Search Publications
An Ultracompact X-Ray Binary in the Globular Cluster NGC 1851
Maccarone, T. J.; Knigge, C.; Long, K. S. +2 more
We present far-ultraviolet photometry obtained with the Hubble Space Telescope of the low-mass X-ray binary 4U 0513-40 in the globular cluster NGC 1851. Our observations reveal a clear, roughly sinusoidal periodic signal with P sime 17 minutes and amplitude 3%-10%. The signal appears fully coherent and can be modeled as a simple reprocessing effec…
Northward field excursions in Saturn's magnetotail and their relationship to magnetospheric periodicities
Wilson, R. J.; Jackman, C. M.; McAndrews, H. J. +2 more
We present results from an investigation of Cassini encounters with Saturn's magnetotail current sheet, using magnetic field and plasma data. In the first of two intervals shown, small periodic changes in the north-south component of the magnetic field are matched by periodic density enhancements associated with the plasma sheet center. In the sec…
Regional differences in gully occurrence on Mars: A comparison between the Hale and Bond craters
Hiesinger, H.; Hauber, E.; Reiss, D. +1 more
The observation of gullies on Mars raised questions about the presence of liquid water in the recent past. In some regions like Hale and Bond crater, gullies occur in one crater (Hale) but do not in another crater nearby (Bond). These regional differences have been interpreted as an argument for a formation of the gullies related to groundwater. T…
Solar Coronal Structure and Stray Light in TRACE
DeForest, C. E.; Wills-Davey, M. J.; Martens, P. C. H.
Using the 2004 Venus transit of the Sun to constrain a semiempirical point-spread function (PSF) for the TRACE EUV solar telescope, we have measured the effect of stray light in that telescope. We find that 43% of 171 Å EUV light that enters TRACE is scattered, either through diffraction off the entrance filter grid or through other nonspecular ef…
The young stellar population of IC 1613. I. A new catalogue of OB associations
Herrero, A.; Monelli, M.; Corral, L. J. +4 more
Context: Determining the parameters of massive stars is crucial to understand many processes in galaxies and the Universe, since these objects are important sources of ionization, chemical enrichment and momentum. 10m class telescopes enable us to perform detailed quantitative spectroscopic analyses of massive stars in other galaxies, sampling are…
New insights on Titan's plasma-driven Schumann resonance inferred from Huygens and Cassini data
Sotin, C.; Kurth, W. S.; Berthelier, J. J. +8 more
After a preliminary analysis of the low-frequency data collected with the electric antenna of the Permittivity, Wave and Altimetry (PWA) experiment onboard the Huygens Probe that landed on Titan on 14 January, 2005, it was anticipated in a previous article [Béghin et al., 2007. A Schumann-like resonance on Titan driven by Saturn's magnetosphere po…
Large-Scale Flows in Prominence Cavities
Brooks, D. H.; Reeves, K. K.; Gibson, S. E. +5 more
Regions of rarefied density often form cavities above quiescent prominences. We observed two different cavities with the Coronal Multichannel Polarimeter on 2005 April 21 and with Hinode/EIS on 2008 November 8. Inside both of these cavities, we find coherent velocity structures based on spectral Doppler shifts. These flows have speeds of 5-10 km s…
Discovery of an eccentric 30 day period in the supergiant X-ray binary SAX J1818.6-1703 with INTEGRAL
Chaty, S.; Zurita Heras, J. A.
Context: SAX J1818.6-1703 is a flaring transient X-ray source serendipitously discovered by BeppoSAX in 1998 during an observation of the Galactic centre. The source was identified as a high-mass X-ray binary with an OB supergiant companion (SGXB). Displaying short and bright flares and an unusually very low quiescent level implying an intensity d…
First simultaneous measurements of waves generated at the bow shock in the solar wind, the magnetosphere and on the ground
Lucek, E. A.; Yeoman, T. K.; Fear, R. C. +3 more
On 5 September 2002 the Geotail satellite observed the cone angle of the Interplanetary Magnetic Field (IMF) change to values below 30° during a 56 min interval between 18:14 and 19:10 UT. This triggered the generation of upstream waves at the bow shock, 13 RE downstream of the position of Geotail. Upstream generated waves were subseque…
Comparison of STEREO/EUVI Loops with Potential Magnetic Field Models
Aschwanden, M. J.; Alexander, D.; DeRosa, M. L. +2 more
The Solar Terrestrial Relations Observatory (STEREO) provides the first opportunity to triangulate the three-dimensional coordinates of active region loops simultaneously from two different vantage points in space. Three-dimensional coordinates of the coronal magnetic field have been calculated with theoretical magnetic field models for decades, b…