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111.
M. van der Klis J.M. Bonnet-Bidaud 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Results are presented of an analysis of 83 days of 2–12 keV X-ray observations of Vela X-1 (4U 0900-40) obtained during three separate pointings with the ESA COS-B satellite. The pulsation period is shown to undergo very rapid intrinsic changes, at a rate of up to
during intervals of a few days. The lower values of
which were previously observed over longer intervals, appear to result from an averaging-out of these rapid changes. It is argued, that the transfer of angular momentum to the neutron star by the accreting matter is very unlikely to be sufficient to explain these pulsation-period changes. An alternative explanation is suggested. 相似文献
112.
113.
We present an introduction to four papers on further analysis of the raw Hipparcos data. This analysis has lead to the recognition
of how orbit, radiation and temperature conditions did or didn't affect the scientific results of the Hipparcos mission. It
also led the way to a new reduction of the scientific data that shows from its initial results a real potential for a substantial
improvement of the astrometric parameters for stars brighter than V=8.5. This short paper serves as an introduction to the four main papers, and provides some general references.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
114.
115.
K. Mukai J. M. Bonnet-Bidaut S. Bowyer P. A. Charles L. Chiappetti J. T. Clarke R. H. D. Corbet J. P. Henry G. J. Hill S. M. Kahn L. Maraschi J. Osborne A. Treves M. van der Klis J. van Paradijs S. D. Vrtilek 《Space Science Reviews》1985,40(1-2):151-155
The AM Her type object E2003+225 was observed with EXOSAT, IUE and ground-based telescopes on 1983 Oct. 12. The brightness of the ultrasoft X-ray component allowed the Objective Grating Spectrometer (OGS) to be used, which gave a model-independent determination of the temperature of the blackbody spectrum. The star was observed again on 1984 July 24 by IUE with simultaneous optical spectrophotometry. The high resolution of this observation revealed complex line profiles, and a systematic velocity much smaller than previously reported. The composite energy distribution is presented. 相似文献
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118.
Clinton J. Giardini D. Böse M. Ceylan S. van Driel M. Euchner F. Garcia R. F. Kedar S. Khan A. Stähler S. C. Banerdt B. Lognonne P. Beucler E. Daubar I. Drilleau M. Golombek M. Kawamura T. Knapmeyer M. Knapmeyer-Endrun B. Mimoun D. Mocquet A. Panning M. Perrin C. Teanby N. A. 《Space Science Reviews》2018,214(8):1-51
Space Science Reviews - In recent decades, volcanic and cryovolcanic activity on moons within the Solar System has been recognised as an important source of cosmic dust. Two moons, Jupiter’s... 相似文献
119.
L. van Driel-Gesztelyi C.P. Goff P. Démoulin J.L. Culhane S.A. Matthews L.K. Harra C.H. Mandrini K.-L. Klein H. Kurokawa 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
A series of three flares of GOES class M, M and C, and a CME were observed on 20 January 2004 occurring in close succession in NOAA 10540. Types II, III, and N radio bursts were associated. We use the combined observations from TRACE, EIT, Hα images from Kwasan Observatory, MDI magnetograms, GOES, and radio observations from Culgoora and Wind/ WAVES to understand the complex development of this event. We reach three main conclusions. First, we link the first two impulsive flares to tether-cutting reconnections and the launch of the CME. This complex observation shows that impulsive quadrupolar flares can be eruptive. Second, we relate the last of the flares, an LDE, to the relaxation phase following forced reconnections between the erupting flux rope and neighbouring magnetic field lines, when reconnection reverses and restores some of the pre-eruption magnetic connectivities. Finally, we show that reconnection with the magnetic structure of a previous CME launched about 8 h earlier injects electrons into open field lines having a local dip and apex (located at about six solar radii height). This is observed as an N-burst at decametre radio wavelengths. The dipped shape of these field lines is due to large-scale magnetic reconnection between expanding magnetic loops and open field lines of a neighbouring streamer. This particular situation explains why this is the first N-burst ever observed at long radio wavelengths. 相似文献
120.
We present an overview of how the principal physical properties of magnetic flux which emerges from the toroidal fields in the tachocline through the turbulent convection zone to the solar surface are linked to solar activity events, emphasizing the effects of magnetic field evolution and interaction with other magnetic structures on the latter. We compare the results of different approaches using various magnetic observables to evaluate the probability of flare and coronal mass ejection (CME) activity and forecast eruptive activity on the short term (i.e. days). Then, after a brief overview of the observed properties of CMEs and their theoretical models, we discuss the ejecta properties and describe some typical magnetic and composition characteristics of magnetic clouds (MCs) and interplanetary CMEs (ICMEs). We review some individual examples to clarify the link between eruptions from the Sun and the properties of the resulting ejecta. The importance of a synthetic approach to solar and interplanetary magnetic fields and activity is emphasized. 相似文献