Search Publications
Missions
Journals
Publication Years
The termination shock near 35° latitude
Burlaga, L. F.; Sheeley, N. R.; Wang, Y. -M. +1 more
The termination shock moves outwards and inwards over timescales of a solar cycle in response to the variations in the average solar wind speed. The amplitude is greater than 50 AU near 35° latitude; the maximum (minimum) distance occurs during the rising (declining) phase of the solar cycle. Shock parameters are distinctly different when the shoc…
Radio Observations of Rapid Acceleration in a Slow Filament Eruption/Fast Coronal Mass Ejection Event
Janardhan, P.; Kundu, M. R.; White, S. M. +4 more
We discuss a filament eruption/coronal mass ejection (CME) event associated with a flare of GOES class M2.8 that occurred on 2001 November 17. This event was observed by the Nobeyama Radio Heliograph (NoRH) at 17 and 34 GHz. NoRH observed the filament during its eruption both as a dark feature against the solar disk and a bright feature above the …
Potential barrier in the electrostatic sheath around a magnetospheric spacecraft
Laakso, H.; Escoubet, P.; Hilgers, A. +4 more
Plasma and field measurements on board magnetospheric spacecraft can be influenced by the spacecraft potential and emitted particles such as photoelectrons and secondary electrons. There exist contradictory requirements for, on one hand, minimizing the spacecraft potential and, on the other hand, minimizing perturbations in the sheath and contamin…
On Collisionless Electron-Ion Temperature Equilibration in the Fast Solar Wind
Laming, J. Martin
We explore a mechanism, entirely new to the fast solar wind, of electron heating by lower hybrid waves to explain the shift to higher charge states observed in various elements in the fast wind at 1 AU relative to the original coronal hole plasma. This process is a variation on that previously discussed for two-temperature accretion flows by Begel…
Interplanetary Transport Mechanisms of Solar Energetic Particles
Zhang, M.; Qin, G.; Dwyer, J. R. +1 more
Numerical simulations of charged particle trajectories in a Parker field with model turbulence are used to study the transport mechanisms of solar energetic particles (SEPs): magnetic focusing, pitch-angle diffusive transport due to magnetic fluctuations, and adiabatic cooling. The results of the simulations are compared with analytical formulae f…
Intense high-altitude auroral electric fields - temporal and spatial characteristics
Nilsson, H.; Buchert, S.; Karlsson, T. +5 more
Available from http://www.copernicus.org/site/EGU/annales/22/7/2485.htm?FrameEngine=false;
Evolution and magnetic topology of the M 1.0 flare of October 22, 2002
Aulanier, G.; Schmieder, B.; Del Zanna, G. +2 more
In this paper we analyse an M 1.0 confined flare observed mainly during its gradual phase. We use the data taken during a coordinated observational campaign between ground based instruments (THEMIS and VTT) and space observatories (SoHO/CDS and MDI, TRACE and RHESSI). We use these multi-wavelength observations to study the morphology and evolution…
Nuclear Properties of a Sample of Nearby Spiral Galaxies from Hubble Space Telescope STIS Imaging
Marconi, A.; Capetti, A.; Carollo, C. M. +17 more
We present surface photometry for the central regions of a sample of 48 spiral galaxies (mostly unbarred and barred of type Sbc or Sc) observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. Surface brightness profiles (SBPs) were derived and modeled with a Nuker law. We also analyzed archival Wide Field Planeta…
The hard X-ray spectrum of the Seyfert galaxy IRAS 18325-5926: reflection from an ionized disc and variable iron K emission
Young, A. J.; Iwasawa, K.; Fabian, A. C. +2 more
We report our analysis of the X-ray spectra of the Seyfert galaxy IRAS 18325-5926 (= Fairall 49) obtained from various X-ray observatories prior to XMM-Newton, including new results from two RXTE and one BeppoSAX observations. A relatively steep continuum slope (Γ~= 2.2) in the 2-15 keV band is confirmed. The continuum spectrum observed with the B…
Observations of the Sun at Vacuum- Ultraviolet Wavelengths from Space. Part I: Concepts and Instrumentation
Wilhelm, Klaus; Marsch, Eckart; Dwivedi, Bhola N. +1 more
Studies of the high-temperature solar atmosphere are to a large extent based on spectroscopic observations of emission lines and continuum radiation in the vacuum-ultraviolet (VUV) wavelength range of the electromagnetic spectrum. In addition, important contributions stem from soft X-ray measurements. Most of the VUV radiation is produced by trans…