Search Publications
Enigma of a Flare Involving Multiple-Loop Interactions: Emerging, Colliding Loops or Magnetic Breakout?
Holman, Gordon D.; Dennis, Brian R.; Sui, Linhui
We present observations of a C9.4 flare on 2002 June 2 in EUV (TRACE), X-rays (RHESSI), and Hα (Meudon and Ondrejov) showing evidence for multiple-loop interactions as the cause of the flare. The multiwavelength data reveal some striking phenomena that can be used to test different models for solar eruptive events: (1) involvement of a quadrupolar…
Tests of stellar model atmospheres by optical interferometry. III. NPOI and VINCI interferometry of the M0 giant γ Sagittae covering 0.5-2.2 µm
Wittkowski, M.; Hummel, C. A.; Roccatagliata, V. +1 more
Context: .Optical interferometry allows a measurement of the intensity profile across a stellar disc, leading to a direct test and calibration of theoretical model atmospheres as well as to a precise determination of fundamental stellar parameters.
Aims: .We present a comparison of the visual and near-infrared intensity profile of the M0 giant…
The XMM-Newton view of Plaskett's star and its surroundings
Rauw, G.; Pollock, A. M. T.; Stevens, I. R. +1 more
XMM-Newton data of Plaskett's star (HD 47129) are used in order to analyse its X-ray spectrum and variability and hence to derive further constraints on the wind interaction in this early-type binary (O6 I + O7.5 I) system.
Conventional models fail to provide a consistent fit of the European Photon Imaging Camera (EPIC) and Reflexion Grating …First ENA observations at Mars: Solar-wind ENAs on the nightside
Coates, A. J.; Kallio, E.; Fedorov, A. +44 more
We present measurements with an Energetic Neutral Atom (ENA) imager on board Mars Express when the spacecraft moves into Mars eclipse. Solar wind ions charge exchange with the extended Mars exosphere to produce ENAs that can spread into the eclipse of Mars due to the ions' thermal spread. Our measurements show a lingering signal from the Sun direc…
A Radio Burst and Its Associated CME on March 17, 2002
Pick, M.; Krucker, S.; Vourlidas, A. +2 more
In this study, we present a detailed analysis, based on multiwavelength observations and magnetic field extrapolation, of a radio and X-ray event observed on March 17, 2002. This event was accompanied by a Coronal Mass Ejection (CME) observed by the Large-Angle Spectrometric Coronagraph (LASCO) aboard SOHO. During the main event, the Reuven Ramaty…
A structural study of an interior layered deposit in southwestern Candor Chasma, Valles Marineris, Mars, using high resolution stereo camera data from Mars Express
Scholten, F.; Neukum, G.; Hauber, E. +5 more
An interior layered deposit (ILD) within Western Candor Chasma of Valles Marineris, Mars, is examined using data from the High Resolution Stereo Camera of the Mars Express mission. Most ILD layers dip in the same direction as the topographic slope. Exposed, rotated fault blocks of basement lithology appear to penetrate the cover of this ILD deposi…
The hot, warm and cold gas in Arp 227 - an evolving poor group
Trinchieri, G.; Rampazzo, R.; Sheth, K. +6 more
Arp 227 represents a prototypical example of an interacting mixed pair of galaxies located in a low-density environment. We investigate the gas properties of the pair in the X-ray, Hα, HI and CO bands. We also detect two additional members of the group in HI which indicates that the pair constitutes the dominant members of a loose group.
The …Temporal evolution of a staircase ion signature observed by Cluster in the mid-altitude polar cusp
Berchem, J.; Escoubet, C. P.; Pitout, F. +9 more
We use the Cluster string of pearls configuration to investigate temporal variations of ion precipitation in the mid-altitude polar cusp. On 7 Aug. 2004, Cluster 4 was moving poleward through the Northern cusp, followed by Cluster 1, Cluster 2, and finally Cluster 3. The Wind spacecraft detected a Southward turning of the Interplanetary Magnetic F…
A Cloudy/XSPEC Interface
Turner, T. J.; Kraemer, S. B.; Ferland, G. J. +3 more
We discuss new functionality of the spectral simulation code Cloudy that allows the user to calculate grids with one or more initial parameters varied and formats the predicted spectra in the standard FITS format. These files can then be imported into the X-ray spectral analysis software XSPEC and used as theoretical models for observations. We pr…
Is There Any Evident Effect of Coronal Holes on Gradual Solar Energetic Particle Events?
Wang, Yuming; Shen, Chenglong; Wang, S. +1 more
Gradual solar energetic particle (SEP) events are thought to be produced by shocks, which are usually driven by fast coronal mass ejections (CMEs). The strength and magnetic field configuration of the shock are considered the two most important factors for shock acceleration. Theoretically, both of these factors should be unfavorable for producing…