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Related papers: Study of Low-latitude Ionospheric Scintillation us…

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The ionosphere is a critical component of near-Earth space, shaping GNSS accuracy, high-frequency communications, and aviation operations. For these reasons, accurate forecasting and modeling of ionospheric variability has become…

Density fluctuations in the ionised interstellar medium have a profound effect on radio pulsar observations, through angular scattering, intensity scintillations, and small changes in time delays from dispersion. Here we show that it is…

High Energy Astrophysical Phenomena · Physics 2023-04-12 Daniel J. Reardon , William A. Coles

The ionosphere introduces chromatic distortions on low frequency radio waves, and thus poses a hurdle for 21-cm cosmology. In this paper we introduce time-varying chromatic ionospheric effects on simulated antenna temperature data of a…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Emma Shen , Dominic Anstey , Eloy de Lera Acedo , Anastasia Fialkov

Solar activity, such as flares, produce bursts of high-energy radiation that temporarily enhance the D-region of the ionosphere and attenuate low-frequency radio waves. To track these Sudden Ionospheric Disturbances (SIDs), which disrupt…

Solar and Stellar Astrophysics · Physics 2018-09-11 Sahil Hegde , Monica G. Bobra , Philip H. Scherrer

We have used a relatively long, contiguous VHF observation of a bright cosmic radio source (Cygnus A) with the Very Large Array (VLA) through the nighttime, midlatitude ionosphere to demonstrate the phenomena observable with this…

Space Physics · Physics 2015-06-03 J. F. Helmboldt , T. J. W. Lazio , H. T. Intema , K. F. Dymond

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…

The investigation of the Earth ionosphere both in a quiet and a disturbed states is still desirable. Despite recent progress in its modeling and in estimating the electron concentration along the line of sight by GPS signals, the impact of…

Earth and Planetary Astrophysics · Physics 2018-03-14 O. M. Ulyanov , A. I. Shevtsova , D. V. Mukha , A. A. Seredkina

The LOw Frequency ARray (LOFAR) is a next-generation radio telescope which uses thousands of stationary dipoles to observe celestial phenomena. These dipoles are grouped in various 'stations' which are centred on the Netherlands with…

Solar and Stellar Astrophysics · Physics 2019-08-13 Richard A. Fallows , Ashish Asgekar , Mario M Bisi , Andrew R. Breen , Sander ter Veen

The importance is emphasized of taking into account the channeling along the low index crystallographic axes and planes of a part of low-energy (1-10 keV) recoil ions in measurements of their parameters with crystal scintillators of the…

Instrumentation and Detectors · Physics 2008-12-25 E. M. Drobyshevski

Earth's ionosphere is a perpetual detector of ionizing radiation received from celestial objects, particularly the Sun. Solar ionizing radiation in the form of extreme ultraviolet (EUV) and X-rays during both quiet and active phase of the…

Solar and Stellar Astrophysics · Physics 2026-01-22 Sourav Palit , Subhajit Bhattacharyya , Taraknath Bera , Sandip K. Chakrabarti

Interstellar scintillation (ISS) has been established as the cause of the random variations seen at centimetre wavelengths in many compact radio sources on timescales of a day or less. Observations of ISS can be used to probe structure both…

Radio interferometers, which are designed to observe astrophysical objects in the universe, can also be used to study the Earth's ionosphere. Radio interferometers like the Giant Metrewave Radio Telescope (GMRT) detect variations in…

Instrumentation and Methods for Astrophysics · Physics 2022-04-12 Sarvesh Mangla , Abhirup Datta

NaI(Tl) large crystals are applied in the search for galactic dark matter particles through their elastic scattering off the target nuclei in the detector by measuring the scintillation signal produced. However, energies deposited in the…

In the present paper, we aim to constrain the properties of the ionisation region in a star from the oscillation frequency variation (a so-called glitch) caused by rapid structural variations in this very region. In particular, we seek to…

Solar and Stellar Astrophysics · Physics 2022-07-13 Pierre S. Houdayer , Daniel R. Reese , Marie-Jo Goupil

In this paper, we propose a Bayesian framework to create two dimensional ionospheric images of high spatio-temporal resolution to monitor ionospheric irregularities as measured by the S4 index. Here, we recast the standard Bayesian…

Atmospheric and Oceanic Physics · Physics 2022-05-04 Alexandra Koulouri

We are undertaking a large-scale 5 GHz VLA survey of the northern sky to search for rapid intra-day variability (IDV). Over four observing epochs we found that 56% of the sources showed variability on timescales of hours to several days.…

Detection of the global HI 21 cm signal from Cosmic Dawn and Epoch of Reionization is the key science driver for several ongoing ground-based and future ground/space-based experiments. The crucial spectral features in the global 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-11 Abhirup Datta , Richard Bradley , Jack O. Burns , Geraint Harker , Attila Komjathy , T. Joseph W. Lazio

The paper presents theoretical study of the influence of shape of the spatial spectrum of small-scale ionospheric irregularities on anomalous attenuation of HF radio waves caused by multiple scattering. Several spectrum models are…

Atmospheric and Oceanic Physics · Physics 2007-05-23 Nikolay A. Zabotin , Gennady A. Zhbankov , Eugene S. Kovalenko

The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL@INO) for the study of atmospheric neutrinos. Using the detector resolutions and efficiencies obtained by the INO collaboration from a…

High Energy Physics - Phenomenology · Physics 2013-06-07 Tarak Thakore , Anushree Ghosh , Sandhya Choubey , Amol Dighe