Search Publications
Reconstruction of the reconnection rate from Cluster measurements: First results
Penz, T.; Kubyshkin, I. V.; Nakamura, R. +6 more
A model of transient time-dependent magnetic reconnection is used to describe the behavior of nightside flux transfers (NFTEs) in the Earth's magnetotail. On the basis of the analytical approach to reconnection developed by Heyn and Semenov (1996) and Semenov et al. (2004a) we calculate the magnetic field and plasma bulk velocity time series obser…
The proper motion of the isolated neutron star RX J1605.3+3249
Haberl, F.; Motch, C.; Schwope, A. +3 more
We obtained deep optical imaging of the thermally emitting X-ray bright and radio-quiet isolated neutron star
Helium Line Formation and Abundance in a Solar Active Region
Andretta, V.; Teriaca, L.; Mauas, P. J. D. +3 more
An observing campaign (SOHO JOP 139), coordinated between ground-based and Solar and Heliospheric Observatory (SOHO) instruments, has been planned to obtain simultaneous spectroheliograms of the same active region in several spectral lines. The chromospheric lines Ca II K, Hα, and Na I D, as well as He I 10830, 5876, 584, and He II 304 Å lines hav…
A Small X-Ray Corona of the Narrow-Angle Tail Radio Galaxy NGC 1265 Soaring through the Perseus Cluster
Sun, M.; Jones, C.; Jerius, D.
A deep Chandra observation of NGC 1265 (3C 83.1B), the prototype for the narrow-angle tail (NAT) radio galaxy, reveals a small cool X-ray thermal corona (~0.6 keV) embedded in the hot ICM of the Perseus cluster (~6.7 keV). The corona is asymmetric with a sharp edge (~2.2", or 0.8 kpc from the nucleus) to the south and an extension to the north (at…
Dynamics of the Saturnian inner magnetosphere: First inferences from the Cassini magnetometers about small-scale plasma transport in the magnetosphere
André, N.; Russell, C. T.; Dougherty, M. K. +2 more
The Cassini magnetometers reveal a very dynamic plasmadisc within the inner Saturnian magnetosphere during the first three orbits of the Cassini orbital tour. This corotation-dominated region is known to contain various neutral and plasma populations and Voyager spacecraft observations suggest important radial transport processes redistribute the …
Magnetic Properties at Footpoints of Hot and Cool Loops
Tsuneta, Saku; Katsukawa, Yukio
Observations of the solar corona with Yohkoh, the Solar and Heliospheric Observatory, and the Transition Region and Coronal Explorer (TRACE) have revealed that individual coronal loops of active regions have their own temperatures from 1 to 5 MK. The hot (2-5 MK) Soft X-Ray Telescope (SXT) loops appear to require more heating energy than the cool …
X-ray emission from NGC 1808: more than a complex starburst
Mas-Hesse, J. M.; Guainazzi, M.; Santos-Lleó, M. +5 more
Earlier observations of NGC 1808 in various wavebands (X-ray, optical, near-infrared, radio) provided evidence for the existence of either a starburst or a Seyfert 2 nucleus. We here present the results of multiwavelength XMM-Newton and Chandra observations, which directly prove the co-existence of thermal diffuse plasma and non-nuclear unresolved…
The extended hard X-ray emission from the Vela Plerion
Cusumano, G.; Bocchino, F.; Mineo, T. +2 more
We present the results of a broad band (3-200 keV) spectral analysis of BeppoSAX and XMM-Newton observations of the Vela plerion. The hard X-ray (>15 keV) emission is found to be extended over a region of 12'-15' radius, corresponding to a size of about 1.0-1.3 pc for a source distance of 290 pc. A single power law does not give an acceptable f…
The star cluster population of NGC 5253
Sauvage, M.; Cresci, G.; Vanzi, L.
We present a detailed analysis of the star cluster population in the starburst galaxy NGC 5253. Our work is based on HST optical and VLT Ks images. We detect more than 300 clusters, and for all of them we derive the photometry in the V, I and Ks bands and built a color-color V-I/V-Ks diagram. After correction for star contamination, we matched 115…
High-Cadence Radio Observations of an EIT Wave
Thompson, B. J.; White, S. M.
Sensitive radio observations of the 1997 September 24 EIT wave show its velocity to be 830 km s-1. The wave first appears a short distance from the flare site, and its trajectory projects back to the flare site at the peak of the impulsive phase. The radio spectrum appears to be consistent with optically thin coronal emission rather tha…