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The Computed Infrared Spectra of a Variety of [FePAH]+ Complexes: Mid- and Far-Infrared Features
Joblin, C.; Simon, A.
The effects of the π-coordination of an Fe atom on the mid- and far-infrared spectra of a mixture of cationic polycyclic aromatic hydrocarbons (PAHs), e.g., pyrene (C16H10), anthanthrene (C22H12), coronene (C24H12), ovalene (C32H14), circumpyrene (C42
Interplanetary Scintillation Observations of Stream Interaction Regions in the Solar Wind
Breen, A. R.; Bisi, M. M.; Fallows, R. A. +1 more
We present a summary of results from ten years of interplanetary scintillation (IPS) observations of stream interaction regions (SIRs) in the solar wind. Previous studies had shown that SIRs were characterized by intermediate-velocity solar wind and - in the case of compressive interactions - higher levels of scintillation. In this study we consid…
Combined Analysis of Images and Spectral Energy Distributions of Taurus Protostars
Whitney, Barbara A.; Gramajo, Luciana V.; Gómez, Mercedes +1 more
We present an analysis of spectral energy distributions (SEDs), near- and mid-infrared images, and Spitzer spectra of eight embedded Class I/II objects in the Taurus-Auriga molecular cloud. The initial model for each source was chosen using the grid of young stellar objects (YSOs) and SED fitting tool of Robitaille et al. Then the models were refi…
The Exotic Eclipsing Nucleus of the Ring Planetary Nebula SuWt 2
Bond, Howard E.; Stassun, Keivan G.; Maxted, P. F. L. +3 more
SuWt 2 is a planetary nebula (PN) consisting of a bright ionized thin ring seen nearly edge-on, with much fainter bipolar lobes extending perpendicularly to the ring. It has a bright (12th magnitude) central star, too cool to ionize the PN, which we discovered in the early 1990s to be an eclipsing binary. Although it was anticipated that there wou…
Θ1 Orionis C - A triple system?
Bychkov, V.; Lehmann, H.; Vitrichenko, E. +2 more
Context. As the brightest star in the Trapezium cluster, Θ1 Ori C is the youngest and nearest to us among O-stars. It is considered to be a multiple system where the main component is an oblique magnetic rotator.
Aims: Here, we aim at explaining the structure of the Θ1 Ori C system. We check for a new hypothesis about th…
Expanding atmosphere models for SSS spectra of novae
Ness, J. -U.; van Rossum, D. R.
Super Soft Source (SSS) spectra are powered by nuclear burning on the surface of a white dwarf. The released energy causes a radiatively-driven wind that leads to a radially extended atmosphere around the white dwarf. Significant blue shifts in photospheric absorption lines are found in the spectra of novae during their SSS phase, being an evidenc…
3D structure of the Gusev Crater region
Neukum, Gerhard; Foing, Bernard; Kneissl, Thomas +3 more
Gusev Crater lies within the Aeolis Quadrangle of Mars at the boundary between the northern lowlands and southern highlands. The ancient valley Ma'adim Vallis dissects the highlands south of Gusev Crater and is thought to have fed the crater with sediments. High Resolution Stereo Camera data and Digital Elevation Models were used to construct a ge…
Observational evidence for expansion in the SSS spectra of novae
Ness, J. -U.
For several novae, a bright X-ray source with a spectrum resembling the class of Super Soft X-ray Sources (SSS) has been observed a few weeks to months after outburst. Novae are powered by explosive nuclear burning on the surface of a white dwarf, and enough energy is produced to power a radiatively driven wind. Owing to the evolution of the opaci…
Stochastic orbital migration of small bodies in Saturn's rings
Papaloizou, J. C. B.; Rein, H.
Many small moonlets that create propeller structures have been found in Saturn's rings by the Cassini spacecraft. We study the dynamical evolution of such 20-50 m sized bodies, which are embedded in Saturn's rings. We estimate the importance of various interaction processes with the ring particles on the moonlet's eccentricity and semi-major axis …
Millimeter and submillimeter measurements of asteroid (2867) Steins during the Rosetta fly-by
Davidsson, B.; Hartogh, P.; Lellouch, E. +18 more
The European Space Agency Rosetta Spacecraft passed within 803 km of the main belt asteroid (2867) Steins on 5 September 2008. The Rosetta Spacecraft carries a number of scientific instruments including a millimeter and submillimeter radiometer and spectrometer. The instrument, named MIRO (Microwave Instrument for the Rosetta Orbiter), consists of…