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Related papers: Statistical study of auroral omega bands

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We present three eastward-expanding auroral surge (EEAS) events that were observed intermittently at intervals of about 15 min in the post-midnight sector (01:55-02:40 MLT) by all-sky imagers and magnetometers in northern Europe. It was…

The aim of the Swedish-Japanese EISCAT campaign in February 1999 was to measure the ionospheric parameters inside and outside the auroral arcs. The ion line radar experiment was optimised to probe the E-region and lower F-region with as…

We report both decreasing and increasing trends in the patch sizes during pulsating aurora events. About 150 pulsating auroral events over the Fennoscandian Lapland have been successfully analyzed for their average patch size, total patch…

Space Physics · Physics 2020-11-19 N. Partamies , K. Bolmgren , E. Heino , N. Ivchenko , J. E. Borovsky , H. Sundberg

This paper shows a statistical analysis of 10.2 kHz Omega broadcasts of an artificial signal broadcast from ground stations, propagated in the plasmasphere, and detected using an automatic detection method we developed. We study the…

Space Physics · Physics 2017-07-28 I Made Agus Dwi Suarjaya , Yoshiya Kasahara , Yoshitaka Goto

We present high-cadence observations and simulations of the solar photosphere, obtained using the Rapid Oscillations in the Solar Atmosphere imaging system and the MuRAM magneto-hydrodynamic code, respectively. Each dataset demonstrates a…

Solar and Stellar Astrophysics · Physics 2015-06-03 D. B. Jess , S. Shelyag , M. Mathioudakis , P. H. Keys , D. J. Christian , F. P. Keenan

We present a feasibility study for a high frame rate, short baseline auroral tomographic imaging system useful for estimating parametric variations in the precipitating electron number flux spectrum of dynamic auroral events. Of particular…

We interpret the linear polarization structures observed in extragalactic radio sources, even those oriented at oblique angles to the jet flows, to be due to oblique, relativistic shock fronts in the emitting regions. Many sources exhibit…

Astrophysics · Physics 2007-05-23 H. D. Aller , M. F. Aller , P. A. Hughes

We investigate the angular correlation function, omega(theta), and third and fourth-order hierarchical moments of a survey with approx. 70000 faint galaxies detected on a total area 1.74 sq. deg. to a limit of R=23.5. The omega(theta)…

Astrophysics · Physics 2009-10-30 Nathan Roche , Steve Eales

We have developed a technique to systematically discover and study high-redshift supernovae that can be used to measure the cosmological parameters. We report here results based on the initial seven of >28 supernovae discovered to date in…

We study the angular clustering of point sources in The GMRT (Giant Meter Wave Telescope) Sky Survey (TGSS). The survey at 150 MHz with delta > -53.5 degrees has a sky coverage of 3.6 pi steradians, i.e., 90% of the whole sky. We created…

Astrophysics of Galaxies · Physics 2019-06-04 Sandeep Rana , J. S. Bagla

The multi-object fibre-fed spectrograph AAOmega at the Anglo-Australian Telescope has been used to establish and measure accurate (<1 kms-1) radial velocities for a new sample of members in the outer parts of the stellar system omega…

Solar and Stellar Astrophysics · Physics 2015-06-04 G. S. Da Costa

We investigate the long-term evolution of an initially buoyant magnetic flux tube emerging into a gravitationally-stratified coronal hole environment and report on the resulting oscillations and outflows. We perform 2.5D nonlinear numerical…

Solar and Stellar Astrophysics · Physics 2012-04-02 J. A. McLaughlin , G. Verth , V. Fedun , R. Erdélyi

Swirl-shaped flow structures have been observed throughout the solar atmosphere, in both emission and absorption, at different altitudes and locations, and are believed to be associated with magnetic structures. However, the distribution…

Solar and Stellar Astrophysics · Physics 2024-12-06 Quan Xie , Jiajia Liu , Chris J. Nelson , Robert Erdélyi , Yuming Wang

Recently, polarization angle (PA) orthogonal jumps over millisecond timescales were discovered from three bursts of a repeating fast radio burst source FRB 20201124A by the FAST telescope. In general, PA jumps can arise from the coherent or…

High Energy Astrophysical Phenomena · Physics 2025-12-03 Yuanhong Qu , Bing Zhang , Pawan Kumar

High spatial and temporal resolution images of a sunspot, obtained simultaneously in multiple optical and UV wavelengths, are employed to study the propagation and damping characteristics of slow magnetoacoustic waves up to transition…

Solar and Stellar Astrophysics · Physics 2017-09-20 S. Krishna Prasad , D. B. Jess , T. Van Doorsselaere , G. Verth , R. J. Morton , V. Fedun , R. Erdelyi , D. J. Christian

Submarine eruptions, accounting for over 80% of Earth's volcanic activity, primarily occur along mid-ocean ridges, where shallow magmatic systems are accessible to high-resolution imaging. Yet, their remoteness often leaves them undetected.…

We have used the two-degree field (2dF) multi-fibre spectrograph of the Anglo-Australian Telescope to search for candidate members of the unusual globular cluster omega Centauri at and beyond the cluster tidal radius. Velocities with an…

Astrophysics · Physics 2009-11-13 G. S. Da Costa , M. G. Coleman

We present observations of the region between 5deg < l < 45deg and |b| < 3deg, in the OH 1612 MHz line, taken from 1993 to 1995 with the VLA. These observations are the last part of a larger survey, covering |l| < 45deg and |b| < 3deg, with…

Astrophysics · Physics 2019-08-17 M. Sevenster , H. v. Langevelde , R. Moody , J. Chapman , H. Habing , N. Killeen

Solar chromospheric observations of sunspot umbrae offer an exceptional view of magneto-hydrodynamic wave phenomena. In recent years, a wealth of wave signatures related to propagating magneto-acoustic modes have been presented, which…

We have used the Australia Telescope Compact Array (ATCA) to make a sensitive (5-$\sigma$ $\simeq$ 100 mJy) search for maser emission from the 4765-MHz $^2\Pi_{1/2}$ F=1$\to$0 transition of OH. Fifty five star formation regions were…

Astrophysics · Physics 2009-11-07 R. Dodson , S. P. Ellingsen , M. A. Voronkov
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