far Infra-Red over the wavelength range 5-200 microns with ISO as part of the European…
To continue the unparalleled success of the Very Large Array (VLA) for radio astronomy, the facility is currently being converted to become the 'Expanded VLA' (EVLA). The EVLA will radically improve the VLA in order to cover the full…
The Very Small Array (VSA) is a synthesis telescope designed to image faint structures in the cosmic microwave background on degree and sub-degree angular scales. The VSA has key differences from other CMB interferometers with the result…
Results derived from analysing the ionosphere response to faint and bright solar flares are presented. The analysis used technology of a global detection of ionospheric effects from solar flares as developed by the authors, on the basis of…
In almost 30 years of operation, the Very Large Array (VLA) has proved to be a remarkably flexible and productive radio telescope. However, the basic capabilities of the VLA have changed little since it was designed. A major expansion…
Low-frequency, wide field-of-view (FoV) radio telescopes such as the Murchison Widefield Array (MWA) enable the ionosphere to be sampled at high spatial completeness. We present the results of the first power spectrum analysis of…
The development of regional services able to provide ionospheric vertical totalelectron content (VTEC) maps and ionospheric indexes with a high spatialresolution, and in near-real-time, are of great importance for both civilianapplications…
We employed the Very Large Array (VLA) of the National Radio Astronomy Observatory in C configuration to map 39 ultraluminous IRAS galaxies at 6~cm and 20~cm, at resolutions of ~ 4" and 15", respectively, and 24 sources at 6~cm with in the…
The ionospheric scattering of pulses emitted by PSR B0950+08 is measured using the 10-m RadioAstron Space Radio Telescope, the 300-m Arecibo Radio Telescope and the 14x25-m Westerbork Synthesis Radio Telescope (WSRT) at a frequency band…