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Related papers: Assessing Ionospheric Scintillation Risk for Direc…

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We carry out a shape and weak lensing analysis of Low Frequency Array (LOFAR) radio sources and Hyper Suprime-Cam (HSC) optical sources within the European Large Area Infrared Space Observatory Survey-North 1 (ELAIS-N1) field. Using HSC…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 Jinyi Liu , Reinout van Weeren , Huub Rottgering , Konrad Kuijken

Temporal broadening is a commonly observed property of fast radio bursts (FRBs), associated with turbulent media which cause radiowave scattering. Similarly to dispersion, scattering is an important probe of the media along the line of…

We modelled the two major layer of Earth's ionosphere, the F-layer and the D-layer, by a simplified spatial model with temporal variance to study the chromatic ionospheric effects on global 21-cm observations. From the analyses, we found…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Emma Shen , Dominic Anstey , Eloy de Lera Acedo , Anastasia Fialkov , Will Handley

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

Direct satellite-to-device (DS2D) communication enables standard mobile devices to connect directly to low Earth orbit (LEO) satellites, providing global coverage without reliance on terrestrial infrastructure. However, the DS2D uplink is…

Signal Processing · Electrical Eng. & Systems 2026-02-24 Rajan Shrestha , Hayder Al-Hraishawi

Quasi-continuous observations of PSR B03239+54 over 20 days using the Nanshan 25-m telescope at 1540 MHz have been used to study the effects of refractive scintillation on the pulsar flux density and diffractive scintillation properties.…

Astrophysics · Physics 2009-11-13 N. Wang , Z. Yan , R. N. Manchester , H. X. Wang

Radio emission propagating over an Earth-pulsar line of sight provides a unique probe of the intervening ionized interstellar medium (ISM). Variations in the integrated electron column density along this line of sight, or dispersion measure…

High Energy Astrophysical Phenomena · Physics 2020-04-08 M. T. Lam , T. J. W. Lazio , T. Dolch , M. L. Jones , M. A. McLaughlin , D. R. Stinebring , M. Surnis

We report measurements of time delays of up to 8 minutes in the centimeter wavelength variability patterns of the intra-hour scintillating quasar PKS 1257-326 as observed between the VLA and the ATCA on three separate epochs. These time…

We present broadband ionospheric scintillation observations of highly defined symmetric quasi-periodic oscillations (QPO: Maruyama 1991) caused by plasma structures in the midlatitude ionosphere using the LOw Frequency ARray (LOFAR: van…

Space Physics · Physics 2023-12-08 Hannah Trigg , Gareth Dorrian , Ben Boyde , Alan Wood , Richard Fallows , Maaijke Mevius

The observed interstellar scintillation pattern of an intra-day variable radio source is influenced by its source structure. If the velocity of the interstellar medium responsible for the scattering is comparable to the earth's, the vector…

Astrophysics · Physics 2009-11-07 J-P Macquart , D. L. Jauncey

A scattering resonance is one of the most striking quantum effects in low-temperature molecular collisions. Predicted decades ago theoretically, they have only been resolved experimentally for systems involving at most four atoms. Extension…

Intraday Variability of compact extragalactic radio sources can be interpreted as quenched scintillation due to turbulent density fluctuations of the nearby ionized interstellar medium. We demonstrate that the statistical analysis of IDV…

Astrophysics · Physics 2007-05-23 T. Beckert , L. Fuhrmann , G. Cimo , T. P. Krichbaum , A. Witzel , J. A. Zensus

Radio pulsars, as highly coherent point sources, serve as powerful probes of the ionized interstellar medium (IISM). Pulsar scintillation observations have revealed inverted arclets on the secondary spectrum, indicating quasilinearly…

Astrophysics of Galaxies · Physics 2026-04-14 Zhu Xu , Xun Shi

Phase stability at low radio frequencies is severely impacted by ionospheric propagation delays. Radio interferometers such as the Giant Metrewave Radio Telescope (GMRT) are capable of detecting changes in the ionosphere's total electron…

Instrumentation and Methods for Astrophysics · Physics 2025-07-01 Dipanjan Banerjee , Abhik Ghosh , Sushanta K Mondal , Parimal Ghosh

The solar radiation focusing effect is related to the specific phenomenon of propagation of the Sun-emitted HF and VHF waves through terrestrial ionosphere. This natural effect is observed with ground-based radio instruments running within…

Intense geomagnetic storms can have a strong impact on the signals (termed ionospheric scintillations) emitted by any global navigation satellite system (GNSS). The paper reports the first studies of scintillations at the Indore region on…

Space Physics · Physics 2023-04-26 Deepthi Ayyagari , Sumanjit Chakraborty , Abhirup Datta , Saurabh Das

Despite being an integral part of the vision of quantum Internet, Earth-to-satellite (uplink) quantum communications have been considered more challenging than their satellite-to-Earth (downlink) counterparts due to the severe channel-loss…

Quantum Physics · Physics 2025-12-15 Ziqing Wang , Timothy C. Ralph , Ryan Aguinaldo , Robert Malaney

We report long-term scintillation observations of 18 pulsars in the DM range 3-35 pc cm^{-3} carried out during 1993-1995 using the Ooty Radio Telescope at 327 MHz. These observations were made with the aim of studying refractive effects in…

Astrophysics · Physics 2009-10-31 N. D. Ramesh Bhat , A. Pramesh Rao , Yashwant Gupta

We have conducted the first systematic search for interday variability in a large sample of extragalactic radio sources at 15 GHz. From the sample of 1158 radio-selected blazars monitored over a $\sim$10 year span by the Owens Valley Radio…

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