English
Related papers

Related papers: 21 cm observations: calibration, strategies, obser…

200 papers

Our ability to calibrate current kilometer-scale interferometers can potentially confound the inference of astrophysical signals. Current calibration uncertainties are well described by a Gaussian process. I exploit this description to…

Instrumentation and Methods for Astrophysics · Physics 2022-04-27 Reed Essick

With ever increasing data rates produced by modern radio telescopes like LOFAR and future telescopes like the SKA, many data processing steps are overwhelmed by the amount of data that needs to be handled using limited compute resources.…

Instrumentation and Methods for Astrophysics · Physics 2020-03-18 Sarod Yatawatta

I present our analysis of the 21cm power spectrum upper limits from the HERA radio interferometer, published in HERA Collaboration et al. 2022. We use the recent limits to constrain reionization and the properties of the IGM and galaxies in…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-25 Stefan Heimersheim

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.…

This paper provides a general introduction to the problem of image reconstruction from interferometric data. A simple model of the interferometric observables is given and the issues arising from sparse Fourier data are discussed. The…

Instrumentation and Methods for Astrophysics · Physics 2017-08-29 Éric Thiébaut , John Young

Modern interferometers routinely provide radio-astronomical images down to subarcsecond resolution. However, interferometers filter out spatial scales larger than those sampled by the shortest baselines, which affects the measurement of…

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic clocks. Atom…

Quantum Physics · Physics 2009-08-03 Alexander D. Cronin , Joerg Schmiedmayer , David E. Pritchard

This paper serves as a reference on how to estimate the parameters of binary stars and how to combine multiple techniques, namely astrometry, interferometry and radial velocities.

Solar and Stellar Astrophysics · Physics 2015-10-29 Daniel Bonneau , Florentin Millour , Anthony Meilland

The paper proposes a novel calibration approach for the Orthoglide-type mechanisms based on observations of the manipulator leg parallelism during mo-tions between the prespecified test postures. It employs a low-cost measuring system…

Robotics · Computer Science 2007-11-13 Anatoly Pashkevich , Damien Chablat , Philippe Wenger

Polarimetric interferometry is a method allowing the study of the distribution of polarized flux at diffraction-limited resolution. Its basic observable is the ratio $\mathcal{R}$ of the visibilities of the object in two orthogonal…

Instrumentation and Methods for Astrophysics · Physics 2019-02-27 Boris Safonov , Pavel Lysenko , Maria Goliguzova , Dmitry Cheryasov

High fidelity radio interferometric data calibration that minimises spurious spectral structure in the calibrated data is essential in astrophysical applications, such as 21 cm cosmology, which rely on knowledge of the relative spectral…

Instrumentation and Methods for Astrophysics · Physics 2022-10-26 Peter H. Sims , Jonathan C. Pober , Jonathan L. Sievers

While optical and quantum efficiency are on the rise, and spectrographs becoming massively multiplexed, measuring spectral energy distributions of astronomical sources with accuracy remains a challenge. In addition to atmospheric…

Solar and Stellar Astrophysics · Physics 2019-03-19 Carlos Allende Prieto

Radio interferometers can measure the full polarization state of incoming waves by cross--correlating all combinations of two orthogonal polarizations at each antenna. The independent sets of electronics used to detect the two polarization…

Instrumentation and Methods for Astrophysics · Physics 2012-05-18 W. D. Cotton

We describe a laser interferometer experiment for the undergraduate teaching laboratory that achieves picometer sensitivity in a hands-on table-top instrument. In addition to providing an introduction to interferometer physics and optical…

Instrumentation and Detectors · Physics 2015-06-22 Kenneth G. Libbrecht , Eric D. Black

Latest-generation spectro-interferometric instruments combine a milliarcsecond angular resolution with spectral capabilities, resulting in an immensely increased information content. Here, I present methodological work and results that…

Instrumentation and Methods for Astrophysics · Physics 2013-12-17 Stefan Kraus

The optical interferometry has been widely used in various high precision applications. Usually, the minimum precision of an interferometry is limited by various technique noises in practice. To suppress such kind of noises, we propose a…

Optics · Physics 2018-06-20 Chen Fang , Jing-Zheng Huang , Guihua Zeng

We introduce CALAMITY, a precision bandpass calibration method for radio interferometry. CALAMITY can solve for direction independent gains with arbitrary frequency structure to the high precision required for 21 cm cosmology with minimal…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-01 Aaron Ewall-Wice , Joshua S. Dillon , Bharat Gehlot , Aaron Parsons , Tyler Cox , Daniel C. Jacobs

Paper I of the series re-derived the radio interferometry measurement equation (RIME) from first principles, and extended the Jones formalism to the full-sky case, incorporating direction-dependent effects (DDEs). This paper aims to…

Instrumentation and Methods for Astrophysics · Physics 2011-02-07 Oleg M. Smirnov

This chapter describes the astrophysics encoded by the 21-cm background. We begin with a brief introduction to the radiative transfer and ionization chemistry relevant to the high-z intergalactic medium. Then, we will provide a review of…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-30 Jordan Mirocha

X-ray interferometry has the potential to provide imaging at ultra high angular resolutions of 100 micro arc seconds or better. However, designing a practical interferometer which fits within a reasonable envelope and that has sufficient…

Astrophysics · Physics 2009-11-10 R. Willingale