Search Results - (Author, Cooperation:R. C. Elphic)
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1Latest Papers from Table of Contents or Articles in PressD. J. Lawrence ; V. R. Eke ; R. C. Elphic ; W. C. Feldman ; H. O. Funsten ; T. H. Prettyman ; L. F. Teodoro
American Association for the Advancement of Science (AAAS)
Published 2011Staff ViewPublication Date: 2011-11-26Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: *MoonPublished by: -
2Articles: DFG German National LicensesBame, S. J. ; McComas, D. J. ; Thomsen, M. F. ; Barraclough, B. L. ; Elphic, R. C. ; Glore, J. P. ; Gosling, J. T. ; Chavez, J. C. ; Evans, E. P. ; Wymer, F. J.
[S.l.] : American Institute of Physics (AIP)
Published 1993Staff ViewISSN: 1089-7623Source: AIP Digital ArchiveTopics: PhysicsElectrical Engineering, Measurement and Control TechnologyNotes: A light-weight, low-power, plasma analyzer is described that can be used for measuring the plasma environments of spacecraft with constrained resources. A unique system using a single electrostatic analyzer coupled to a single array of channel electron multipliers allows measurement of the three-dimensional energy per charge distributions of both ions and electrons over E/q ranges from ∼1 eV/q to (approximately-greater-than)40 keV/q. Particles selected by the analyzer are post-accelerated into the multipliers to maintain sensitivity for the lowest energy particles. An instrument using this concept called the magnetospheric plasma analyzer (MPA) is described. Presently, three MPAs are in geosynchronous orbits (GEO) aboard spacecraft with International Designators of 1989-046, 1990-095, and 1991-080. The MPA and its response characteristics are described, and examples of on-orbit data showing some of the MPA capabilities are presented.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] The orbit of the Pioneer Venus spacecraft is inclined at 105 to the ecliptic plane with periapsis at a latitude of 17N and at an altitude of 150 km. This orbital geometry provides shock crossings principally at solar zenith angles of greater than 60. Figure 1 shows several recent shock crossings ...Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] Fig. 1 Magnetic field enhancements observed within the ionosphere shortly after periapsis (at 1431.56) on orbit 3 of Pioneer Venus. Before and after this interval, the characteristic ionospheric field strength is less than 10 nT, while the peak field just outside the ionopause is -55 nT. Fig. 2 a, ...Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesPaschmann, G. ; Sonnerup, B. U. Ö. ; Papamastorakis, I. ; Sckopke, N. ; Haerendel, G. ; Bame, S. J. ; Asbridge, J. R. ; Gosling, J. T. ; Russell, C. T. ; Elphic, R. C.
[s.l.] : Nature Publishing Group
Published 1979Staff ViewISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] A characteristic of magnetic field reconnection is the acceleration of plasma as it flows across a rotational discontinuity. At the Earth's magnetopause this effect has only been observed recently during a few magnetopause crossings by the ISEE satellites. For one example analysed in detail ...Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesRussell, C. T. ; Luhmann, J. G. ; Barnes, A. ; Mihalov, J. D. ; Elphic, R. C.
[s.l.] : Nature Publishing Group
Published 1983Staff ViewISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] Figure 1 shows the magnetic field observed by Pioneer Venus over a 24-h period on 10 and 11 February 1982. The data are displayed in solar ecliptic coordinates with the jc-axis pointing towards the Sun and the z-axis pointing towards the ecliptic pole. The lighter trace on these plots shows ISEE3 ...Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1572-9672Source: Springer Online Journal Archives 1860-2000Topics: PhysicsNotes: Abstract The magnetic field profiles across the magnetopause obtained by the ISEE-1 and -2 spacecraft separated by only a few hundred kilometers are examined for four passes. During one of these passes the magnetosheath field was northward, during one it was slightly southward, and in two it was strongly southward. The velocity of the magnetopause is found to be highly irregular ranging from 4 to over 40 km s-1 and varying in less time than it takes for a spacecraft to cross the boundary. Thicknesses ranged from 500 to over 1000 km. Clear evidence for reconnection is found in the data when the magnetosheath field is southward. However, this evidence is not in the form of classic rotational discontinuity signatures. Rather, it is in the form of flux transfer events, in which reconnection starts and stops in a matter of minutes or less, resulting in the ripping off of flux tubes from the magnetosphere. Evidence for flux transfer events can be found both in the magnetosheath and the outer magnetosphere due to their alteration of the boundary normal. In particular, their presence at the time of magnetopause crossings invalidates the usual 2-dimensional analysis of magnetopause structure. Not only are these flux transfer events probably the dominant means of reconnection on the magnetopause, but they may also serve as an important source of magnetopause oscillations, and hence of pulsations in the outer magnetosphere. On two days the flux transfer rate was estimated to be of the order of 2 × 1012 Maxwells per second by the flux transfer events detected at ISEE. Events not detectable at ISEE and continued reconnection after passage of an FTE past ISEE could have resulted in an even greater reconnection rate at these times.Type of Medium: Electronic ResourceURL: