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Separating spatial and temporal variations in auroral electric and magnetic fields by Cluster multipoint measurements
Buchert, S.; Karlsson, T.; Marklund, G. +2 more
Available from http://www.copernicus.org/site/EGU/annales/22/7/2463.htm?FrameEngine=false;
XMM-Newton observations of the field of γ-ray burst 980425
Piro, L.; Pian, E.; Palazzi, E. +12 more
The error box of GRB980425 has been observed by XMM- Newton in March 2002, with the aim of measuring the late epoch X-ray emission of the supernova 1998bw and of clarifying its supposed association with the GRB itself. We present here the preliminary results obtained with the EPIC PN camera. Our observations confirm the association between SN 1998…
Evidence for X-ray obscuration in Type II quasar candidates from the Sloan Digital Sky Survey
Comastri, Andrea; Vignali, Cristian; Alexander, Dave M.
Recently, Zakamska et al. selected 291 high-ionization narrow-emission-line active galactic nuclei (AGN) in the redshift range 0.3-0.83 from the Sloan Digital Sky Survey (SDSS) spectroscopic data. The sample includes both type 2 Seyfert galaxies and their higher-luminosity `cousins', Type II quasar candidates. Here we present the results on the X-…
Low-latitude coronal holes during solar maximum
Cranmer, S. R.; Kohl, J. L.; Miralles, M. P.
The Ultraviolet Coronagraph Spectrometer (UVCS) on SOHO has been used to observe large low-latitude coronal holes during solar maximum that produced fast solar wind streams. UVCS observations show that large low-latitude coronal holes at solar maximum, coronal holes of at least 10° in longitude, have plasma properties that seem to bridge the gap b…
Close Association of an Extreme-Ultraviolet Sunspot Plume with Depressions in the Sunspot Radio Emission
Brosius, Jeffrey W.; White, Stephen M.
We obtained coordinated observations of the large sunspot in NOAA Region 8539 on 1999 May 9 and 13 with the Very Large Array and three instruments (CDS, EIT, MDI) aboard the Solar and Heliospheric Observatory satellite. The EUV observations reveal a plume in the sunspot umbra on both observing dates. The plume appears brightest in emission lines f…
X-ray variability of the Narrow Line Seyfert 1 Galaxy PKS 0558-504
Arévalo, P.; Brinkmann, W.; Gliozzi, M. +1 more
We present results from several XMM-Newton observations of the radio-loud Narrow-line Seyfert 1 galaxy (NLS1) PKS 0558-504. We find evidence for strong and persistent X-ray variability, both on short and long time-scales. On short time scales of ⪆2 hours the source varies smoothly by 15-20%; long-term variations by a factor ⪆2 could not be resolve…
Simultaneous Velocity-Intensity Spectral and Cross-Spectral Fitting of Helioseismic Data
Hill, F.; Barban, C.; Kras, S.
Solar oscillation parameters, such as the frequency, are usually estimated by fitting the mode profile in the velocity (V) power spectrum. In this paper, the solar oscillation parameters are derived by simultaneously fitting four observational spectra: V and I (intensity) power, I-V phase difference, and I-V coherence using the model of Severino e…
Observation of continuum radiations from the Cluster fleet: first results from direction finding
Buckley, A.; Canu, P.; Décréau, P. +9 more
Available from http://www.copernicus.org/site/EGU/annales/22/7/2607.htm?FrameEngine=false;
Detection of Saturnian X-ray emission with XMM-Newton
Schmitt, J. H. M. M.; Ness, J. -U.; Robrade, J.
The giant planet Saturn was observed by XMM-Newton in September 2002. We present and analyse these XMM-Newton observations and compare our findings to the Chandra observations of Saturn. Contamination of the XMM-Newton data by optical light is found to be severe in the medium and thin filters, but with the thick filter all optical light is suffici…
STIS observations of FLIERs in NGC 7662
Balick, B.; Corradi, R. L. M.; Patriarchi, P. +1 more
We observed the planetary nebula NGC 7662 with STIS on board the HST to investigate the physical conditions in the microstructures within the nebula at high spatial resolution and to closely examine the physical conditions in FLIERs. We aim to reveal spectroscopic differences in small scale structures moving at about the same velocity as the surro…