Search Publications
Methane Gas Stabilizes Supercooled Ethane Droplets in Titan's Clouds
Wang, Chia C.; Signorell, Ruth; Kathrin Lang, E.
Strong evidence for ethane clouds in various regions of Titan's atmosphere has recently been found. Ethane is usually assumed to exist as ice particles in these clouds, although the possible role of liquid and supercooled liquid ethane droplets has been recognized. Here, we report on infrared spectroscopic measurements of ethane aerosols performed…
Mass Loss Processes in Titan's Upper Atmosphere
Johnson, R. E.; Sittler, E. C.; Smith, H. T. +4 more
Although Titan's atmospheric column density is about ten times that of the Earth's, its measured 15N/14N ratio suggests that considerable escape has occurred or that Titan's original material had a ratio closer to that of cometary materials. A number of active escape processes have been proposed: thermal escape, chemical-induced escape, slow hydro…
Rotation and magnetic activity of the Hertzsprung-gap giant 31 Comae
Strassmeier, K. G.; Weber, M.; Granzer, T. +12 more
Context. The single rapidly-rotating G0 giant 31 Comae has been a puzzle because of the absence of photometric variability despite its strong chromospheric and coronal emissions. As a Hertzsprung-gap giant, it is expected to be at the stage of rearranging its moment of inertia, hence likely also its dynamo action, which could possibly be linked wi…
Chandra Reveals Variable Multi-component X-ray Emission From FU Orionis
Skinner, Stephen L.; Güdel, Manuel; Briggs, Kevin R. +1 more
FU Orionis is the prototype of a class of eruptive young stars ("FUors") characterized by strong optical outbursts. We recently completed an exploratory survey of FUors using XMM-Newton to determine their X-ray properties, about which little was previously known. The prototype FU Ori and V1735 Cyg were detected. The X-ray spectrum of FU Ori was fo…
Relationship between CME Parameters and Large-Scale Structure of Solar Magnetic Fields
Ivanov, E. V.; Fainshtein, V. G.
In this work, we explore how the parameters of coronal mass ejections (CME) associated with eruptive prominences (EP) depend on their position relative to the coronal streamer belt (CSB) and coronal streamer chains (CSCs). We show that the CMEs whose axes are close to CSB propagate at lower mean speed than the CMEs observed in the vicinity of CSCs…
The Photospheric Energy and Helicity Budgets of the Flux-injection Hypothesis
Schuck, P. W.
The flux-injection hypothesis for driving coronal mass ejections (CMEs) requires the transport of substantial magnetic energy and helicity flux through the photosphere concomitant with the eruption. Under the magnetohydrodynamics approximation, these fluxes are produced by twisting magnetic field and/or flux emergence in the photosphere. A CME tra…
INTEGRAL deep observations of the Small Magellanic Cloud
Haberl, F.; Zezas, A.; Udalski, A. +12 more
Deep observations of the Small Magellanic Cloud (SMC) and region were carried out in the hard X-ray band by the INTEGRAL observatory in 2008-2009. The field of view of the instrument permitted simultaneous coverage of the entire SMC and the eastern end of the Magellanic Bridge. In total, INTEGRAL detected seven sources in the SMC and five in the M…
Wide band observations of the X-ray burster GS 1826-238
Titarchuk, L.; Farinelli, R.; Cocchi, M. +1 more
Context. GS 1826-238 is a well-studied X-ray bursting neutron star in a low mass binary system. Thermal Comptonisation by a hot electron cloud (kTe ~ 20 keV) is a widely accepted mechanism accounting for its high energy emission, while the nature of most of its soft X-ray output is not completely understood. A further low energy compone…
HerMES: SPIRE detection of high-redshift massive compact galaxies in GOODS-N field
Altieri, B.; Elbaz, D.; Pérez-Fournon, I. +47 more
We have analysed the rest-frame far-infrared properties of a sample of massive (M* > 1011Msolar) galaxies at 2 <~ z <~ 3 in the Great Observatories Origins Deep Survey-North (GOODS-N) field using the Spectral and Photometric Imaging Receiver (SPIRE) instrument aboard the Herschel Space Observatory. To cond…
The origin of the [C II] emission in the S140 photon-dominated regions. New insights from HIFI
Boulanger, F.; France, K.; Le Petit, F. +38 more
Using Herschel's HIFI instrument, we observe C ii along a cut through S140, as well as high-J transitions of CO and HCO+ at two positions on the cut, corresponding to the externally irradiated ionization front and the embedded massive star-forming core IRS1. The HIFI data were combined with available ground-based observations and modele…