Search Publications
Properties of structured coronal mass ejections in solar cycle 23
Bothmer, V.; Tripathi, D.; Cremades, H.
The Solar and Heliospheric Observatory has provided to date doubtlessly the best dataset of coronal observations ever taken over the course of a solar cycle. Structured coronal mass ejections, i.e. events with clear white-light fine structures, have been selected from the dataset of the large angle spectroscopic coronagraph during the period 1996 …
New developments in SOLAR2000 for space research and operations
Tobiska, W. Kent; Bouwer, S. Dave
The SOLAR2000 (S2K) project provides solar spectral irradiances and integrated solar irradiance proxies for space researchers as well as ground- and space-based operational users. The S2K model currently represents empirical solar irradiances and integrated irradiance proxies covering the spectral range from the X-rays through the far infrared and…
Forces governing coronal mass ejections
Vršnak, B.
Kinematics of CMEs is analyzed to get an insight into the properties of forces partaking in the eruption. It is demonstrated that the Lorentz force plays a dominant role within a distance of a few solar radii. In the distance range 1 30 solar radii, the inferred values of the Lorentz-force acceleration aL on average decrease with the he…
Observation of energy-dependent ionic charge states in impulsive solar energetic particle events
Klecker, B.; Kistler, L. M.; Kucharek, H. +3 more
We measured the mean ionic charge state of Fe in several 3He-rich and heavy-ion rich energetic particle events during the time period 1998 2000. We combined the ionic charge measurements of CELIAS/STOF onboard SOHO (10 100 keV/nuc) with the measurements of SEPICA onboard ACE (180 550 keV/nuc) to investigate the ionic charge distribution…
Statistical analysis of the sunspot area and magnetic flux variations in 1996 2005 extracted from the Solar Feature Catalogue
Zharkova, V. V.; Zharkov, S. I.
This research presents some statistical properties of sunspots and their magnetic fields extracted in from May 1996 to May 2005 from the SOHO/MDI full disk whitelight images and magnetograms for the searchable Solar Feature Catalogue (SFC) using the automated pattern recognition techniques. A comparison of the total sunspot areas on a given day fr…
Propagation of interplanetary shocks through the solar wind and magnetosheath
Němeček, Z.; Šafránková, J.; Přech, L. +1 more
In order to estimate the propagation of interplanetary (IP) shocks in the solar wind and magnetosheath, we have analyzed a number of events for which simultaneous observations in the solar wind and magnetosheath were available. Among these events, those for which the arrival of the shock is observed by at least four spacecraft located in the solar…
ISS-SOLAR: Total (TSI) and spectral (SSI) irradiance measurements
Fröhlich, C.; Thuillier, G.; Schmidtke, G.
The primary objective of the ISS-SOLAR mission on Columbus (to be launched in 2006) is the quasi-continuous measurement of the solar irradiance variability with highest possible accuracy. For this reason the total spectral range will be recorded simultaneously from 3000 to 17 nm by three sets of instruments: SOVIM is combining two types of absolut…
The extreme Halloween 2003 solar flares (and Bastille Day, 2000 Flare), ICMEs, and resultant extreme ionospheric effects: A review
Tsurutani, B. T.; Judge, D. L.; Gonzalez, W. D. +5 more
Extreme solar flares can cause extreme ionospheric effects. The Oct 28, 2003 flare caused a ∼25 TECU (a total electron content unit is 10 16 electron/m 2 column density), or a ∼30%, increase in the local noon equatorial ionospheric column density. This enhancement occurred within ∼5 min. This TEC increase was ∼5 times the TEC…
Calibration of space instrumentation with synchrotron radiation
Richter, M.; Gottwald, A.; Scholze, F. +2 more
For many years, synchrotron radiation as emitted from electron storage rings has been established as a versatile tool for photon metrology in the spectral range from ultraviolet radiation to X-rays. In particular, various radiometric techniques have been developed and applied for the calibration of space instrumentation. In this context, the prese…
Magnetic reconfiguration before the X 17 Solar flare of October 28 2003
Mandrini, C. H.; Schmieder, B.; Démoulin, P. +3 more
An active region (AR) NOAA 10486, which produced a large number of X-ray flares during October November 2003, was observed during a multi-wavelength campaign with ground based and space instruments. We focus our analysis on the observations of October 28, 2003. The magnetic field was observed with THEMIS (Na D1) and MDI (Ni I), the chromosphere wi…