Search Publications
Thermophysical property variations across Dione and Rhea
Spencer, J. R.; Howett, C. J. A.; Segura, M. +2 more
Maps of the variation in bolometric Bond albedo and thermal inertia across Rhea and Dione have been produced using various day and nighttime observations, taken by Cassini's Composite Infrared Spectrometer (CIRS). The albedo maps show the same trend that has been previously observed on these satellites from reflected sunlight and thermal observati…
Equilibrium composition between liquid and clathrate reservoirs on Titan
Sotin, Christophe; Mousis, Olivier; Choukroun, Mathieu +1 more
Hundreds of lakes and a few seas of liquid hydrocarbons have been observed by the Cassini spacecraft to cover the polar regions of Titan. A significant fraction of these lakes or seas could possibly be interconnected with subsurface liquid reservoirs of alkanes. In this paper, we investigate the interplay that would happen between a reservoir of l…
On the relation between metallicity and RGB color in HST/ACS data
de Jong, R. S.; Goudfrooij, P.; Bailin, J. +3 more
Context. The determination of stellar metallicity and its gradient in external galaxies is a difficult task, but crucial for the understanding of galaxy formation and evolution.
Aims: The color of the Red Giant Branch (RGB) can be used to determine metallicities of stellar populations that have only shallow photometry. We will quantify the re…
Evolution of electron pitch angle distributions across Saturn's middle magnetospheric region from MIMI/LEMMS
Livi, S.; Krupp, N.; Roussos, E. +5 more
We provide a global view of ~20 to 800 keV electron pitch angle distributions (PADs) close to Saturn's current sheet using observations from the Cassini MIMI/LEMMS instrument. Previous work indicated that the nature of pitch angle distributions in Saturn's inner to middle magnetosphere changes near the radial distance of 10RS. This work…
Numerical simulation of tides and oceanic angular momentum of Titan’s hydrocarbon seas
Lorenz, Ralph D.; Tokano, Tetsuya; Van Hoolst, Tim
Tides and tidal currents in Titan's hydrocarbon seas are numerically simulated by a 3-dimensional ocean circulation model using a bathymetry map constrained by Cassini. These predictions are used to calculate the tidally induced variations of the oceanic angular momentum of the seas. The tides behave as a quasi-standing wave with anti-nodes at the…
A survey of hot flow anomalies at Venus
Coates, A. J.; Fedorov, A.; Barabash, S. +10 more
We present the first survey of hot flow anomalies (HFAs) at the bow shock of Venus, expanding on our recent initial case study. A 3.06 sol (774 Earth day) survey of Venus Express magnetometer, ion spectrometer, and electron spectrometer data was undertaken in order to identify Cytherian HFAs. Seven events were discovered, corresponding to a statis…
The Mid-infrared Appearance of the Galactic Mini-starburst W49A
Peeters, E.; Stock, D. J.; Shannon, M. J. +1 more
The massive star-forming region W49A represents one of the largest complexes of massive star formation present in the Milky Way and contains at least 50 young massive stars still enshrouded in their natal molecular cloud. We employ Spitzer/Infrared Spectrometer spectral mapping observations of the northern part of W49A to investigate the mid-infra…
On the Puzzling High-Energy Pulsations of the Energetic Radio-Quiet γ-Ray Pulsar J1813-1246
Marelli, M.; Saz Parkinson, P. M.; Wood, K. S. +6 more
We have analyzed the new deep XMM-Newton and Chandra observations of the energetic, radio-quiet pulsar J1813-1246. The X-ray spectrum is nonthermal, very hard, and absorbed. Based on spectral considerations, we propose that J1813 is located at a distance further than 2.5 kpc. J1813 is highly pulsed in the X-ray domain, with a light curve character…
Low-luminosity X-ray sources and the Galactic ridge X-ray emission
Warwick, R. S.
Using the XMM-Newton slew survey, we construct a hard-band selected sample of low-luminosity Galactic X-ray sources. Two source populations are represented, namely coronally active stars and binaries (ASBs) and cataclysmic variables (CVs), with X-ray luminosities collectively spanning the range 1028-34 erg s-1 (2-10 keV). We …
Do the spectral energy distributions of type 1 active galactic nuclei show diversity?
Stewart, G. C.; Scott, A. E.
We create broad-band spectral energy distributions (SEDs) of 761 type 1 active galactic nuclei (AGN). The Scott et al. sample, created by a cross-correlation of the optical Sloan Digital Sky Survey Data Release 5 quasar catalogue and the 2XMMi catalogue of serendipitous X-ray sources, is further matched with the Faint Images of the Radio Sky at Tw…