--------------------------------------------------------- NSSDC Master Catalog Display Experiment --------------------------------------------------------- Quadrispherical Plasma Analyzer NSSDC ID: 73-019A-13 Mission Name: Pioneer 11 Principal Investigator: Barnes Description The instrument consisted of dual 90-deg quadrispherical electrostatic analyzers, one with 26 individual particle detectors and the other with 5 current collectors. The system was capable of measuring incident plasma distribution parameters over the energy range 0.1 to 18 keV for protons and approximately 1 to 500 eV for electrons. The high-resolution analyzer with a constant of 9 keV/Q per kV applied to the plates, had a mean plate radius of 9 cm and separation of 0.5 cm. This analyzer was used to measure ions only, and had 26 channeltrons mounted on the semicircular exit to the analyzer. The aperture pointed through a wide slit in the back of the spacecraft high-gain antenna reflector and pointed along the spin axis toward the earth (and therefore the sun). The edges of the antenna reflector limited the viewing of the instrument to 73 deg with respect to the spin axis. The channeltrons covered a range of plus or minus 51 deg. Each channeltron near the center covered 3 deg and approximately 8 deg near the edges of the analyzer. The angular width perpendicular to the long angular width was about 2 deg. In half the spin period the whole cone of half-angle 51 deg centered on the sun was swept out. A medium-energy analyzer with a mean radius of 12 cm and a 1-cm plate separation (constant of 6 keV/Q per kV applied) was used to detect both ions and electrons. The detectors were five flat-surface current collectors. The three center collectors each covered 15 deg and covered the angular range of plus or minus 22.5 deg from the spin axis. The two outside collectors had an angular width of 47.5 deg and were located at plus or minus 46.25 deg from the center of the analyzer. There was a variety of possible operating modes for the experiment; however, the principal mode utilized during the encounter phase was one in which the analyzer plate potential was stepped through its range every one-half revolution of the spacecraft, and all current collectors or channeltrons were read out at the peak flux roll angle. The high and medium resolution analyzers operated independently, so a cross check between these analyzers was possible. The dynamic range for the particle fluxes was from 1.0E+2 to 3.0E+9/(sq cm-s) and the proton temperature down to 2.0E+3 deg K could be ascertained. Data include the interplanetary region. Detector A was turned off on September 16, 1987. ------------------- Discipline(s) Planetary Science/Fields and Particles Space Physics/Heliospheric Studies --------------------------------------------------------- NSSDC Master Catalog Display Experiment Personnel --------------------------------------------------------- Quadrispherical Plasma Analyzer NSSDC ID: 73-019A-13 Principal Investigator Dr. Aaron Barnes Mail Stop 245-3 NASA Ames Research Center Moffett Field, CA 94035 Electronic Mail GAL::BARNES (NSI/DECNET) ----- Other Investigator Dr. Frederick L. Scarf (deceased) ----- Prof. Devrie S. Intriligator Carmel Research Center PO Box 1732 Santa Monica, CA 90406 ----- Prof. Louis A. Frank Department of Physics and Astronomy University of Iowa Iowa City, IA 52242 Electronic Mail FRANK@IOWASP.PHYSICS.UIOWA.EDU (INTERNET) IOWASP::FRANK (NSI/DECNET) ----- Prof. Reimar Luest Inst fur Extraterrestrische Physik Max-Planck-Institut fur Physik und Astrophysik 85748 Garching Germany ----- Mr. Harold R. Collard Mail Stop 245-6 NASA Ames Research Center Moffett Field, CA 94035 ----- Mr. Darrell D. McKibbin Mail Stop 245-6 NASA Ames Research Center Moffett Field, CA 94035 ----- Mr. V. T. Zavientseff Address Unknown ----- Dr. Zdenka K. Smith NOAA Space Environment Laboratory R/E/SE3 325 Broadway Boulder, CO 80303 Electronic Mail ZSMITH@NISTCS2 (BITNET) SELVAX::ZSMITH (NSI/DECNET) ----- Dr. William C. Feldman Mail Stop D438 Los Alamos National Laboratory PO Box 1663 Los Alamos, NM 87545 Electronic Mail ESSDP1::079275 (NSI/DECNET) ----- NSSDC Contact Dr. John F. Cooper GSFC-Code 632 Electronic Mail JCOOPER@NSSDCA.GSFC.NASA.GOV (INTERNET) NCF::JCOOPER (NSI/DECNET) ----- --------------------------------------------------------- NSSDC Master Catalog Display Experiment Selected References --------------------------------------------------------- Quadrispherical Plasma Analyzer NSSDC ID: 73-019A-13 1. Wolfe, J. H., Pioneer 10 observations of the solar wind interaction with Jupiter, Inpro. 121174, N74-26270. --------------------------------------------------------------------------- For questions about this experiment, please contact: Dr. John F. Cooper, jcooper@nssdca.gsfc.nasa.gov, (301)286-1193 GSFC-Code 632 [Logo] For questions about the NSSDC's information systems, please contact: Dr. James Thieman, thieman@nssdca.gsfc.nasa.gov, (301)286-9790 National Space Science Data Center, Code 633.2 NASA/Goddard Space Flight Center, Greenbelt, MD 20771 --------------------------------------------------------------------------- NASA Official: J. H. King, king@nssdca.gsfc.nasa.gov Last Updated: 1995-08-25 Output Generated: 1996-09-24 Programming by: E. V. Bell, II