English
Related papers

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

200 papers

The wide adoption of low-frequency radio interferometers as a tool for deeper and higher resolution astronomical observations has revolutionised radio astronomy. Despite their construction from static, relatively simple dipoles, the sheer…

Instrumentation and Methods for Astrophysics · Physics 2021-02-02 A. Chokshi , J. L. B. Line , N. Barry , D. Ung , D. Kenney , A. McPhail , A. Williams , R. L. Webster

Reliable, autonomously, deployment of telescopes enables a wide range of possible science cases. In this paper, we present a method for multi-stage telescope alignment with a simple commercial imaging sensor. For these studies, we use a…

Instrumentation and Methods for Astrophysics · Physics 2025-08-28 Solvay Blomquist , Heejoo Choi , Hyukmo Kang , Hayden Kim , Kevin Derby , Pierre Nicolas , Joanna Rosenbluth , Patrick Ingraham , Ewan S. Douglas , Daewook Kim

We present the results of a programme of scanning and mapping observations of astronomical masers and Jupiter designed to characterise the performance of the Mopra Radio Telescope at frequencies between 16-50 GHz using the 12-mm and 7-mm…

This manual is intended to help ALMA and other interferometer users improve images by recognising limitations and how to overcome them and deciding when and how to use self-calibration. The images provided by the ALMA Science Archive are…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 A. M. S. Richards , E. Moravec , S. Etoka , E. B. Fomalont , A. F. Pérez-Sánchez , M. C. Toribio , R. A. Laing

The advent of large aperture arrays, such as the currently under construction Square Kilometer Array (SKA), allows for observing the universe in the radio-spectrum at unprecedented resolution and sensitivity. However, these telescopes…

Instrumentation and Methods for Astrophysics · Physics 2024-12-04 S. Wang , S. Prunet , S. Mignot , A. Ferrari

Optical interferometers increasingly use single-mode fibers as spatial filters to convert varying wavefront distortion into intensity fluctuations which can be monitored for accurate calibration of fringe amplitudes. Here I propose using an…

Astrophysics · Physics 2009-11-06 J. D. Monnier

The Mingantu Spectral Radioheliograph (MUSER), a new generation of solar dedicated radio imaging-spectroscopic telescope, has realized high-time, high-angular, and high-frequency resolution imaging of the sun over an ultra-broadband…

Instrumentation and Methods for Astrophysics · Physics 2022-10-17 Zhichao Zhou , Yihua Yan , Linjie Chen , Wei Wang , Suli Ma

We have developed a multi-pixel beamformer technique, which can be used for enhancing the capabilities for studying pulsars using an interferometric array. Using the Giant Metrewave Radio Telescope (GMRT), we illustrate the application of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Jayanta Roy , Bhaswati Bhattacharyya , Yashwant Gupta

Cold-atom interferometers commonly face systematic effects originating from the coupling between the trajectory of the atomic wave packet and the wave front of the laser beams driving the interferometer. Detrimental for the accuracy and the…

Atomic Physics · Physics 2020-03-13 M. Altorio , L. A. Sidorenkov , R. Gautier , D. Savoie , A. Landragin , R. Geiger

Communication systems at millimeter-wave (mmW) and sub-terahertz frequencies are of increasing interest for future high-data rate networks. One critical challenge faced by phased array systems at these high frequencies is the efficiency of…

Signal Processing · Electrical Eng. & Systems 2022-02-18 Benjamin W. Domae , Ruifu Li , Danijela Cabric

Millimeter-wave (mmWave) and terahertz (THz) communication systems adopt large antenna arrays to ensure adequate receive signal power. However, adjusting the narrow beams of these antenna arrays typically incurs high beam training overhead…

Information Theory · Computer Science 2023-02-15 Shoaib Imran , Gouranga Charan , Ahmed Alkhateeb

Enabling highly-mobile millimeter wave (mmWave) and terahertz (THz) wireless communication applications requires overcoming the critical challenges associated with the large antenna arrays deployed at these systems. In particular, adjusting…

Signal Processing · Electrical Eng. & Systems 2021-11-16 Gouranga Charan , Tawfik Osman , Andrew Hredzak , Ngwe Thawdar , Ahmed Alkhateeb

High resolution (~1 arcminute) astronomical imaging at low frequency (below 150 MHz) has only recently become practical with the development of new calibration algorithms for removing ionospheric distortions. In addition to opening a new…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. S. Cohen , H. J. A. Röttgering

Next generation radio telescope arrays are being designed and commissioned to accurately measure polarized intensity and rotation measures across the entire sky through deep, wide-field radio interferometric surveys. Radio interferometer…

Instrumentation and Methods for Astrophysics · Physics 2017-08-02 P. Jagannathan , S. Bhatnagar , U. Rau , A. R. Taylor

Telescopes with unobstructed pupil are known to deliver clean point spread function (PSF) to their focal plane, in contrast to traditional telescopes with obstructed pupil. Recent progress in the manufacturing aspheric surfaces and mounting…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Balasubramanian Singaravelu , Remi A. Cabanac

Many aspects of the Atacama Large Millimeter Array (ALMA) instrument are still unknown due to its young age. One such aspect is the true nature of the primary beam of each baseline, and how changes to the individual primary beams affect…

Instrumentation and Methods for Astrophysics · Physics 2017-02-07 Kara Kundert , Urvashi Rau , Edwin Bergin , Sanjay Bhatnagar

In this third paper of a series on radio weak lensing for cosmology with the Square Kilometre Array, we scrutinise synergies between cosmic shear measurements in the radio and optical/near-IR bands for mitigating systematic effects. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Stefano Camera , Ian Harrison , Anna Bonaldi , Michael L. Brown

Performance of digitally beamformed phased arrays relies on accurate calibration of the array by obtaining gains of each antenna in the array. The stations of the Square Kilometer Array-Low (SKA-Low) are such digital arrays, where the…

Instrumentation and Methods for Astrophysics · Physics 2024-01-17 Jishnu N. Thekkeppattu , Randall B. Wayth , Marcin Sokolowski

We investigate interferometric techniques to estimate the deflection angle of an optical beam and compare them to the direct detection of the beam deflection. We show that quantum metrology methods lead to a unifying treatment for both…

Quantum Physics · Physics 2020-08-12 S. P. Walborn , G. H. Aguilar , P. L. Saldanha , L. Davidovich , R. L. de Matos Filho

Direction-dependent instrumental polarisation introduces wide-field polarimetric aberrations and limits the dynamic range of low-frequency interferometric images. We therefore provide a detailed two-dimensional analysis of the Giant…

Instrumentation and Methods for Astrophysics · Physics 2014-07-03 J. S. Farnes