Search Publications
Direct Observation of Low Coronal Breakout: Does Breakout Precede or Follow Solar Eruption?
Cho, K. -S.; Moon, Y. -J.; Choe, G. S. +3 more
In this Letter, we report a direct SOHO LASCO C1 observation of low coronal ``magnetic breakout'' that occurred during the coronal mass ejection (CME) on 1998 March 23. The LASCO C1 images show that a slowly expanding, small coronal loop on the northeastern limb erupted, becoming a CME with the typical three-part structure (core, void, and front).…
The iron emission line complex of MCG-5-23-16: the long XMM-Newton look
Ptak, A.; Nandra, K.; Turner, T. J. +9 more
We present the results of the simultaneous XMM-Newton and Chandra observations of the bright Seyfert 1.9 galaxy MCG-5-23-16, which is one of the best known examples of a relativistically broadened iron K\alpha line. We find that: a) the soft X-ray emission is likely to be dominated by photoionized gas, b) the complex iron emission line is best mod…
Tracing the location of the reconnection site from the northern and southern cusps
Fuselier, S. A.; Reme, H.; Trattner, K. J. +2 more
Three-dimensional plasma observations in the cusp have been successfully used to investigate the location of the reconnection site at the magnetopause. This technique uses low-velocity cutoffs in the precipitating and mirrored magnetosheath population traveling along open cusp field lines, which are then used to estimate the distance to the reconn…
INTEGRAL detection of hard X-rays from NGC 6334: nonthermal emission from colliding winds or an AGN?
McBreen, B.; Terrier, R.; Rauw, G. +12 more
Aims.We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the International Gamma-Ray Astrophysics Laboratory INTEGRAL .Methods.The JEM-X monitor and ISGRI imager aboard INTEGRAL and Chandra ACIS imager were used to construct 3-80 keV images and spectra of NGC 6334.Results.The 3-10 keV and 10-35 ke…
An X-Ray Observation of the L1251 Dark Cloud
Simon, Theodore
An X-ray image of the L1251 dark cloud in Cepheus was obtained with the XMM-Newton telescope. More than three dozen sources were detected above a 3 σ limit in X-ray luminosity of LX=1029.0 ergs s-1. Among the detections are eight optically visible T Tauri stars, which had been identified in earlier work from their …
Flow speed inside the brightness boundary of coronal streamers
Suess, S. T.; Nerney, S.
Density measurements in the legs of coronal streamers, where there might be outflow, are reproduced here using a magnetohydrodynamic model of the flow inside the brightness boundary of streamers. The model returns values for the flow speed and stream tube geometry (spreading) between the base and a few solar radii. The flow speed is consistent wit…
Multiple acceleration of protons on the Sun and their free propagation to the Earth on January 20, 2005
Struminsky, A. B.
We analyze the observations of solar protons with energies >80 MeV near the Earth and the January 20, 2005, solar flare in various ranges of the electromagnetic spectrum. Within approximately the first 30 min after their escape into interplanetary space, the solar protons with energies above 80 MeV propagated without scattering to the Earth and…
Thermal Composition and Doppler Velocities in a Transequatorial Loop at the Solar Limb
Brosius, Jeffrey W.
We observed a transequatorial loop (TEL) connecting NOAA Active Regions 10652 and 10653 at the west solar limb on 2004 July 29 with the Extreme-Ultraviolet Imaging Telescope (EIT) and the Coronal Diagnostic Spectrometer (CDS) aboard the Solar and Heliospheric Observatory. Only the loop's northern leg was observed with CDS. The loop appeared bright…
On the Lyman α and β lines in solar coronal streamers
Li, B.; Labrosse, N.; Li, X.
Aims.We investigate the formation of the H I Lyman α and Lyman β lines in an equatorial coronal streamer. Particular attention is paid to frequency redistribution for the scattering of the incident radiation. The properties of the spectral lines are studied.
Methods.The coronal model is given by a global 2.5D three fluid solar wind model with α…
Electron Acceleration and Transport During the November 5, 1998 Solar Flare At ∼13:34 UT
Aulanier, G.; Yan, Y.; Karlický, M. +3 more
This paper deals with a detailed analysis of spectral and imaging observations of the November 5, 1998 (Hα 1B, GOES M1.5) flare obtained over a large spectral range, i.e., from hard X-rays to radiometric wavelengths. These observations allowed us to probe electron acceleration and transport over a large range of altitudes that is to say within sma…