English
Related papers

Related papers: Modeling the Ionosphere with GPS and Rotation Meas…

200 papers

Understanding origin and evolution of cosmological magnetic fields requires knowledge of magnetic fields in different extragalactic environments. In this context, a powerful tool is the statistical analysis of the Faraday effect on the…

We present the first spectropolarimetric radio observations that apply Rotation Measure (RM) Synthesis to interferometric data from the Giant Metrewave Radio Telescope (GMRT) at 610 MHz. Spectropolarimetry requires measurement of a large…

Instrumentation and Methods for Astrophysics · Physics 2013-09-19 J. S. Farnes , D. A. Green , N. G. Kantharia

Variations in X-ray and EUV irradiance during solar flares lead to a noticeable increase in the electron concentration in the illuminated part of the Earth's ionosphere. Due to the large amount of experimental data accumulated by Global…

Earth and Planetary Astrophysics · Physics 2024-07-22 Susanna Bekker , Ryan Milligan , Ilya Ryakhovsky

Quantitative helio- and asteroseismology require very precise measurements of the frequencies, amplitudes, and lifetimes of the global modes of stellar oscillation. It is common knowledge that the precision of these measurements depends on…

Astrophysics · Physics 2009-11-13 Thorsten Stahn , Laurent Gizon

Strong singly-ionized magnesium (MgII) absorption lines in quasar spectra typically serve as a proxy for intervening galaxies along the line of sight. Previous studies have found a correlation between the number of these MgII absorbers and…

Astrophysics of Galaxies · Physics 2014-10-16 J. S. Farnes , S. P. O'Sullivan , M. E. Corrigan , B. M. Gaensler

Magnetic fields play vital roles in intracluster media (ICMs), but estimating their strengths and distributions from observations is a major challenge. Faraday rotation measures (RMs) are widely applied to this task, so it is critical to…

High Energy Astrophysical Phenomena · Physics 2020-01-29 Andrew Johnson , Lawrence Rudnick , Thomas Jones , Peter Mendygral , Klaus Dolag

The present investigation is directed at exploring southern polar ionospheric responses to intense space weather events and their correlations with plasma convection and auroral precipitation. The main phases of six geomagnetic storms…

Space Physics · Physics 2025-11-07 Sumanjit Chakraborty , Gopi K. Seemala

Polarised radio synchrotron emission from interstellar, intracluster and intergalactic magnetic fields is affected by frequency-dependent Faraday depolarisation. The maximum polarised intensity depends on the physical properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tigran G. Arshakian , Rainer Beck

Pulsar radio emission undergoes dispersion due to the presence of free electrons in the interstellar medium (ISM). The dispersive delay in the arrival time of pulsar signal changes over time due to the varying ISM electron column density…

A tomographic method is described to quantify the three-dimensional power-spectrum of the ionospheric electron-density fluctuations based on radio-interferometric observations by a two-dimensional planar array. The method is valid to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 L. V. E. Koopmans

We report Faraday rotation measurements of 11 extragalactic radio sources with lines of sight through the Rosette Nebula, a prominent HII region associated with the star cluster NGC 2244. It is also a prototypical example of a "stellar…

Solar and Stellar Astrophysics · Physics 2016-04-27 Allison H. Costa , Steven R. Spangler , Joseph R. Sink , Shea Brown , Sui Ann Mao

Coronal mass ejections (CMEs) are large-scale eruptions of plasma from the Sun that play an important role in space weather. Faraday rotation (FR) is the rotation of the plane of polarization that results when a linearly polarized signal…

Solar and Stellar Astrophysics · Physics 2017-04-12 Jason E. Kooi , Patrick D. Fischer , Jacob J. Buffo , Steven R. Spangler

We consider resonant wave-like dark matter conversion into low-frequency radio waves in the Earth's ionosphere. Resonant conversion occurs when the dark matter mass and the plasma frequency coincide, defining a range $m_{ \text{DM} } \sim…

High Energy Physics - Phenomenology · Physics 2024-05-24 Carl Beadle , Andrea Caputo , Sebastian A. R. Ellis

We utilized the Very Large Array to make multifrequency polarization measurements of 20 radio sources viewed through the IC 1805 HII region and "Superbubble", as well as in the immediate vicinity. The measurements at frequencies between…

Astrophysics of Galaxies · Physics 2018-09-24 Allison H. Costa , Steven R. Spangler

The IAG solar observatory is producing high-fidelity, ultra-high-resolution spectra (R>500000) of the spatially resolved surface of the Sun using a Fourier Transform spectrometer (FTS). The radial velocity (RV) calibration of these spectra…

Instrumentation and Methods for Astrophysics · Physics 2023-11-16 Michael Debus , Sebastian Schäfer , Ansgar Reiners

We can observe the changes of Total Electron Content, TEC, in ionosphere by analyzing the data from GNSS satellites. There are many reports about TEC anomalies after earthquakes, i.e. large earthquakes often disturb the ionosphere. Up to…

Geophysics · Physics 2016-06-13 Takuya Iwata , Ken Umeno

Electron impact ionization is critical in producing the ionospheres on many planetary bodies and, as discussed here, is critical for interpreting spacecraft and telescopic observations of the tenuous atmospheres of the icy Galilean…

Earth and Planetary Astrophysics · Physics 2023-03-22 Shane R. Carberry Mogan , Robert E. Johnson , Audrey Vorburger , Lorenz Roth

We report observations of Faraday rotation measures (RMs) for a sample of 191 extragalactic radio jets observed within the MOJAVE program. Multifrequency VLBA observations were carried out over twelve epochs in 2006 at four frequencies…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-12 T. Hovatta , M. L. Lister , M. F. Aller , H. D. Aller , D. C. Homan , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

Electron density irregularities in the ionosphere are known to be magnetically anisotropic, preferentially elongated along the lines of force. While many studies of their morphology have been undertaken by topside sounding and whistler…

To obtain the most accurate pulse arrival times from radio pulsars, it is necessary to correct or mitigate the effects of the propagation of radio waves through the warm and ionised interstellar medium. We examine both the strength of…

Instrumentation and Methods for Astrophysics · Physics 2016-11-15 R. M. Shannon , J. M. Cordes