Search Publications
Thermally driven atmospheric escape: Monte Carlo simulations for Titan's atmosphere
Johnson, R. E.; Tucker, Orenthal J.
Recent models of Titan's upper atmosphere were used to reproduce the Cassini measurements of the density vs. altitude by allowing a net upward flow at the exobase. Large mass flow rates were extracted and interpreted due to thermally driven escape to space at a rate that is orders of magnitude larger than the Jeans escape rate. This process is ref…
X-ray spectra from magnetar candidates - III. Fitting SGR/AXP soft X-ray emission with non-relativistic Monte Carlo models
Rea, N.; Zane, S.; Nobili, L. +1 more
Within the magnetar scenario, the `twisted magnetosphere' model appears very promising in explaining the persistent X-ray emission from soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs). In the first two papers of the series, we have presented a 3D Monte Carlo code for solving radiation transport as soft, thermal photons emitted by th…
Hinode/XRT and STEREO Observations of a Diffuse Coronal "Wave"-Coronal Mass Ejection-Dimming Event
Testa, Paola; Attrill, Gemma D. R.; Engell, Alexander J. +2 more
We report on observations of the first diffuse coronal wave detected by Hinode/XRT. The event occurred near the west solar limb on 2007 May 23, originating from active region (AR) 10956 and was associated with a coronal mass ejection (CME) and coronal dimmings. The bright emission forming the coronal wave expanded predominantly to the east and sou…
Molecular gas in NUclei of GAlaxies (NUGA). XI. A complete gravity torque map of NGC 4579: new clues to bar evolution
Hunt, L. K.; Krips, M.; Schinnerer, E. +6 more
In this paper we create a complete gravity torque map of the disk of the LINER/Seyfert 1.9 galaxy NGC 4579. We quantify the efficiency of angular momentum transport and search for signatures of secular evolution in the fueling process from r ~ 15 kpc down to the inner r ~ 50 pc around the active galactic nucleus (AGN). We use both the 1-0 and 2-1 …
Characteristics of charged dust inferred from the Cassini RPWS measurements in the vicinity of Enceladus
Gurnett, D. A.; Kurth, W. S.; Wahlund, J. -E. +6 more
The data obtained by the Cassini Radio and Plasma Wave Science (RPWS) instrument during the shallow (17.02.2005) and the steep (14.07.2005) crossings of the E-ring revealed a considerable electron depletion in proximity to Enceladus's orbit (the difference between the ion and electron densities can reach ∼70cm-3). Assuming that this dep…
Updating the orbital ephemeris of Hercules X-1; rate of decay and eccentricity of the orbit
Klochkov, D.; Wilms, J.; Staubert, R.
We present an update of the orbital ephemeris of the binary X-ray pulsar Her X-1 and determine an improved value for the rate of orbital decay. In addition, we report the first measurement of the orbital eccentricity. We analyzed pulse timing data of Her X-1 from X-ray observations by RXTE (Rossi X-Ray Timing Explorer) and INTEGRAL over the period…
Ultradeep Near-Infrared Observations of Goods 850-5
Wang, Wei-Hao; Cowie, Lennox L.; Barger, Amy J.
GOODS 850-5 is a hyperluminous radio-faint submillimeter source in the Great Observatories Origins Deep Survey-North. Although it is generally agreed that GOODS 850-5 is at a high redshift, z gsim 4, its exact redshift is unknown. While its stellar spectral energy distribution (SED) suggests z ~ 6, its radio/far-IR (FIR) SED suggests a lower redsh…
Dayglow on Mars: Kinetic modelling with SPICAM UV limb data
Bertaux, J. -L.; Leblanc, F.; Witasse, O. +2 more
The UV spectrometer experiment SPICAM onboard ESA Mars Express has been orbiting Mars since December 2003. We present here some comparisons between airglow data that have been newly interpreted with the advanced kinetic model Trans-Mars. A series of numerical one-dimensional kinetic models, in the Trans-* family [Lilensten, J., Blelly. P.L., 2002.…
Equatorward diffuse auroral emissions at Jupiter: Simultaneous HST and Galileo observations
Krupp, N.; Woch, J.; Menietti, J. D. +6 more
We study the auroral emissions equatorward of the main oval based on Hubble Space Telescope (HST) observations of both Jovian hemispheres on September 20, 1997. On the same day, Galileo observed changes in the electron pitch angle distribution between the inner and middle magnetosphere (PAD boundary), indicative of electron diffusion. This region,…
Spitzer Observations of Extended Lyman-α Clouds in the SSA22 Field
Egami, E.; Yamada, T.; Matsuda, Y. +5 more
We present the results of a Spitzer IRAC and MIPS 24 µm study of extended Lyman-α clouds (or Lyman-α Blobs, LABs) within the SSA22 filamentary structure at z = 3.09. We detect 6/26 LABs in all IRAC filters, four of which are also detected at 24 µm, and find good correspondence with the 850 µm measurements of Geach et al. An analy…