Search Publications
Cluster observations of fast shocks in the magnetosheath launched as a tangential discontinuity with a pressure increase crossed the bow shock
Farrugia, C. J.; RèMe, H.; Dunlop, M. +6 more
The interaction of a tangential discontinuity (TD) and accompanying dynamic pressure increase with the Earth's bow shock launches a fast shock that travels ahead of the TD in the magnetosheath and carries a significant portion of the pressure change. In this event study, we use observations from the Cluster spacecraft and magnetohydrodynamic simul…
Cluster observations of near-Earth magnetospheric lobe plasma densities a statistical study
Haaland, S.; Lybekk, B.; Pedersen, A. +1 more
The Cluster-mission has enabled a study of the near-Earth magnetospheric lobes throughout the waning part of solar cycle 23. During the first seven years of the mission the satellites crossed this region of space regularly from about July to October. We have obtained new and more accurate plasma densities in this region based on spacecraft potenti…
Evolved Stars in the Core of the Massive Globular Cluster NGC 2419
Sandquist, Eric L.; Hess, Jordan M.
We present an analysis of optical and ultraviolet Hubble Space Telescope photometry for evolved stars in the core of the distant massive globular cluster NGC 2419. We characterize the horizontal branch (HB) population in detail including corrections for incompleteness on the long blue tail. The majority of the HB stars can be identified with two m…
The X-Ray-Emitting Components toward l = 111°: The Local Hot Bubble and Beyond
Kuntz, K. D.; Snowden, S. L.
We have obtained an XMM-Newton spectrum of the diffuse X-ray emission toward (l ,b) = (111.14°,1.11°) , a line of sight with a relatively simple distribution of absorbing clouds: >9 × 1019 cm-2 at R > 170 pc, a 6 × 1021 cm-2 molecular cloud at 2.5-3.3 kpc, and a total column of 1.2 × 1022
Tomographic Separation of Composite Spectra. XI. The Physical Properties of the Massive Close Binary HD 100213 (TU Muscae)
Gies, Douglas R.; Penny, Laura R.; Ouzts, Cynthia
We present the results of a Doppler tomographic reconstruction of the UV spectra of the double-lined, O binary HD 100213 based on observations made with the International Ultraviolet Explorer (IUE). We used cross-correlation methods to obtain radial velocities, confirm the orbital elements, estimate the UV flux ratio, and determine projected rotat…
Simulating anisotropic thermal conduction in supernova remnants - II. Implications for the interstellar medium
Howk, J. Christopher; Balsara, Dinshaw S.; Bendinelli, Anthony J. +2 more
We present a large number of 2.5D simulations of supernova remnants expanding into interstellar media having a range of densities, temperatures and magnetic field strengths. The simulations include equilibrium cooling and anisotropic, flux-limited thermal conduction along magnetic field lines. The volume of hot gas produced during the remnant's ev…
Infrared observations of Saturn's rings by Cassini CIRS : Phase angle and local time dependence
Altobelli, Nicolas; Spilker, Linda J.; Ferrari, Cecile +2 more
Since the Saturn orbit insertion (SOI) of the Cassini spacecraft, in July 2004, the Cassini Composite Infrared Spectrometer (CIRS) has obtained a large number of thermal infrared spectra of Saturn's rings. Over the two and a half years of observations to date, ring temperatures were retrieved for a large range of unique geometries, inaccessible fr…
Dependence of the open-closed field line boundary in Saturn's ionosphere on both the IMF and solar wind dynamic pressure: comparison with the UV auroral oval observed by the HST
Belenkaya, E. S.; Badman, S. V.; Cowley, S. W. H. +2 more
We model the open magnetic field region in Saturn's southern polar ionosphere during two compression regions observed by the Cassini spacecraft upstream of Saturn in January 2004, and compare these with the auroral ovals observed simultaneously in ultraviolet images obtained by the Hubble Space Telescope. The modelling employs the paraboloid model…
Heating Titan's upper atmosphere
de La Haye, V.; Waite, J. H.; Cravens, T. E. +3 more
A detailed analysis of the mechanisms heating Titan's neutral atmosphere is provided. Two primary sources of incoming energy, the solar photons and the energetic electrons from Saturn's magnetosphere, are taken into account. The processes studied include the excitation of atmospheric molecules by electron impact, suprathermal electron heating, and…
INTEGRAL long-term monitoring of the supergiant fast X-ray transient XTE J1739-302
Pottschmidt, K.; Reig, P.; Torrejón, J. M. +6 more
Context: In the past few years, a new class of high mass X-ray binaries (HMXRB) has been claimed to exist, the supergiant fast X-ray transients (SFXT). These are X-ray binary systems with a compact companion orbiting a supergiant star which show very short and bright outbursts in a series of activity periods overimposed on longer quiescent periods…