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Context: Exoplanet science has made staggering progress in the last two decades, due to the relentless exploration of new detection methods and refinement of existing ones. Yet astrometry offers a unique and untapped potential of discovery…

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,…

Astrophysics · Physics 2008-04-28 Laurent Loinard , Rosa M. Torres , Amy J. Mioduszewski , Luis F. Rodriguez

Highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances, and at successively shorter wavelengths. Here, we present the first diffraction-limited images in visual light,…

Instrumentation and Methods for Astrophysics · Physics 2015-04-21 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

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…

Monitoring turbulence parameters is crucial in high-angular resolution astronomy for various purposes, such as optimising adaptive optics systems or fringe trackers. The former are present at most modern observatories and will remain…

Instrumentation and Methods for Astrophysics · Physics 2023-10-25 Nuno Morujão , Carlos Correia , Paulo Andrade , Julien Woillez , Paulo Garcia

With sub-microarcsecond angular accuracy, the \theia telescope will be capable of revealing the architectures of nearby exoplanetary systems down to the mass of Earth. This research addresses the challenges inherent in space astrometry…

Instrumentation and Methods for Astrophysics · Physics 2024-08-29 F. Malbet , M. Lizzana , F. Pancher , S. Soler , A. Léger , T. Lépine , G. A. Mamon , A. Sozzetti , A. Riva , D. Busonero , L. Labadie , P. -O. Lagage , R. Goullioud

Up to now, the completion of an ALMA interferometric observation is determined based on the achievement of a given shape and size of the synthesized beam and the noise RMS in the representative spectral range. This approach with respect to…

Instrumentation and Methods for Astrophysics · Physics 2020-12-17 Dirk Petry , María Díaz Trigo , Rüdiger Kneissl , Ignacio Toledo , Stefano Facchini

Radio interferometry is an observational technique used to study astrophysical phenomena. Data gathered by an interferometer requires substantial processing before astronomers can extract the scientific information from it. Data processing…

Instrumentation and Methods for Astrophysics · Physics 2024-12-24 Brian M. Kirk , Urvashi Rau , Ramyaa Ramyaa

Transient radio signals of astrophysical origin present an avenue for studying the dynamic universe. With the next generation of radio interferometers being planned and built, there is great potential for detecting and studying large…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Cathryn M. Trott , Randall B. Wayth , Jean-Pierre R. Macquart , Steven J. Tingay

Intensity interferometry permits very long optical baselines and the observation of sub-milliarcsecond structures. Using planned kilometric arrays of air Cherenkov telescopes at short wavelengths, intensity interferometry may increase the…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 Dainis Dravins , Hannes Jensen , Stephan LeBohec , Paul D. Nuñez

The maximum likelihood method is often used for parameter estimation in gravitational wave astronomy. Recently, an interesting approach was proposed by Vallisneri to evaluate the distributions of parameter estimation errors expected for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Naoki Seto , Koutarou Kyutoku

The correction of the influence of phase corrugation in the pupil plane is a fundamental issue in achieving high dynamic range imaging. In this paper, we investigate an instrumental setup which consists in applying interferometric…

Astrophysics · Physics 2008-11-26 S. Lacour , E. Thiébaut , G. Perrin

Calibration is a key step in the signal processing pipeline of any radio astronomical instrument. The required sky, ionospheric and instrumental models for this step can suffer from various kinds of incompleteness. In this paper we analyze…

Instrumentation and Methods for Astrophysics · Physics 2019-02-08 A. Mouri Sardarabadi , L. V. E. Koopmans

Energy consumption and hardware cost of signal digitization together with the management of the resulting data volume form serious issues for high-rate measurement systems with multiple sensors. Switching to binary sensing front-ends…

Instrumentation and Methods for Astrophysics · Physics 2019-07-16 Manuel S. Stein

The spatial-frequency coverage of a radio interferometer is increased by combining samples acquired at different times and observing frequencies. However, astrophysical sources often contain complicated spatial structure that varies within…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 U. Rau

I present in this paper a method to calibrate data obtained from optical and infrared interferometers. I show that correlated noises and errors need to be taken into account for a very good estimate of individual error bars but also when…

Astrophysics · Physics 2009-11-07 G. Perrin

Radio interferometry is a powerful technique that allows astronomers to create high-resolution images of astronomical objects. The distribution of radio telescopes in an interferometer is a critical factor that determines the resolution and…

Instrumentation and Methods for Astrophysics · Physics 2024-09-04 Elio Quiroga Rodriguez

Having an accurate calibration method is crucial for any scientific research done by a radio telescope. The next generation radio telescopes such as the Square Kilometre Array (SKA) will have a large number of receivers which will produce…

Instrumentation and Methods for Astrophysics · Physics 2018-04-03 Ahmad Mouri Sardarabadi , Alle-Jan van der Veen , Léon V. E. Koopmans

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

Astrophysics of Galaxies · Physics 2009-03-05 Laurent Loinard , Luis F. Rodriguez , Amy J. Mioduszewski

We have developed a multi-pixel beamformer technique, which can be used for enhancing the capabilities for studying pulsars using an interferometric array. Using the Giant Metrewave Radio Telescope (GMRT), we illustrate the application of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Jayanta Roy , Bhaswati Bhattacharyya , Yashwant Gupta