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XMM-Newton observations of the first unidentified TeV gamma-ray source TeV J2032+4130
Santangelo, A.; Horns, D.; Hoffmann, A. I. D. +2 more
Context: The first unidentified very high energy gamma ray source (TeV J2032+4130) in the Cygnus region has been the subject of intensive search for a counterpart source at other wavelengths. In particular, observations in radio and X-rays are important to trace a population of non-thermal electrons.
Aims: A deep (≈50 ks) exposure of TeV J2032…
Enceladus: Cassini observations and implications for the search for life
Hansen, C. J.; Tinetti, G.; Hartman, H. +5 more
Aims:The recent Cassini discovery of water vapor plumes ejected from the south pole of the Saturnian satellite, Enceladus, presents a unique window of opportunity for the detection of extant life in our solar system.
Methods: With its significant geothermal energy source propelling these plumes >80 km from the surface of the moon and the en…
Magnetic fields and gas in the cluster-influenced spiral galaxy NGC 4254. I. Radio and X-rays observations
Ehle, M.; Beck, R.; Chyży, K. T.
Aims:Radio observations can show how cluster galaxies are affected by various environmental factors, that perturb their morphology, as well as modify properties of the interstellar medium (ISM), especially the characteristics of its magnetic field.
Methods: We made high-resolution and high-sensitivity radio-polarimetric VLA observations of NGC…
A Wolf-Rayet/black-hole X-ray binary candidate in NGC 300
Schirmer, M.; Ehle, M.; Wilms, J. +2 more
Context: Wolf Rayet/black hole binaries are believed to exist as a later evolutionary product of high-mass X-ray binaries. Hundreds of such binaries may exist in galaxies, but only a few of them are close enough to be observed as X-ray binaries. Only a couple of candidates have been reported so far.
Aims: Based on XMM-Newton observations, we r…
The relative timing of supra-arcade downflows in solar flares
Fletcher, L.; Bain, H. M.; Khan, J. I.
Context: Supra-arcade downflows (generally dark, sunward-propagating features located above the bright arcade of loops in some solar flares) have been reported mostly during the decay phase, although some have also been reported during the rise phase of solar flares.
Aims: We investigate, from a statistical point of view, the timing of supra-a…
Velocities and divergences as a function of supergranule size
Roudier, Th.; Meunier, N.; Rieutord, M. +1 more
Context: The origin of supergranulation is not understood yet and many scenarios, which range from large-scale deep convection to large-scale instabilities of surface granular flows, are possible.
Aims: We characterize the velocities and divergences in supergranulation cells as a function of their size.
Methods: Using local correlation tra…
The stellar content of the XMM-Newton bright serendipitous survey
Braito, V.; Micela, G.; Favata, F. +5 more
Context: The comparison of observed counts in a given sky direction with predictions by Galactic models yields constraints on the spatial distribution and the stellar birthrate of young stellar populations. The XMM-Newton Bright Serendipitous Survey (XBSS) is an unbiased survey that includes a total of 58 stellar sources selected in the 0.5-4.5 ke…
Results from Droxo. I. The variability of fluorescent Fe 6.4 keV emission in the young star Elias 29. High-energy electrons in the star's accretion tubes?
Micela, G.; Favata, F.; Giardino, G. +3 more
Aims:We study the variability of the Fe 6.4 keV emission line from the Class I young stellar object Elias 29 in the ρ Oph cloud.
Methods: We analysed the data from Elias 29 collected by XMM-Newton during a nine-day, nearly continuous observation of the ρ Oph star-forming region (the Deep Rho-Oph X-ray Observation, named droxo). The data were s…
A photometric study of Be stars located in the seismology fields of COROT
Garrido, R.; Floquet, M.; Gutiérrez-Soto, J. +4 more
Context: In preparation for the COROT mission, an exhaustive photometric study of Be stars located in the seismology fields of the mission has been performed. The very precise and long-time-spanned photometric observations gathered by the COROT satellite will give important clues on the origin of the Be phenomenon.
Aims: The aim of this work i…
Observation of enhanced X-ray emission from the CTTS AA Tauri during one transit of an accretion funnel flow
Zapatero Osorio, M. R.; Grosso, N.; Bouvier, J. +3 more
Context: Classical T Tauri stars are young solar-type stars accreting material from their circumstellar disks. Thanks to a favorable inclination of the system, the classical T Tauri star AA Tau exhibits periodic optical eclipses as the warped inner disk edge occults the stellar photosphere.
Aims: We intend to observe the X-ray and UV emission …