Search Publications
Profile of strong magnetic field By component in magnetotail current sheets
Petrukovich, A. A.; Zhang, T. L.; Lucek, E. +8 more
The strong magnetic field By component (in GSM coordinates) has been increasingly noticed to play an important role in the dynamics of tail current sheet (CS). The distribution profile of strong By components in the tail CS (i.e., those with guide field), however, is not well known. In the present work, by using the simultane…
Water vapor in Titan's stratosphere from Cassini CIRS far-infrared spectra
Lellouch, E.; Irwin, P. G. J.; Teanby, N. A. +12 more
Here we report the measurement of water vapor in Titan's stratosphere using the Cassini Composite Infrared Spectrometer (CIRS, Flasar, F.M. et al. [2004]. Space Sci. Rev. 115, 169-297). CIRS senses water emissions in the far infrared spectral region near 50 µm, which we have modeled using two independent radiative transfer codes (NEMESIS (Ir…
Bar pattern speed evolution over the last 7 Gyr
Aguerri, J. A. L.; Pérez, I.; Méndez-Abreu, J.
Context. The tumbling pattern of a bar is the main parameter characterising its dynamics. From numerical simulations, its evolution since bar formation is tightly linked to the dark halo in which the bar is formed through dynamical friction and angular momentum exchange. Observational measurements of the bar pattern speed with redshift can restric…
Pulsation spectrum of δ Scuti stars: the binary HD 50870 as seen with CoRoT and HARPS
Auvergne, M.; Amado, P. J.; Baudin, F. +14 more
Aims: We present the results obtained with the CoRoT satellite for HD 50870, a δ Sct star which was observed for 114.4 d. The aim of these observations was to evaluate the results obtained for HD 50844, the first δ Sct star monitored with CoRoT, on a longer time baseline.
Methods: The 307,570 CoRoT datapoints were analysed with different…
Interacting dark matter contribution to the galactic 511 keV gamma ray emission: constraining the morphology with INTEGRAL/SPI observations
Martin, Pierrick; Vincent, Aaron C.; Cline, James M.
We compare the full-sky morphology of the 511 keV gamma ray excess measured by the INTEGRAL/SPI experiment to predictions of models based on dark matter (DM) scatterings that produce low-energy positrons: either MeV-scale DM that annihilates directly into e+e- pairs, or heavy DM that inelastically scatters into an excited sta…
A Detailed Morpho-kinematic Model of the Eskimo, NGC 2392: A Unifying View with the Cat's Eye and Saturn Planetary Nebulae
López, J. A.; Steffen, W.; García-Díaz, Ma. T. +1 more
The three-dimensional and kinematic structure of the Eskimo nebula, NGC 2392, has been notoriously difficult to interpret in detail given its complex morphology, multiple kinematic components and its nearly pole-on orientation along the line of sight. We present a comprehensive, spatially resolved, high-resolution, long-slit spectroscopic mapping …
The Long-term X-Ray Variability of Broad Absorption Line Quasars
Bauer, F. E.; Brandt, W. N.; Garmire, G. P. +2 more
We analyze the long-term (rest-frame 3-30 yr) X-ray variability of 11 broad absorption line (BAL) quasars, mainly to constrain the variation properties of the X-ray absorbing shielding gas that is thought to play a critical role in BAL wind launching. Our BAL quasar sample has coverage with multiple X-ray observatories including Chandra, XMM-Newto…
The CH4 structure in Titan's upper atmosphere revisited
Strobel, D. F.; Galand, M.; Yelle, R. V. +4 more
In this study, we reanalyze the CH4 structure in Titan's upper atmosphere combining the Cassini Ion Neutral Mass Spectrometer (INMS) data from 32 flybys and incorporating several updates in the data reduction algorithms. We argue that based on our current knowledge of eddy mixing and neutral temperature, strong CH4 escape mus…
Analysis of disk-resolved OMEGA and CRISM spectral observations of Phobos and Deimos
Bibring, J. -P.; Arvidson, R. E.; Gondet, B. +8 more
Disk-resolved observations of Phobos acquired by OMEGA at a range of lighting and viewing geometries were fit with the Hapke photometric function to solve for the single particle phase function and single scattering albedos from 0.4 to 2.5 µm. Single scattering albedos were recovered from CRISM observations of Phobos using the OMEGA derived …
Systematic study of X-ray cavities in the brightest galaxy in the Draco constellation NGC 6338
David, L. P.; Pandge, M. B.; Patil, M. K. +1 more
We present results based on the systematic analysis of currently available Chandra archive data on the brightest galaxy in the Draco constellation, NGC 6338, in order to investigate the properties of the X-ray cavities. In the central ∼6 kpc, at least two, possibly three, X-ray cavities are evident. All these cavities are roughly of ellipsoidal sh…