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Related papers: MWA Tied-Array Processing I: Calibration and Beamf…

200 papers

We present new molecular modelling for 14NO and 15NO and a deep, blind molecular line survey at low radio frequencies (99-129 MHz). This survey is the third in a series completed with the Murchison Widefield Array (MWA), but in comparison…

Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Jonathan Landon , Michael Elmer , Jacob Waldron , David Jones , Alan Stemmons , Brian D. Jeffs , Karl F. Warnick , J. Richard Fisher , Roger D. Norrod

Diffuse, non-thermal emission in galaxy clusters is increasingly being detected in low-frequency radio surveys and images. We present a new diffuse, steep-spectrum, non-thermal radio source within the cluster Abell 1127 found in survey data…

Astrophysics of Galaxies · Physics 2020-07-31 Stefan W. Duchesne , Melanie Johnston-Hollitt , Zhenghao Zhu , Randall B. Wayth , Jack L. B. Line

We present a targeted search for low-frequency (144--215\,MHz) FRB emission from five repeating FRBs using 23.3\,hr of archival data taken with the Murchison Widefield Array (MWA) Voltage Capture System (VCS) between 2014 September and 2020…

High Energy Astrophysical Phenomena · Physics 2022-11-30 J. Tian , G. E. Anderson , P. J. Hancock , J. C. A. Miller-Jones , M. Sokolowski , C. W. James , N. D. R. Bhat , N. A. Swainston , D. Ung , B. W. Meyers

In millimeter-wave communications (MMWC), in order to compensate for high propagation attenuation, phased arrays are favored to achieve array gain by beamforming, where transmitting and receiving antenna arrays need to be jointly trained to…

Information Theory · Computer Science 2016-11-15 Zhenyu Xiao , Lin Bai , Jinho Choi

We describe an on-sky demonstration of a microwave-multiplexing readout system in one of the receivers of the Keck Array, a polarimetry experiment observing the cosmic microwave background at the South Pole. During the austral summer of…

Aperture array (AA) technology is at the forefront of new developments and discoveries in radio astronomy. Currently LOFAR is successfully demonstrating the capabilities of dense and sparse AA's at low frequencies. For the mid-frequencies,…

Instrumentation and Methods for Astrophysics · Physics 2012-09-21 Ilse M. van Bemmel , Arnold van Ardenne , Jan Geralt bij de Vaate , Andrew J. Faulkner , Raffaella Morganti

We test the bandpass smoothness performance of two prototype Square Kilometre Array (SKA) SKA1-Low log-periodic dipole antennas, the SKALA2 and SKALA3 (`SKA Log-periodic Antenna'), and the current dipole from the Murchison Widefield Array…

Instrumentation and Methods for Astrophysics · Physics 2017-06-28 Cathryn M. Trott , Eloy de Lera Acedo , Randall B. Wayth , Nicolas Fagnoni , Adrian T. Sutinjo , Brett Wakley , Chris Ivan B. Punzalan

Sensitive radio instruments are optimized for observing faint astronomical sources, and usually need to attenuate the received signal when observing the Sun. There are only a handful of flux density calibrators which can comfortably be…

Solar and Stellar Astrophysics · Physics 2022-03-03 Devojyoti Kansabanik , Surajit Mondal , Divya Oberoi , Ayan Biswas , Shilpi Bhunia

The Multipurpose Interferometer Array Pathfinder (MIA), developed from the Argentine Institute of Radio Astronomy (IAR), is a radio astronomical instrument based on interferometry techniques, designed for the detection of radio emission…

Instrumentation and Methods for Astrophysics · Physics 2023-12-29 J. M. Gonzalez , H. Command , G. Valdez

Acoustic beamforming with a microphone array represents an adequate technology for remote acoustic surveillance, as the system has no mechanical parts and it has moderate size. However, in order to accomplish real implementation, several…

Sound · Computer Science 2017-03-08 Abdulla AlShehhi , M. Luai Hammadih , M. Sami Zitouni , Saif AlKindi , Nazar Ali , Luis Weruaga

We present spectropolarimetric imaging observations of the solar corona at low frequencies (80 - 240 MHz) using the Murchison Widefield Array (MWA). These images are the first of their kind, and we introduce an algorithm to mitigate an…

Solar and Stellar Astrophysics · Physics 2019-09-04 Patrick I. McCauley , Iver H. Cairns , Stephen M. White , Surajit Mondal , Emil Lenc , John Morgan , Divya Oberoi

Coronal magnetic fields are well known to be one of the crucial parameters defining coronal physics and space weather. However, measuring the global coronal magnetic fields remains challenging. The polarization properties of coronal radio…

Solar and Stellar Astrophysics · Physics 2022-07-01 Devojyoti Kansabanik , Divya Oberoi , Surajit Mondal

The future of cm and m-wave astronomy lies with the Square Kilometre Array (SKA), a telescope under development by a consortium of 17 countries that will be 50 times more sensitive than any existing radio facility. Most of the key science…

Astrophysics · Physics 2009-11-13 Simon Johnston

Complex field measurements are increasingly becoming the standard for state-of-the-art astronomical instrumentation. Complex field measurements have been used to characterize a suite of ground, airborne, and space-based heterodyne receiver…

Instrumentation and Methods for Astrophysics · Physics 2018-09-25 Kristina K. Davis , Willem Jellema , Stephen J. C. Yates , Christopher E. Groppi , Jochem J. A. Baselmans , Andrey M. Baryshev

This paper summarizes an investigation around millimeter-wave (mmWave) multimode circular antenna array based beamformer capable of specially encoded data transmission in a wide coverage area. The circular antenna array is capable of an…

Signal Processing · Electrical Eng. & Systems 2021-01-14 Stylianos D. Assimonis , M. Ali Babar Abbasi , Vincent F. Fusco

We investigate the correlation between the integrated low-frequency and infrared (IR) emissions of star-forming galaxies extracted from the {\sl Herschel} Reference Survey. By taking advantage of the GaLactic Extragalactic All-sky MWA…

Astrophysics of Galaxies · Physics 2022-04-05 Tsutomu T. Takeuchi , Shuntaro A. Yoshida , Luca Cortese , O. Ivy Wong , Barbara Catinella , Suchetha Cooray

The Submillimeter Array (SMA), a collaboration between the Smithsonian Astrophysical Observatory and the Academica Sinica Institute for Astronomy and Astrophysics of Taiwan, is an eight-element radio-interferometer designed to operate…

Refraction and diffraction of incoming radio waves by the ionosphere induce time variability in the angular positions, peak amplitudes and shapes of radio sources, potentially complicating the automated cross-matching and identification of…