Search Publications
Structures induced by small moonlets in Saturn's rings: Implications for the Cassini Mission
Seiß, M.; Spahn, F.; Sremčević, M. +1 more
Particle simulations are carried out to study density features caused by small moonlets embedded in a dense planetary ring. The creation of a ``propeller'' like structure is found together with adjacent density wakes. Both features are clear indications for the existence of moonlets in the rings. We confirmed that the propeller scales with the Hil…
The connection between ultraviolet and X-ray outflows in active galactic nuclei: the case of PDS 456
Simpson, Chris; O'Brien, Paul T.; Reeves, James N. +1 more
High-velocity outflows from active galactic nuclei are a well-known phenomenon in terms of the broad absorption lines seen in the ultraviolet/optical. More recently, similar, possibly related, outflows have been reported in the X-ray. The most extreme example is seen in the nearby, luminous QSO PDS 456, which displays a massive, high-velocity (500…
XMM-Newton View of the Ultraluminous X-Ray Sources in M51
Dewangan, Gulab C.; Griffiths, Richard E.; Miyaji, Takamitsu +2 more
We present results based on XMM-Newton observations of the nearby spiral galaxy M51 (NGC 5194 and NGC 5195). We confirm the presence of the seven known ultraluminous X-ray sources (ULXs) with luminosities exceeding the Eddington luminosity for a 10 Msolar black hole, a low-luminosity active galactic nucleus (LLAGN) with 2-10 keV luminos…
Spatially resolved spectroscopy of the E+A galaxies in the z= 0.32 cluster AC 114
Kuntschner, Harald; Bekki, Kenji; Colless, Matthew +5 more
We present spatially resolved intermediate-resolution spectroscopy of a sample of 12 E+A galaxies in the z= 0.32 rich galaxy cluster AC 114, obtained with the FLAMES multi-integral field unit system on the Very Large Telescope (VLT) of the European Southern Observatory. Previous integrated spectroscopy of all these galaxies by Couch & Sharples…
A New Technique for Deriving Prominence Mass from SOHO/EIT Fe XII (19.5 Nanometers) Absorption Features
Gilbert, Holly R.; Holzer, Thomas E.; MacQueen, R. M.
It is presently unclear what role prominences play in the initiation and dynamics of coronal mass ejections (CMEs), although erupting prominences are strongly correlated with CMEs. The masses of prominences involved in CMEs are not generally measured, but the accurate determination of such masses may help in assessing the dynamical importance of p…
Are radio galaxies and quiescent galaxies different? Results from the analysis of HST brightness profiles
Capetti, A.; Morganti, R.; de Ruiter, H. R. +3 more
We present a study of the optical brightness profiles of early type galaxies, using a number of samples of radio galaxies and optically selected elliptical galaxies. For the radio galaxy samples - B2 of Fanaroff-Riley type I and 3C of Fanaroff-Riley type II - we determined a number of parameters that describe a "Nuker-law" profile, which were comp…
Evolution in the Cluster Early-Type Galaxy Size-Surface Brightness Relation at z~=1
Demarco, R.; Infante, L.; Zheng, W. +41 more
We investigate the evolution in the distribution of surface brightness, as a function of size, for elliptical and S0 galaxies in the two clusters RDCS J1252.9-2927 (z=1.237) and RX J0152.7-1357 (z=0.837). We use multicolor imaging with the Advanced Camera for Surveys on the Hubble Space Telescope to determine these sizes and surface brightnesses. …
Calibration of the Planetary Fourier Spectrometer short wavelength channel
Piccioni, G.; Grassi, D.; Moshkin, B. E. +18 more
The Planetary Fourier Spectrometer (PFS) experiment on board the Mars Express mission has two channels covering the 1.2-5.5 µm short wavelength channel (SWC) and the 5.5-45 µm (LWC). The SWC measures part of the thermal emission spectrum and the solar reflected spectrum of Mars between 1700 and 8200 cm -1 with a spectral res…
Coronal properties of G-type stars in different evolutionary phases
Pallavicini, R.; Peres, G.; Maggio, A. +1 more
We report on the analysis of XMM-Newton observations of three G-type stars in very different evolutionary phases: the weak-lined T Tauri star
X-Ray Spectroscopy of Candidate Ultracompact X-Ray Binaries
Chakrabarty, Deepto; Juett, Adrienne M.
We present high-resolution spectroscopy of the neutron star/low-mass X-ray binaries (LMXBs) 4U 1850-087 and 4U 0513-40 as part of our continuing study of known and candidate ultracompact binaries. The LMXB 4U 1850-087 is one of four systems in which we had previously inferred an unusual Ne/O ratio in the absorption along the line of sight, most li…