Search Publications
A reinterpretation of the energy balance in active region loops following new results from Hinode EIS
Bradshaw, S. J.
Context: New observations made by the Hinode EUV Imaging Spectrometer have revealed persistent redshifts in solar active region loops in the temperature range 105.6 ≤ T ≤ 106.4 K. The presence of redshifts, interpreted as bulk downflows, indicates that the loops are undergoing radiative cooling rather than continuous heating.…
XMM-Newton observations of ζ Orionis (O9.7 Ib): a collisional ionization equilibrium model
Raassen, A. J. J.; van der Hucht, K. A.; Cassinelli, J. P. +1 more
We present XMM-Newton observations of the O supergiant ζ Orionis (O9.7 Ib). The spectra are rich in emission lines over a wide range of ionization stages. The rgs spectra show for the first time lines of low ion stages such as C VI, N VI, N VII, and O VII. The line profiles are symmetric and rather broad ({{FWHM}}≈ 1500 km s-1) and show…
XMM-Newton observations of the Small Magellanic Cloud: Long term evolution of frequently observed Be/X-ray binaries
Haberl, F.; Eger, P.
Aims: To follow the long term evolution of Be/X-ray binaries in the Small Magellanic Cloud (SMC) we analyzed twenty-two XMM-Newton observations towards the calibration target 1E 0102.2-7218 and seven observations towards the neighboring region around the eclipsing binary HD 5980.
Methods: The data from the European Photon Imaging Cameras (EPIC…
XMM-Newton observations of the Galactic globular clusters NGC 2808 and NGC 4372
Servillat, M.; Webb, N. A.; Barret, D.
Aims:Galactic globular clusters harbour binary systems that are detected as faint X-ray sources. These close binaries are thought to play an important role in the stability of the clusters by liberating energy and delaying the inevitable core collapse of globular clusters. The inventory of close binaries and their identification is therefore essen…
Embedded clusters in NGC 1808 central starburst. Near-infrared imaging and spectroscopy
Alloin, D.; Galliano, E.
Context: In the course of a mid-infrared imaging campaign of close-by active galaxies, we discovered the mid-infrared counterparts of bright compact radio sources in the central star-forming region of NGC 1808.
Aims: We aim at confirming that these sources are deeply embedded, young star clusters and at deriving some of their intrinsic propert…
Imaging ejecta from the final flash star V605 Aquilae
Lebzelter, T.; Hinkle, K. H.; Joyce, R. R. +4 more
Aims:We investigated the cloud of ejecta resulting from the mass loss associated with the final helium shell flash in V605 Aql.
Methods: V605 Aql was imaged at high spatial resolution in both optical emission lines and the infrared continuum using HST/WFPC2 and Gemini/Hokupa'a+QUIRC, respectively. The He I 10 830 Å spectrum was also observed. …
Large-scale horizontal flows in the solar photosphere. III. Effects on filament destabilization
Bommier, V.; Schmieder, B.; Rondi, S. +7 more
Aims:We study the influence of large-scale photospheric motions on the destabilization of an eruptive filament, observed on October 6, 7, and 8, 2004, as part of an international observing campaign (JOP 178).
Methods: Large-scale horizontal flows were investigated from a series of MDI full-disc Dopplergrams and magnetograms. From the Dopplergr…
Penumbral models in the light of Hinode spectropolarimetric observations
Bellot Rubio, L. R.; Jurčák, J.
Aims:The realism of current models of the penumbra is assessed by comparing their predictions with the plasma properties of penumbral filaments as retrieved from spectropolarimetric observations.
Methods: The spectropolarimeter onboard Hinode allows us, for the first time, to distinguish the fine structure of the penumbra. Therefore, we can us…
The changing accretion states of the intermediate polar MU Camelopardalis
Krumpe, M.; Schwope, A. D.; Schwarz, R. +3 more
Aims: We study the timing and spectral properties of the intermediate polar MU Camelopardalis (1RXS J062518.2+733433) to determine the accretion modes and the accretion geometry from multi-wavelength, multi-epoch observational data.
Methods: Light curves in different observed energy ranges (optical, UV, X-ray) are extracted. The timescales of …
The polyhedral nature of LINERs: an XMM-Newton view of LINERs in radio galaxies
Tavecchio, F.; Foschini, L.; Gliozzi, M. +1 more
Aims:We investigate the origin of X-rays and the nature of accretion flow in 4 low-ionization nuclear emission-line regions (LINERs) hosted by radio galaxies, namely NGC 1692, PKS 0625-35, 3C 88, 3C 444, recently observed with XMM-Newton.
Methods: We combine the results from the time-averaged spectral analysis with model-independent informatio…