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XMM-Newton observations of the supernova remnant RX J1713.7-3946 and its central source
Ballet, J.; Decourchelle, A.; Giacani, E. +3 more
We present new results from the observations of the supernova remnant (SNR)
A Numerical Model of a Coronal Mass Ejection: Shock Development with Implications for the Acceleration of GeV Protons
Gombosi, T. I.; Roussev, I. I.; Lee, M. A. +3 more
The initiation and evolution of the coronal mass ejection, which occurred on 1998 May 2 in NOAA Active Region 8210, are modeled using a fully three-dimensional, global MHD code. The initial magnetic field for the model is based on magnetogram data from the Wilcox Solar Observatory, and the solar eruption is initiated by slowly evolving the boundar…
GEMS Imaging of Red-Sequence Galaxies at z~0.7: Dusty or Old?
Bell, Eric F.; Somerville, Rachel S.; Wisotzki, Lutz +13 more
We have used the 30'×30' Hubble Space Telescope image mosaic from the Galaxy Evolution from Morphology and Spectral energy distributions (GEMS) project in conjunction with the COMBO-17 deep photometric redshift survey to define a sample of nearly 1500 galaxies with 0.65<=z<=0.75. With this sample, we can study the distr…
Dynamics of solar coronal loops. II. Catastrophic cooling and high-speed downflows
Peter, H.; Hansteen, V. H.; Müller, D. A. N.
This work addresses the problem of plasma condensation and ``catastrophic cooling'' in solar coronal loops. We have carried out numerical calculations of coronal loops and find several classes of time-dependent solutions (static, periodic, irregular), depending on the spatial distribution of a temporally constant energy deposition in the loop. Dyn…
Long-Term Cosmic-Ray Modulation in the Heliosphere
Ferreira, S. E. S.; Potgieter, M. S.
A time-dependent model based on a numerical solution of Parker's transport equation is used to model the modulation of cosmic-ray protons, electrons, and helium for full 11 year and 22 year modulation cycles using a compound approach. This approach incorporates the concept of propagating diffusion barriers, increases in the heliospheric magnetic f…
The nature of the Galactic Center source IRS 13 revealed by high spatial resolution in the infrared
Rigaut, F.; Paumard, T.; Stolovy, S. R. +1 more
High spatial resolution observations in the 1 to 3.5 µm/ region of the Galactic Center source known historically as
A review of the distance and structure of the Large Magellanic Cloud
Alves, David R.
The average of 14 recent measurements of the distance to the Large Magellanic Cloud (LMC) implies a true modulus of 18.50 ± 0.02 mag, and demonstrates a trend in the past 2 years of convergence toward a standard value. The distance indicators reviewed are the red clump, the tip of the red giant branch, Cepheid, RR Lyrae, and Mira variable stars, c…
The XMM-Newton Iron Line Profile of NGC 3783
Nandra, K.; Turner, T. J.; Reeves, J. N. +3 more
We report on observations of the iron K line in the nearby Seyfert 1 galaxy, NGC 3783, obtained in a long, two-orbit (~240 ks) XMM-Newton observation. The line profile obtained exhibits two strong narrow peaks at 6.4 and 7.0 keV, with measured line equivalent widths of 120 and 35 eV, respectively. The 6.4 keV emission is the Kα line from near neut…
A Constant Bar Fraction out to Redshift z ~ 1 in the Advanced Camera for Surveys Field of the Tadpole Galaxy
Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Hirst, Amelia C.
Barlike structures were investigated in a sample of 186 disk galaxies larger than 0.5" that are in the I-band image of the Tadpole galaxy taken with the Hubble Space Telescope Advanced Camera for Surveys. We found 22 clear cases of barred galaxies, 21 galaxies with small bars that appear primarily as isophotal twists in a contour plot, and 11 case…
Cluster observations of earthward flowing plasmoid in the tail
Balogh, A.; Glassmeier, K. -H.; Zhang, H. +10 more
The energetic electrons and ions embedded in Earthward-moving plasmoid structures have been observed. These plasmoids are associated with a rotational local Bz component (bi-polar) signature. Energetic electrons are found to be confined in a smaller spatial region than ions inside the plasmoid. Energetic ions and electrons seem to be a …