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Related papers: Ionospheric VLF Radio Reflection Analysis System

200 papers

The present study addresses the following questions: How representative of the actual velocities in the solar atmosphere are the Doppler shifts of spectral lines? How reliable is the velocity signal derived from narrowband filtergrams? How…

Solar and Stellar Astrophysics · Physics 2010-02-18 B. Fleck , T. Straus , M. Carlsson , S. M. Jefferies , G. Severino , T. D. Tarbell

This paper presents data from first GPS measurements of global response of the ionosphere to solar flares of September 23, 1998 and July 29, 1999. The analysis used novel technology of a global detection of ionospheric effects from solar…

Solar flares are energetic events in the solar atmosphere that are often linked with solar radio bursts (SRBs). SRBs are observed at metric to decametric wavelengths and are classified into five spectral classes (Type I--V) based on their…

Solar and Stellar Astrophysics · Physics 2023-06-28 Jeremiah Scully , Ronan Flynn , Peter Gallagher , Eoin Carley , Mark Daly

Current post-processing techniques for the correction of atmospheric seeing in solar observations -- such as Speckle interferometry and Phase Diversity methods -- have limitations when it comes to their reconstructive capabilities of solar…

Solar and Stellar Astrophysics · Physics 2020-12-09 John A. Armstrong , Lyndsay Fletcher

White-light flares (WLFs) are crucial for understanding the energy transport and heating processes in the lower solar atmosphere. Systematic studies are highly necessary. However, most WLFs are very weak and difficult to detect. To address…

Solar and Stellar Astrophysics · Physics 2026-04-15 Shuanghong Li , Yongliang Song , Kun Wang , Xianyong Bai , Xiao Yang , Nian Liu , Ziyao Hu

The technique of Faraday tomography is a key tool for the study of magnetised plasmas in the new era of broadband radio polarisation observations. In particular, observations at metre-wavelengths provide significantly better Faraday depth…

High Energy Astrophysical Phenomena · Physics 2018-12-03 Shane P. O'Sullivan , M. Brüggen , C. L. Van Eck , M. J. Hardcastle , M. Haverkorn , T. W. Shimwell , C. Tasse , V. Vacca , C. Horellou , G. Heald

The active broadband (1 kHz-100 MHz) tripole antenna now envisaged to be placed on the European Lunar Lander located at the Lunar South Pole allows for sensitive measurements of the exosphere and ionosphere, and their interaction with the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Marc Klein Wolt , Amin Aminaei , Philippe Zarka , Jan-Rutger Schrader , Albert-Jan Boonstra , Heino Falcke

The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, $R_\omega$, where the local plasma frequency eqals the observing frequency. The radio interferometer LOw Frequency…

Solar and Stellar Astrophysics · Physics 2018-06-13 C. Vocks , G. Mann , F. Breitling , M. M. Bisi , B. Dabrowski , R. Fallows , P. T. Gallagher , A. Krankowski , J. Magdalenic , C. Marque , D. Morosan , H. Rucker

Radial-velocity (RV) signals induce RV variations an order of magnitude larger than the signal created by the orbit of Earth-twins, thus preventing their detection. The goal of this paper is to compare the efficiency of the different…

The solar Ly{\alpha} line emission can be considered as the dominant source of ionization processes in the ionospheric D-region at altitudes above 70 km during unperturbed conditions. However, large sudden impacts of radiation in some other…

Space Physics · Physics 2017-05-24 Aleksandra Nina , Vladimir M. Čadež , Jovan Bajčetić

In addition to X-rays, extreme ultraviolet (EUV) rays radiated from solar flares can cause serious problems, such as communication failures and satellite drag. Therefore, methods for forecasting EUV dynamic spectra during flares are…

Solar and Stellar Astrophysics · Physics 2020-05-14 Toshiki Kawai , Shinsuke Imada , Shohei Nishimoto , Kyoko Watanabe , Tomoko Kawate

Remote-sensing observations of Solar System objects with a space telescope offer a key method of understanding celestial bodies and contributing to planetary formation and evolution theories. The capabilities of Twinkle, a space telescope…

Earth and Planetary Astrophysics · Physics 2019-03-26 Billy Edwards , Giorgio Savini , Giovanna Tinetti , Marcell Tessenyi , Claudio Arena , Sean Lindsay , Neil Bowles

Ground-based observation at frequencies below 30 MHz is hindered by the ionosphere of the Earth and radio frequency interference. To map the sky at these low frequencies, we have proposed the Discovering the Sky at the Longest wavelength…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 Yuan Shi , Yidong Xu , Li Deng , Fengquan Wu , Lin Wu , Qizhi Huang , Shifan Zuo , Jingye Yan , Xuelei Chen

This paper presents a new sample of BL Lac objects selected from a deep (30 mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey, henceforth CBS). The sample is one of the largest well defined samples in the low power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. J. M. Marcha , A. Caccianiga

Despite the continuing importance of ground-based parallax measurements, few active programs remain. Because new members of the solar neighborhood tend towards later spectral types, infrared parallax programs are particularly desirable.…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 Jennifer Lynn Bartlett , Chan Park , Srikrishna Kanneganti , Philip A. Ianna

The main aim of this work is to estimate possible radio GHz emission of extrasolar planets and brown dwarfs and to check if such radiation can be detected by Very Large Baseline Interferometers (VLBI). In the estimation we assume that the…

Earth and Planetary Astrophysics · Physics 2016-08-25 K. Katarzynski , M. Gawronski , K. Gozdziewski

Context. Radial velocity monitoring of very cool dwarfs such as late M- and hot L-dwarfs has become a promising tool to search for rocky planets as well as to follow-up planetary candidates around dwarfs found by transit surveys. These…

The LOw Frequency ARray (LOFAR) has successfully measured cosmic rays for over a decade now. With its dense core of antenna fields in the Netherlands, it is an ideal tool for studying the radio emission from extensive air showers in the…

Existing approaches for the field measurements of the frequency-dependent soil properties take a significant amount of time, making it difficult to obtain new experimental data and study the electrical soil properties further. However, a…

Geophysics · Physics 2022-02-07 Dmitry Kuklin

The non-ducted propagation characteristics of the VLF waves in the inner magnetosphere were studied with respect to their frequency, source localization, and initial wave normal angle, between the wave-normal and the background magnetic…

Space Physics · Physics 2017-08-15 H. Breuillard , D. Mendzhul , O. Agapitov