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Related papers: Primary Beam Shape Calibration from Mosaicked, Int…

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We present the first full release of a survey of the 150 MHz radio sky, observed with the Giant Metrewave Radio Telescope between April 2010 and March 2012 as part of the TGSS project. Aimed at producing a reliable compact source survey,…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-08 H. T. Intema , P. Jagannathan , K. P. Mooley , D. A. Frail

Detection of the fluctuations in 21 cm line emission from neutral hydrogen during the Epoch of Reionization in thousand hour integrations poses stringent requirements on calibration and image quality, both of which necessitate accurate…

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

This paper presents the effects of radio frequency interference (RFI) mitigation on a radio telescope's sensitivity and beam pattern. It specifically explores the impact of subspace-projection mitigation on the phased array feed (PAF) beams…

Instrumentation and Methods for Astrophysics · Physics 2024-05-28 Liroy Lourenco , Aaron P Chippendale

This paper is concerned with the channel estimation problem in millimetre wave (MMW) wireless systems with large antenna arrays. By exploiting the sparse nature of the MMW channel, we present an efficient estimation algorithm based on a…

Information Theory · Computer Science 2018-04-19 Matthew Kokshoorn , Peng Wang , Yonghui Li , Branka Vucetic

The Murchison Widefield Array (MWA) is a low-frequency aperture array capable of high-time and frequency resolution astronomy applications such as pulsar studies. The large field-of-view of the MWA (hundreds of square degrees) can also be…

Instrumentation and Methods for Astrophysics · Physics 2022-05-18 N. A. Swainston , N. D. R. Bhat , I. S. Morrison , S. J. McSweeney , S. M. Ord , S. E. Tremblay , M. Sokolowski

A main science goal for the Large Synoptic Survey Telescope (LSST) is to measure the cosmic shear signal from weak lensing to extreme accuracy. One difficulty, however, is that with the short exposure time ($\simeq$15 seconds) proposed, the…

Interferometry is a powerful technique for making sensitive, high-fidelity images of the sky, but is limited in its ability to measure extended or diffuse emission. Better images of extended astronomical objects can be obtained by…

Instrumentation and Methods for Astrophysics · Physics 2020-06-12 Brian S. Mason

The Atacama Large Millimeter/submillimeter Array remains the largest mm radio interferometer observatory world-wide. It is now conducting its 11th observing cycle. In our previous paper presented at this conference series in 2020, we…

Instrumentation and Methods for Astrophysics · Physics 2024-08-09 Dirk Petry , María Díaz Trigo , Rüdiger Kneissl , Ignacio Toledo , Atsushi Miyazaki , Toshinobu Takagi , Ashley Barnes , Francesca Bonanomi

Calibrating for direction-dependent ionospheric distortions in visibility data is one of the main technical challenges that must be overcome to advance low-frequency radio astronomy. In this paper, we propose a novel probabilistic,…

Instrumentation and Methods for Astrophysics · Physics 2020-01-15 J. G. Albert , M. S. S. L. Oei , R. J. van Weeren , H. T. Intema , H. J. A. Röttgering

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

The utilization of a 6.5m monolithic primary mirror in a compact three-mirror anastigmat (TMA) telescope design offers unprecedented capabilities to accommodate various next generation science instruments. This design enables the rapid and…

Instrumentation and Methods for Astrophysics · Physics 2023-09-12 Daewook Kim , Heejoo Choi , Ewan S. Douglas

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

Context. Phased Array Feeds (PAFs) are multi element receivers in the focal plane of a telescope that make it possible to form simultaneously multiple beams on the sky by combining the complex gains of the individual antenna elements.…

ALMA's high-resolution images allow to resolve the filamentary structure of the ISM down to few thousand au at kpc distances. We aim to systematically quantify the impact of the interferometric response and the effects of the short-spacing…

Astrophysics of Galaxies · Physics 2024-08-07 F. Bonanomi , A. Hacar , A. Socci , D. Petry , S. Suri

Motivated by the necessity of a high-quality stray light control in the detection of the gravitational waves in space, the spot size of a flat top beam generated by the clipping of the Gaussian beam (GB) is studied. By adopting the mode…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Zhen-Xiang Hao , Tim Haase , Hong-Bo Jin , Ya-Zheng Tao , Gudrun Wanner , Ruo-Xi Wu , Yue-Liang Wu

This paper proposes a bidirectional multibeam hybrid transmitarray (HTA) employing a transmission polarization-rotating metasurface (TPRM). A novel configuration is introduced to facilitate bidirectional beam scanning by combining the…

Systems and Control · Electrical Eng. & Systems 2024-08-05 Fan Qin , Yifei Liu , Chao Gu , Linfeng Zeng , Wenchi Cheng , Hailin Zhang , Steven Gao

The Physics of the Accelerating Universe (PAU) camera is an optical narrow band and broad band imaging instrument mounted at the prime focus of the William Herschel Telescope. We describe the image calibration procedure of the PAU Survey…

We present a new approach for image reconstruction and weak lensing measurements with interferometers. Based on the shapelet formalism presented in Refregier (2001), object images are decomposed into orthonormal Hermite basis functions. The…

Astrophysics · Physics 2009-11-06 Tzu-Ching Chang , Alexandre Refregier

Knowledge of the beam profiles is of critical importance for interpreting data from cosmic microwave background experiments. In this paper, we present the characterization of the in-flight optical response of the WMAP satellite. The main…

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