Search Publications
Far ultraviolet spectroscopy of (non-magnetic) cataclysmic variables
Long, Knox S.
HST and FUSE have provided high signal-to-noise, high-resolution spectra of a variety of cataclysmic variables and have allowed a detailed characterization of FUV emission sources in both high and low states. Here, I describe how this has advanced our understanding of non-magnetic CVs. In the high state, the FUV spectra are dominated by disk emiss…
Plasma mixing as a cause of solar wind magnetic field variations
Balogh, A.; Facskó, G.; Erdős, G. +1 more
In the present paper, we have studied the effect of plasma mixing on the small-scale field configurations. We have employed theoretical models and numerical simulations to describe magnetic field structures formed by the mixing motion of the interplanetary plasma. The small-scale magnetic fluctuations share properties with waves and with turbulenc…
A systematic search of highly variable X-ray sources with the XMM-Newton serendipitous survey
Yuan, Weimin; Komossa, Stefanie; Osborne, Julian P. +1 more
We describe an ongoing programme to search for X-ray sources with long-term, large amplitude X-ray variability. The method is to compare the X-ray sources from the XMM-Newton Serendipitous Survey with those from the previous ROSAT pointed observations and the ROSAT All-sky Survey. The work is largely motivated by the recent discovery of a new type…
Two candidate homologous CMEs on 2002 May 22
Cheng, J. X.; Chen, P. F.; Fang, C.
Two coronal mass ejections (CMEs) occurred on 2002 May 22, originating from the same active region, AR 9948. Multi-wavelength data are collected in order to clarify the relationship between the CMEs, the associated flares and filament eruptions, and some other magnetic activities, which is of great importance to understand the mechanism of each ph…
XMM-Newton observations of low luminosity Be/X-ray candidates
Haberl, F.; Motch, C.; Janot-Pacheco, E. +2 more
A small number of early Be stars exhibit X-ray luminosities intermediate between those typical of early type stars and those radiated by Be/X-ray binaries in the quiescent state. We report on XMM-Newton observations of two such Be stars, HD 161103 and SAO 49725 which were originally discovered in a systematic cross-correlation between the ROSAT al…
FUV and X-ray grating spectra of novae and supersoft X-ray sources
Orio, M.
I review recent FUV and X-ray observations of classical and recurrent novae and supersoft X-ray sources, among them potential type Ia supernova progenitors. FUSE spectra show emission lines of O VI, which appear to be produced very close to the white dwarf of the binary system. In one case, these lines have allowed a measurement of the white dwarf…
Modelling the large particle environment of comet 67P/Churyumov Gerasimenko
Agarwal, J.; Grün, E.; Müller, M. +1 more
A method is presented to simulate images of a cometary dust trail in consistency with observed gas and dust production rates. It is also applicable to dust tails including neckline and antitail phenomena. Our main objective is to analyse the amount of mm-sized and larger particles within a given image. These are interesting to us because their emi…
Inferring the composition of the liquid surface on Titan at the Huygens probe landing site from Surface Science Package measurements
Lorenz, R. D.; Hagermann, A.; Leese, M. R. +5 more
With Huygens’ descent into Titan’s atmosphere drawing nearer, the composition and state of Titan’s surface remained largely unknown. The idea of a global ocean on Titan has become less popular over the last decade, though the possibility of lakes and seas has remained, and recently [Campbell, D.B., Black, G.J., Carter, L.M., Ostro, S.J. Radar evid…
The ultraluminous X-ray sources NGC 1313 X-1 and X-2
Falomo, R.; Treves, A.; Turolla, R. +3 more
We present a detailed analysis of XMM archival data of two Ultraluminous X-ray Sources (ULXs) in the nearby spiral galaxy NGC 1313: NGC 1313 X-1 and X-2. The spectral continuum of these sources was modeled with a soft thermal component plus a power-law. If the soft component originates from an accretion disk, the inferred mass of the compact remna…
The strands of the F ring disturbed by its closest satellites
Mourão, D. C.; Giuliatti Winter, S. M.; Freitas, T. C. A.
Some Voyager images showed that the F ring of Saturn is composed of at least four separate, non-intersecting, strands covering about 45° in longitude. According to Murray et al. [Murray, C.D., Gordon, M., Giuliatti Winter, S.M. Unraveling the strands of Saturn's F ring. Icarus 129, 304, 1997.] this structure may be caused by undetected satellites …