159 citations · 1.1k across the 18 of their papers we have counts for
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Probing Ionospheric Structures using the LOFAR radio telescope
M. Mevius, S. van der Tol, V. N. Pandey +24
LOFAR is the LOw Frequency Radio interferometer ARray located at mid-latitude (). Here, we present results on ionospheric structures derived from 29 LOFAR nighttim…
Collaborative Randomized Beamforming for Phased Array Radio Interferometers
Orhan Ocal, Paul Hurley, Giovanni Cherubini +1
The Square Kilometre Array (SKA) will form the largest radio telescope ever built and such a huge instrument in the desert poses enormous engineering and logistic challenges. Algor…
Lunar occultation of the diffuse radio sky: LOFAR measurements between 35 and 80 MHz
H. K. Vedantham, L. V. E. Koopmans, A. G. de Bruyn +91
We present radio observations of the Moon between and MHz to demonstrate a novel technique of interferometrically measuring large-scale diffuse emission extending far bey…
Robust Radio Interferometric Calibration Using the t-Distribution
S. Kazemi, S. Yatawatta
A major stage of radio interferometric data processing is calibration or the estimation of systematic errors in the data and the correction for such errors. A stochastic error (noi…
Radio Interferometric Calibration via Ordered-Subsets Algorithms: OS-LS and OS-SAGE calibrations
S. Kazemi, S. Yatawatta, S. Zaroubi
The main objective of this work is to accelerate the Maximum-Likelihood (ML) estimation procedure in radio interferometric calibration. We introduce the OS-LS and the OS-SAGE radio…
Initial deep LOFAR observations of Epoch of Reionization windows: I. The North Celestial Pole
S. Yatawatta, A. G. de Bruyn, M. A. Brentjens +86
The aim of the LOFAR Epoch of Reionization (EoR) project is to detect the spectral fluctuations of the redshifted HI 21cm signal. This signal is weaker by several orders of magnitu…
Clustered Calibration: An Improvement to Radio Interferometric Direction Dependent Self-Calibration
Sanaz Kazemi, Sarod Yatawatta, Saleem Zaroubi
The new generation of radio synthesis arrays, such as LOFAR and SKA, have been designed to surpass existing arrays in terms of sensitivity, angular resolution and frequency coverag…
The LOFAR radio environment
A. R. Offringa, A. G. de Bruyn, S. Zaroubi +93
Aims: This paper discusses the spectral occupancy for performing radio astronomy with the Low-Frequency Array (LOFAR), with a focus on imaging observations. Methods: We have analys…
Clustered Radio Interferometric Calibration
Sanaz Kazemi, Sarod Yatawatta, Saleem Zaroubi
This paper introduces an amendment to radio interferometric calibration of sources below the noise level. The main idea is to employ the information of the stronger sources' measur…
Radio Interferometric Calibration Using The SAGE Algorithm
S. Kazemi, S. Yatawatta, S. Zaroubi +3
The aim of the new generation of radio synthesis arrays such as LOFAR and SKA is to achieve much higher sensitivity, resolution and frequency coverage than what is available now, e…