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Related papers: Contaminants in ATCA baselines with shadowing: a c…

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Image plane beam combination in optical interferometers multiplexes the interference fringes from multiple baselines onto a single detector. The beams of starlight are arranged in a non-redundant pattern at the entrance of the combiner so…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 Daniel J. Mortimer , David F. Buscher

Radio interferometer arrays such as HERA consist of many close-packed dishes arranged in a regular pattern, giving rise to a large number of `redundant' baselines with the same length and orientation. Since identical baselines should see an…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Samir Choudhuri , Philip Bull , Hugh Garsden

We derive a general formalism for interferometric visibilities, which considers first-order antenna-antenna coupling and assumes steady-state, incident radiation. We simulate such coupling features for non-polarized skies on a compact,…

Instrumentation and Methods for Astrophysics · Physics 2022-04-06 Alec T. Josaitis , Aaron Ewall-Wice , Nicolas Fagnoni , Eloy de Lera Acedo

We study how coherent scattering of a background gas off an atom (or other matter) interferometer can lead to enhanced signals from phase shifts and contrast loss. We focus on the inclusion of realistic features of atom interferometers such…

High Energy Physics - Phenomenology · Physics 2025-09-18 Clara Murgui , Ryan Plestid

We present an approach to building interferometric telescopes using ideas of quantum information. Current optical interferometers have limited baseline lengths, and thus limited resolution, because of noise and loss of signal due to the…

Quantum Physics · Physics 2012-09-03 Daniel Gottesman , Thomas Jennewein , Sarah Croke

Australia Telescope Compact Array (ATCA) observations in sky regions selected to be low in foreground confusion have been used to infer limits on arcmin-scale CMB anisotropy in total intensity and polarization. These deep searches have,…

Astrophysics · Physics 2007-05-23 Ravi Subrahmanyan

In long-baseline interferometry, bandwidth smearing of an extended source occurs at finite bandwidth when its different components produce interference packets that only partially overlap. In this case, traditional model fitting or image…

Instrumentation and Methods for Astrophysics · Physics 2013-08-07 Régis Lachaume , Jean-Philippe Berger

A new astronomical window into the southern skies has been opened with the high-frequency upgrade to the Australia Telescope Compact Array (ATCA), which allows radio-interferometric mapping of sources at wavelengths as short as 3mm. In…

Astrophysics · Physics 2009-11-07 T. Wong , A. Melatos

The Australia Telescope Compact Array and the Very Large Array are currently being upgraded to operate with wide bandwidths; interferometers dedicated to the measurement of cosmic microwave background anisotropies are being designed with…

Astrophysics · Physics 2009-11-10 Ravi Subrahmanyan

Infrared interferometers are optical devices that can measure optical path-length differences by measuring changes in the refractive index. Several arrangements can be deployed, from single channel devices to multichannel double color…

Signal Processing · Electrical Eng. & Systems 2024-02-16 Luis Esteban , Alberto Regadío , Ulises Losada

We study the behavior of internal signal chain reflections and antenna cross coupling as systematics for 21 cm cosmological surveys. We outline the mathematics for how these systematics appear in interferometric visibilities and describe…

Instrumentation and Methods for Astrophysics · Physics 2019-10-28 Nicholas S. Kern , Aaron R. Parsons , Joshua S. Dillon , Adam E. Lanman , Nicolas Fagnoni , Eloy de Lera Acedo

The interference between resonance signal and continuum background can be either constructive or destructive, depending on the relative sign of couplings between the signal and background amplitudes. Different interference schemes lead to…

High Energy Physics - Phenomenology · Physics 2016-05-13 Ligong Bian , Da Liu , Jing Shu , Yongchao Zhang

We introduce a simple theoretical model that describes the interaction of light with optical metamaterials in terms of interfering optical plane waves. In this model, a metamaterial is considered to consist of planar arrays of densely…

Optics · Physics 2013-11-25 P. Grahn , A. Shevchenko , M. Kaivola

Radio telescopes are susceptible to interference arriving through its sidelobes. If a reflector antenna could be retrofitted with an adaptive null steering system, it could potentially mitigate this interference. The design of a…

Systems and Control · Electrical Eng. & Systems 2024-01-01 Jordan Budhu , Sean V. Hum , Steven Ellingson , R. Michael Buehrer

We summarise the mathematical foundation of the holographic method of measuring the reflector profile of an antenna or radio telescope. In particular, we treat the case, where the signal source is located at a finite distance from the…

Astrophysics · Physics 2016-11-18 J. W. M. Baars , R. Lucas , J. G. Mangum , J. A. Lopez-Perez

We report the use of the Australia Telescope Compact Array (ATCA) to conduct polarimetric observations of the sky at 5 GHz. The ATCA is normally operated as an interferometer array, but these observations were conducted in a split array…

Astrophysics · Physics 2010-11-11 D. McConnell , E. Carretti , R. Subrahmanyan

Interpixel capacitance (IPC) between adjacent pixels in hybridized arrays gives rise to an electrostatic cross talk. This cross talk causes MTF degradation and blurring of images or spectra collected using these devices. As pixel size is…

Instrumentation and Methods for Astrophysics · Physics 2019-12-19 Kevan Donlon , Zoran Ninkov , Stefi Baum

Context: Fourier transform (or lag) correlators in radio interferometers can serve as an efficient means of synthesising spectral channels. However aliasing corrupts the edge channels so they usually have to be excluded from the data set.…

Astrophysics · Physics 2009-11-13 Tak Kaneko , Keith Grainge

Cross-talk is a well-known feature of single-photon avalanche detectors. It is especially important to account for this effect in applications involving coincidences of two or more photons registered by the sensor since in this case the…

Radio interferometers consisting of identical antennas arranged on a regular lattice permit fast Fourier transform beamforming, which reduces the correlation cost from $\mathcal{O}(n^2)$ in the number of antennas to $\mathcal{O}(n\log n)$.…

Instrumentation and Methods for Astrophysics · Physics 2019-05-20 Kiyoshi W. Masui , J. Richard Shaw , Cherry Ng , Kendrick M. Smith , Keith Vanderlinde , Adiv Paradise
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