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Low frequency imaging radio arrays such as MWA, LWA and LOFAR have been recently commissioned, and significantly more advanced and flexible arrays are planned for the near term. These powerful instruments offer new opportunities for direct…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 C. Lonsdale , L. Benkevitch , I. Cairns , M. Crowley , P. Erickson , M. Knapp , K. Kozarev , F. Lind , P. McCauley , J. Morgan , D. Oberoi

The Allen Telescope Array (ATA) is a Large-Number-Small-Diameter radio telescope array currently with 42 individual antennas and 5 independent back-end science systems (2 imaging FX correlators and 3 time domain beam formers) located at the…

Aims. As part of the ongoing GRAVITY+ upgrade of the Very Large Telescope Interferometer infrastructure, we aim to improve the performance of the GRAVITY Fringe-Tracker, and to enable its use by other instruments. Methods. We modify the…

The ambitious scientific goals of the SKA require a matching capability for calibration of atmospheric propagation errors, which contaminate the observed signals. We demonstrate a scheme for correcting the direction-dependent ionospheric…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 Maria Rioja , Richard Dodson , Thomas Franzen

The Cherenkov Telescope Array (CTA) will be the next generation of ground-based instrument for Very High Energy gamma-ray astronomy. It will improve the sensitivity of current telescopes by up to an order of magnitude and provide energy…

Instrumentation and Methods for Astrophysics · Physics 2017-09-04 P. Cumani , T. Hassan , L. Arrabito , K. Bernlöhr , J. Bregeon , G. Maier , A. Moralejo

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…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. S. Cohen , H. J. A. Röttgering

We discuss absolute calibration strategies for Phase I of the Hydrogen Epoch of Reionization Array (HERA), which aims to measure the cosmological 21 cm signal from the Epoch of Reionization (EoR). HERA is a drift-scan array with a 10 degree…

The Hubble constant value is currently known to 10% accuracy unless assumptions are made for the cosmology (Sandage et al. 2006). Gravitational lens systems provide another probe of the Hubble constant using time delay measurements.…

Instrumentation and Methods for Astrophysics · Physics 2010-12-01 G. Gürkan , N. Jackson , I. W. A. Browne , L. V. E. Koopmans , C. D. Fassnacht , A. Berciano Alba

This paper investigates how near-field beamfocusing can be achieved using a modular linear array (MLA), composed of multiple widely spaced uniform linear arrays (ULAs). The MLA architecture extends the aperture length of a standard ULA…

Signal Processing · Electrical Eng. & Systems 2025-12-09 Alva Kosasih , Özlem Tuğfe Demir , Emil Björnson

In the near future, the Expanded Very Large Array (EVLA) will allow surveys for maser sources with unprecedented sensitivity, spectral coverage and spectroscopic capabilities. In particular, comprehensive surveys for many maser species with…

Astrophysics · Physics 2009-11-13 Karl M. Menten

High-precision interferometric measurements of pulsating stars help to characterize their close environment. In 1974, a close companion was discovered around the pulsating star beta Cep using the speckle interferometry technique and…

The next-generation Very Large Array (ngVLA) is intended to be the premier centimeter-wavelength facility for astronomy and astrophysics, building on the substantial scientific legacies of the Karl G. Jansky Very Large Array (VLA) and the…

The signal processing community currently witnesses the emergence of sensor array processing and Direction-of-Arrival (DoA) estimation in various modern applications, such as automotive radar, mobile user and millimeter wave indoor…

Signal Processing · Electrical Eng. & Systems 2024-10-28 Marius Pesavento , Minh Trinh-Hoang , Mats Viberg

The aimed high sensitivities and large fields of view of the new generation of interferometers impose to reach high dynamic range of order $\sim$1:$10^6$ to 1:$10^8$ in the case of the Square Kilometer Array. The main problem is the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 C. Tasse , B. van der Tol , J. van Zwieten , Ger van Diepen , S. Bhatnagar

Global 21-cm experiments require exquisitely precise calibration of the measurement systems in order to separate the weak 21-cm signal from Galactic and extragalactic foregrounds as well as instrumental systematics. Hitherto, experiments…

Instrumentation and Methods for Astrophysics · Physics 2022-04-27 Jishnu N. Thekkeppattu , Benjamin McKinley , Cathryn M. Trott , Jake Jones , Daniel C. X. Ung

New generation of radio interferometers are envisaged to produce high quality, high dynamic range Stokes images of the observed sky from the corresponding under-sampled Fourier domain measurements. In practice, these measurements are…

Instrumentation and Methods for Astrophysics · Physics 2020-01-08 Jasleen Birdi , Audrey Repetti , Yves Wiaux

Context. The performance of interferometers has largely been increased over the last ten years. But the number of observable objects is still limited due to the low sensitivity and imaging capability of the current facilities. Studies have…

Instrumentation and Methods for Astrophysics · Physics 2015-01-14 H. Le Coroller , J. Dejonghe , F. Hespeels , L. Arnold , T. Andersen , P. Deram , D. Ricci , P. Berio , A. Blazit , J-M. Clausse , C. Guillaume , J-P. Meunier , X. Regal , R. Sottile

We present a new technique based on fixed-delay interferometry for high throughput, high precision and multi-object Doppler radial velocity (RV) surveys for extra-solar planets. The Doppler measurements are conducted through monitoring the…

Astrophysics · Physics 2016-08-30 Jian Ge

Kilometric-scale optical imagers seem feasible to realize by intensity interferometry, using telescopes primarily erected for measuring Cherenkov light induced by gamma rays. Planned arrays envision 50--100 telescopes, distributed over some…

Instrumentation and Methods for Astrophysics · Physics 2010-09-30 Hannes Jensen , Dainis Dravins , Stephan LeBohec , Paul D. Nuñez

Atacama Large Millimeter/submillimeter Array (ALMA) will be the world largest mm/submm interferometer, and currently the Early Science is ongoing, together with the commissioning and science verification (CSV). Here we present a study of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 S. Matsushita , K. -I. Morita , D. Barkats , R. E. Hills , E. Fomalont , B. Nikolic