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Related papers: Space VLBI at Low Frequencies

200 papers

A crucial part of a space mission for very-long baseline interferometery (VLBI), which is the technique capable of providing the highest resolution images in astronomy, is orbit determination of the mission's space radio telescope(s). In…

Aims: This paper discusses the spectral occupancy for performing radio astronomy with the Low-Frequency Array (LOFAR), with a focus on imaging observations. Methods: We have analysed the radio-frequency interference (RFI) situation in two…

FarView is a proposed low frequency radio interferometer for deployment on the lunar far side, enabled by the Moon's radio quiet environment. Operating over 1-50 MHz inaccessible from Earth, FarView will open a new observational window and…

We discuss a technique for mapping the synchrotron turnover frequency distribution using nearly simultaneous, multi--frequency VLBI observations. The limitations of the technique arising from limited spatial sampling and frequency coverage…

Astrophysics · Physics 2009-10-30 A. P. Lobanov

Infrared and radio observations of the Epoch of Reionization promise to revolutionize our understanding of the cosmic dawn, and major efforts with the JWST, MWA and HERA are underway. While measurements of the ionizing sources with infrared…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Adam P. Beardsley , Miguel F. Morales , Adam Lidz , Matthew Malloy , Paul M. Sutter

To increase the number of sources with Very Long Baseline Interferometry (VLBI) astrometry available for comparison with the Gaia results, we have observed 31 young stars with recently reported radio emission. These stars are all in the…

Solar and Stellar Astrophysics · Physics 2024-06-12 Sergio A. Dzib , Laurent Loinard , Ralf Launhardt , Jazmín Ordóñez-Toro

The existing high technology laser-beam detectors of gravitational waves may find very useful applications in an unexpected area - geophysics. To make possible the detection of weak gravitational waves in the region of high frequencies of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 L. P. Grishchuk , V. V. Kulagin , V. N. Rudenko , A. Serdobolski

Pulsars can be used to search for stochastic backgrounds of gravitational waves of cosmological origin within the very low frequency band (VLF), $10^{-7}$ to $10^{-9}$ Hz. We propose to construct a special 50 m radio telescope. Regular…

Astrophysics · Physics 2008-11-26 Shou-Guan Wang , Zong-Hong Zhu , Zhen-Long Zou , Yuan-Zhong Zhang

Pulsars are the only cosmic radio sources known to be sufficiently compact to show diffractive interstellar scintillations. Images of the variance of radio signals in both time and frequency can be used to detect pulsars in large-scale…

Instrumentation and Methods for Astrophysics · Physics 2016-08-17 S. Dai , S. Johnston , M. E. Bell , W. A. Coles , G. Hobbs , R. D. Ekers , E. Lenc

In radio astronomy, the Ultra-Long Wavelengths (ULW) regime of longer than 10 m (frequencies below 30 MHz), remains the last virtually unexplored window of the celestial electromagnetic spectrum. The strength of the science case for…

Instrumentation and Methods for Astrophysics · Physics 2018-02-23 Linjie Chen , Amin Aminaei , Leonid I. Gurvits , Marc Klein Wolt , Hamid Reza Pourshaghaghi , Yihua Yan , Heino Falcke

Nowadays, compact sources like surfaces of nearby stars, circumstellar environments of stars from early stages to the most evolved ones and surroundings of active galactic nuclei can be investigated at milli-arcsecond scales only with the…

The arrival of the Square Kilometer Array (SKA) will revitalise all aspects of Very Long Baseline Interferometry (VLBI) astronomy at the lower frequencies. In the last decade there have been huge strides towards routinely achieving high…

Instrumentation and Methods for Astrophysics · Physics 2017-02-15 Maria J. Rioja , Richard Dodson , Gabor Orosz , Hiroshi Imai , Sandor Frey

Radio spectroscopy provides a unique inspection perspective for solar and space weather research, which can reveal the plasma and energetic electron information in the solar corona and inner heliosphere. However, Radio-Frequency…

Solar and Stellar Astrophysics · Physics 2023-02-22 Peijin Zhang , André R. Offringa , Pietro Zucca , Kamen Kozarev , Mattia Mancini

AIMS: To demonstrate and test the capability of the next generation of low-frequency radio telescopes to perform high resolution observations across intra-continental baselines. Jupiter's strong burst emission is used to perform broadband…

Astrophysics · Physics 2008-09-17 A. Nigl , P. Zarka , J. Kuijpers , H. Falcke , L. Baehren , L. Denis

Ground-based radio telescopes are routinely used to search for light dark matter (DM) candidates such as axion-like particles or dark photons. These instruments face however inherent limitations to push the searches to masses below…

High Energy Physics - Phenomenology · Physics 2026-05-19 Ruben Zatini , Francesca Calore , Pasquale Dario Serpico

Millimter (mm) frequencies are primarily sensitive to thermal emission from layers across the stellar chromosphere up to the transition region, while metrewave (radio) frequencies probe the coronal heights. Together the mm and radio band…

Solar and Stellar Astrophysics · Physics 2025-10-16 Atul Mohan

This chapter introduces the concepts of polarimetry in the case of low frequency radio astronomy. In this regime radio waves are usually not the signature of atomic or molecular transitions lines, but rather that of unstable particle…

Instrumentation and Methods for Astrophysics · Physics 2019-01-14 Baptiste Cecconi

Until recently, VLBI targets have been drawn almost exclusively from the brightest and most compact radio sources in the sky, with typical flux densities well in excess of a few tens of mJy. These sources are predominantly identified with…

Astrophysics · Physics 2007-05-23 M. A. Garrett

Traditionally VLBI observations focus on a small patch of sky and image typically a few 100 mas around a bright source, which is often used to self-calibrate the data. High spectral and time resolution is needed to image a larger area, in…

Due to the recent dramatic technological advances, infrared interferometry can now be applied to new classes of objects, resulting in exciting new science prospects, for instance, in the area of high-mass star formation. Although…

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