Search Publications
Simultaneous XMM-Newton and HST-COS observation of 1H0419-577. The absorbing and emitting ionized gas
Kaastra, J. S.; Arav, N.; Edmonds, D. +7 more
In this paper we analyze the X-ray, UV, and optical data of the Seyfert 1.5 galaxy 1H0419-577 with the aim of detecting and studying an ionized-gas outflow. The source was observed simultaneously in the X-rays with XMM-Newton and in the UV with HST-COS. Optical data were also acquired with the XMM-Newton Optical Monitor. We detected a thin, lowly …
Local spectrophotometric properties of pyroclastic deposits at the Lavoisier lunar crater
Besse, S.; Josset, J. -L.; Haruyama, J. +5 more
We present a study of the Lavoisier lunar crater combining photometric data from the AMIE camera (SMART-1 mission) and hyperspectral data from the Moon Mineralogy Mapper M3 (Chandrayaan-1 mission), with a special emphasis on the pyroclastic deposits considered to be present on the crater floor. The photometric parameters are in agreemen…
Thermodynamic fluctuations in solar photospheric three-dimensional convection simulations and observations
Rezaei, R.; Puschmann, K. G.; Moreno-Insertis, F. +2 more
Context. Numerical three-dimensional (3D) radiative (magneto-)hydrodynamical [(M)HD] simulations of solar convection are nowadays used to understand the physical properties of the solar photosphere and convective envelope, and, in particular, to determine the Sun's photospheric chemical abundances. To validate this approach, it is important to che…
The Hyades Cluster: Identification of a Planetary System and Escaping White Dwarfs
Zuckerman, B.; Xu, S.; Klein, B. +1 more
Recently, some hot DA-type white dwarfs have been proposed to plausibly be escaping members of the Hyades. We used hydrogen Balmer lines to measure the radial velocities of seven such stars and confirm that three, and perhaps two others, are/were indeed cluster members and one is not. The other candidate Hyad is strongly magnetic and its membershi…
Formation of a White-Light Jet Within a Quadrupolar Magnetic Configuration
Filippov, Boris; Tavabi, Ehsan; Koutchmy, Serge
We analyze multi-wavelength and multi-viewpoint observations of a large-scale event viewed on 7 April 2011, originating from an active-region complex. The activity leads to a white-light jet being formed in the outer corona. The topology and evolution of the coronal structures were imaged in high resolution using the Atmospheric Imaging Assembly (…
Does ice float in Titan’s lakes and seas?
Lunine, Jonathan I.; Hofgartner, Jason D.
We model Titan’s lakes and seas as methane-ethane-nitrogen systems and model the buoyancy of solids in these systems assuming thermodynamic equilibrium. We find that ice will float in methane-rich lakes for all temperatures below the freezing point of pure methane and that ice will also float in ethane-rich seas provided the ice has an air porosit…
Cluster observations of whistler waves correlated with ion-scale magnetic structures during the 17 August 2003 substorm event
Sauvaud, J. -A.; Le Contel, O.; Fontaine, D. +4 more
We provide evidence of the simultaneous occurrence of large-amplitude, quasi-parallel whistler mode waves and ion-scale magnetic structures, which have been observed by the Cluster spacecraft in the plasma sheet at 17 Earth radii, during a substorm event. It is shown that the magnetic structures are characterized by both a magnetic field strength …
Absence of hot gas within the Wolf-Rayet bubble around WR 16
Guerrero, M. A.; Toalá, J. A.
We present the analysis of XMM-Newton archival observations towards the Wolf-Rayet (WR) bubble around WR 16. Despite the closed bubble morphology of this WR nebula, the XMM-Newton observations show no evidence of diffuse emission in its interior as in the similar WR bubbles NGC 6888 and S 308. We use the present observations to estimate a 3-σ uppe…
The Vast Population of Wolf-Rayet and Red Supergiant Stars in M101. I. Motivation and First Results
Drissen, Laurent; Moffat, Anthony F. J.; Shara, Michael M. +3 more
Assembling a catalog of at least 10,000 Wolf-Rayet (W-R) stars is an essential step in proving (or disproving) that these stars are the progenitors of Type Ib and Type Ic supernovae. To this end, we have used the Hubble Space Telescope (HST) to carry out a deep, He II optical narrowband imaging survey of the ScI spiral galaxy M101. Almost the enti…
XMM-Newton and Swift observations of XTE J1743-363
Campana, S.; Israel, G.; Stella, L. +5 more
XTE J1743-363 is a poorly known hard X-ray transient, which displays short and intense flares similar to those observed from supergiant fast X-ray transients. The probable optical counterpart shows spectral properties similar to those of an M8 III giant, thus suggesting that XTE J1743-363 belongs to the class of the symbiotic X-ray binaries class.…