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Related papers: Radio Interferometers with wide bandwidths

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In this paper, we discuss the potential importance of measuring the CMB anisotropy bispectrum. We develop a formalism for computing the bispectrum and for measuring it from microwave background maps. As an example, we compute the bispectrum…

Astrophysics · Physics 2016-08-25 David N. Spergel , David M. Goldberg

While, in general, interferometers provide high spatial resolution for imaging small-scale structure (corresponding to high spatial frequencies in the Fourier plane), single-dishes can be used to image the largest spatial scales…

Astrophysics · Physics 2007-05-23 S. Stanimirovic

Radio interferometry most commonly involves antennas or antenna arrays of identical design. The identical antenna assumption leads to a convenient and useful mathematical simplification resulting in a scalar problem. An interesting variant…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Adrian T. Sutinjo , Daniel Ung , Tim M. Colegate , Randall B. Wayth , Peter J. Hall , Eloy de Lera Acedo

Radio astronomical observation below 30 MHz is hampered by the refraction and absorption of the ionosphere, and the radio frequency interference (RFI), so far high angular resolution sky intensity map is not available. An interferometer…

Instrumentation and Methods for Astrophysics · Physics 2018-07-09 Qizhi Huang , Shijie Sun , Shifan Zuo , Fengquan Wu , Yidong Xu , Bin Yue , Reza Ansari , Xuelei Chen

Accelerator mass spectrometry (AMS) is a widely-used technique with multiple applications, including geology, molecular biology and archeology. In order to achieve a high dynamic range, AMS requires tandem accelerators and large magnets,…

Quantum Physics · Physics 2023-05-23 Radu Ionicioiu

I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 T. D. Carozzi

The manipulation of light by conventional optical components such as a lenses, prisms and wave plates involves engineering of the wavefront as it propagates through an optically-thick medium. A new class of ultra-flat optical components…

We present a new method for interferometric imaging that is ideal for the large fields of view and compact arrays common in 21 cm cosmology. We first demonstrate the method with simulations for two very different low frequency…

Dynamic metasurface antennas (DMAs) represent a novel approach to programmable and affordable electromagnetic wave manipulation for enhanced wireless communications, sensing, and imaging applications. Nevertheless, current DMA designs and…

Signal Processing · Electrical Eng. & Systems 2025-10-24 Abdul Jabbar , Aakash Bansal , William Whittow

As Cosmic Microwave Background (CMB) measurements are becoming more ambitious, the issue of foreground contamination is becoming more pressing. This is especially true at the level of sensitivity, angular resolution and for the sky coverage…

Astrophysics · Physics 2009-10-31 François R. Bouchet , Richard Gispert

We describe an algorithm for the extraction of the angular power spectrum of an intensity field, such as the cosmic microwave background (CMB), from interferometer data. This new method, based on the gridding of interferometer visibilities…

Recently a symmetry-based method to test for statistical isotropy of the cosmic microwave background was developed. We apply the method to template-cleaned 3-year and 5-year WMAP-$DA$ maps. We examine a wide range of angular multipoles from…

Astrophysics · Physics 2010-11-02 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

Direction dependent calibration of widefield radio interferometers estimates the systematic errors along multiple directions in the sky. This is necessary because with most systematic errors that are caused by effects such as the ionosphere…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 Sarod Yatawatta

This paper introduces the Wide-band Asp-Clean (\texttt{WAsp}) algorithm, a novel scale-sensitive image reconstruction method tailored for wide-band imaging applications. This algorithm is particularly beneficial for thermal noise-limited…

Instrumentation and Methods for Astrophysics · Physics 2026-04-27 M. Hsieh , S. Bhatnagar , U. Rau

Calibration of instrumental polarization is critical for measuring polarized radio emissions from astrophysical sources to extract the magnetic field information in astrophysical, heliospheric, and terrestrial plasmas. At meter wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2025-05-08 Devojyoti Kansabanik , Angelos Vourlidas , Soham Dey , Surajit Mondal , Divya Oberoi

We investigate the imaging performance of an interferometric array in the case of wide field, high resolution, narrow band, snapshot imaging. We find that, when uv-cell sizes are sufficiently small (ie. image sizes are sufficiently large),…

Instrumentation and Methods for Astrophysics · Physics 2020-07-03 C. L. Carilli , E. Murphy , V. Rosero , K. Mooley , E. Jimenez-Andrade , K. Golap , B. Butler

Interferometric imaging is a well established method to image phase objects by mixing the image wavefront with a reference one on a CCD camera. It has also been applied to fast transient phenomena, mostly through the analysis of single…

We report on the design of an all-mirror wavefront-division interferometer capable of spectroscopic studies across multiple spectral ranges$\unicode{x2013}$from the plasma frequencies of metals to terahertz wavelengths and beyond. The…

Line intensity mapping experiments seek to trace large scale structure by measuring the spatial fluctuations in the combined emission, in some convenient spectral line, from individually unresolved galaxies. An important systematic concern…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-20 Adam Lidz , Jessie Taylor

Scattering of cosmic microwave background (CMB) radiation in galaxy clusters induces a polarization signal proportional to the CMB quadrupole anisotropy at the cluster's location and look-back time. A survey of such remote quadrupole…

Astrophysics · Physics 2007-05-23 Emory F. Bunn
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