Search Publications
On the determination of energy spectra of MeV electrons by the Ulysses COSPIN/KET
Fichtner, H.; Ferreira, S. E. S.; Heber, B. +1 more
The Ulysses mission has provided a wealth of data, particularly regarding the transport of low-energy cosmic ray electrons. These data have been used to derive significant constraints for the anisotropic spatial diffusion of these particles. Detailed model simulations allowed, in addition, to determine the relative contributions of galactic and Jo…
BS Indi: An enigmatic object in the Tucana association
Guenther, E. W.; Alcalá, J. M.; Esposito, M. +2 more
BS Ind (=HD 202947) is a young K0V star in the Tucana association. Photometric observations with the Hipparcos satellite show an eclipse-like light-curve with primary and secondary eclipse. The eclipsing binary has a period of 0.435338 days and a circular orbit. Our spectroscopic observations however show that the K0V primary is a single-line spec…
Spacecraft potential control for Double Star
Escoubet, C. P.; Baumjohann, W.; Zhao, H. +12 more
The spacecraft potential of Double Star TC-1 is positive in large parts of the orbits due to the photo-effect from solar EUV irradiation. These positive potentials typically disturb low energy plasma measurements on board. The potential can be reduced, and thereby the particle measurements improved, by emitting a positive ion beam. This method has…
Thermal response of Iapetus to an eclipse by Saturn's rings
Nicholson, P. D.; Matthews, K.; Soifer, B. T. +3 more
Measurements of Iapetus as seen at 20 and 2.2 µm in the shadow of Saturn's ring are given, providing the thermal response to a rapidly varying heat input. The 20 µm thermal emission follows the 2.2 µm flux input closely. The observations, plus a simple diffusion calculation, imply that the surface of Iapetus is made of material h…
Lessons from the GOODS [review article]
Giavalisco, Mauro
The Great Observatories Origins Deep Survey (GOODS) is a multi-facility project that combines data from NASA's Hubble, Chandra and Spitzer space telescopes with spectroscopy and ancillary optical and near-IR imaging from the ground (VLT, Keck, Gemini, Subaru, NOAO) to provide a database for studying galaxy and AGN evolution up to redshifts z ∼ 6.5…
Possible Optical Detection of the Anomalous X-Ray Pulsar CXOU J010043.1-721134
Durant, Martin; van Kerkwijk, Marten H.
Archival Hubble Space Telescope Wide Field Planetary Camera 2 observations of the Small Magellanic Cloud have serendipitously revealed a possible counterpart to the anomalous X-ray pulsar CXOU J010043.1-721134. The candidate is faint, but its location and strange colors make it an interesting object. We estimate that the probability of such a dete…
UVCS/SOHO investigation of the interface between streamers and coronal holes
Romoli, M.; Spadaro, D.; Ventura, R. +1 more
We investigated the properties of the interface between streamers and coronal holes at low heliocentric distances, observing the extended solar corona in the North-West quadrant by UVCS/SOHO. We measured the line profiles of the H I Lyα and O VI resonance doublet and the visible linearly polarized radiance at heliocentric distances ranging from 1.…
Electron Acceleration in the Corona
Simnett, G. M.
The series of nine impulsive, highly collimated beams of near-relativistic electrons seen by ACE/EPAM on 26 and 27 June 2004 occurred at a quiet time with respect to solar flare and CME production. However, they were accompanied by decametric type III radio bursts observed by WIND/WAVES, which had progressively higher starting frequencies, suggest…
Coronal Element Comparison Observed by SOHO SUMER in the Quiet Southeast and Northwest Limb Regions at 1.04 Rsolar above the Solar Disk
Landi, E.; Feldman, U.; Widing, K. G.
The composition in an isothermal region at 1.04 Rsolar above a diffuse, quiet coronal region on the northwest limb is studied and compared with a similar region above the southeast limb analyzed by Warren in 1999. Elemental abundances relative to H in the corona are measured and normalized to the abundance ratios in the photosphere. The…
A statistical study on the correlations between plasma sheet and solar wind based on DSP explorations
Zhang, T. L.; Rème, H.; Liu, Z. X. +3 more
By using the data of two spacecraft, TC-1 and ACE (Advanced Composition Explorer), a statistical study on the correlations between plasma sheet and solar wind has been carried out. The results obtained show that the plasma sheet at geocentric distances of about 9~13.4 Re has an apparent driving relationship with the solar wind. It is found that (1…