Related papers: Lofar, E-Lofar and Low-Frequency Vlbi

The radio astronomy community is currently building a number of phased array telescopes. The calibration of these telescopes is hampered by the fact that covariances of signals from closely spaced antennas are sensitive to noise coupling…

The nuclear starburst in the nearby galaxy M82 provides an excellent laboratory for understanding the physics of star formation. This galaxy has been extensively observed in the past, revealing tens of radio-bright compact objects embedded…

The new generation of low-frequency radio telescopes, such as the Low Frequency Array (LOFAR: a Square Kilometre Array-low pathfinder), provides advancements in our capability of probing Galactic magnetism through low-frequency polarimetry.…

Traditional radio telescopes use large, steel dishes to observe radio sources. The LOFAR radio telescope is different, and uses tens of thousands of fixed, non-movable antennas instead, a novel design that promises ground-breaking research…

We briefly consider some design aspects of aperture arrays for use in radio astronomy, particularly contrasting the performance of dense and sparse aperture arrays. Recent insights have emerged in the final design phase of LOFAR which…

The Very Large Array (VLA) Low-frequency Sky Survey (VLSS) has imaged 95% of the 3*pi sr of sky north of declination = -30 degrees at a frequency of 74 MHz (4 meter wavelength). The resolution is 80" (FWHM) throughout, and the typical RMS…

For low-frequency radio astronomy, software correlation and beamforming on general purpose hardware is a viable alternative to custom designed hardware. LOFAR, a new-generation radio telescope centered in the Netherlands with international…

This paper introduces a novel variability report generator developed for the Large Array Survey Telescope (LAST), a cost-effective multi-purpose telescope array conducting a wide survey of the variable sky in the visible-light spectrum.…

Space Very Long Baseline Interferometry is a radio astronomy technique distinguished by a record-high angular resolution reaching single-digit microseconds of arc. The paper provides a brief account of the history of developments of this…

In this paper we present the European Low Frequency Survey (ELFS), a project that will enable foregrounds-free measurements of primordial $B$-mode polarization to a level 10$^{-3}$ by measuring the Galactic and extra-Galactic emissions in…

The development of new phased array systems in radio astronomy, as the low frequency array (LOFAR) and the square kilometre array (SKA), formed of a large number of small and flexible elementary antennas, has led to significant challenges.…

The observation and imaging of hundreds or thousands of radio sources with the technique of very long baseline interferometry (VLBI) is a computationally intensive task. However, these surveys allow us to conduct statistical investigations…

Low radio frequency surveys are important for testing unified models of radio-loud quasars and radio galaxies. Intrinsically similar sources that are randomly oriented on the sky will have different projected linear sizes. Measuring the…

We revisit the "Cluster-Cluster" or multi-view Very-Long-Baseline-Interferometry (VLBI) technique from the perspective of its synergy with the multi-beam features inherent in the Australian Square Kilometer Array Pathfinder (ASKAP)and its…

The Global mm-VLBI Array (GMVA) is the highest angular resolution imaging interferometer currently available as a common user facility. It is capable of angular resolutions on the order of 40 microarcseconds. Currently 14 stations in the…

Multi-epoch radio-interferometric observations of young stellar objects can be used to measure their displacement over the celestial sphere with a level of precision that currently cannot be attained at any other wavelength. In particular,…

Planck is the third generation of mm-wave instruments designed for space observations of the cosmic microwave background (CMB) anisotropies within the new Cosmic Vision 2020 ESA Science Program. Planck will map the whole sky with…

The Caltech-Jodrell Bank very long baseline interferometry (VLBI) Surveys give detailed 5 GHz VLBI images of several hundred milliarcsecond (mas) radio sources, and the full width at half-maximum angular sizes of the corresponding compact…

Extension of radio interferometric baselines into space is inevitable if a diffraction-limited angular resolution defined by the Earth diameter at a given observing wavelength limits a pursuit of specific scientific goals. This was…

Aims. An efficient means of locating calibrator sources for International LOFAR is developed and used to determine the average density of usable calibrator sources on the sky for subarcsecond observations at 140 MHz. Methods. We used the…