HR: 10:35h
AN: SH12A-02    [Abstracts]
TI: The GENESIS Solar-Wind Sample: Summary of In-Situ Spacecraft Measurements During the Sample Collection Period
AU: * Reisenfeld, D B
EM: dan.reisenfeld@umontana.edu
AF: University of Montana, Department of Physics & Astronomy 32 Campus Dr., Missoula, MT 59812 United States
AU: Steinberg, J T
EM: jsteinberg@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Sciences MS-D466, Los Alamos, NM 87545
AU: Wiens, R C
EM: rwiens@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Sciences MS-D466, Los Alamos, NM 87545
AU: Barraclough, B L
EM: bbarraclough@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Sciences MS-D466, Los Alamos, NM 87545
AU: Zurbuchen, T H
EM: thomasz@umich.edu
AF: University of Michigan, Dept AO & SS 2455 Hayward St, Ann Arbor, MI 48109 United States
AU: Burnett, D S
EM: burnett@gps.caltech.edu
AF: Caltech, Division of Geological and Planetary Sciences MS 100-23 1200 E. California Blvd., Pasadena, CA 91125 United States
AB: The GENESIS mission returned samples of solar wind to earth on September 8. These samples were collected between 30-Nov-2001 and 01-Apr-2004 at the L1 point on ultrapure substrates that are being analyzed using various laboratory techniques. The primary purpose of the GENESIS mission is to determine to unprecedented accuracy (e.g., $\pm$1%-0.1%, 2$\sigma$) the isotopic composition of the solar wind, and by extension, of the Sun, particularly for oxygen, nitrogen, carbon, and the noble gases. In addition to a continuously-collected sample, separate samples of the different regimes-coronal hole (CH), interstream (IS), and coronal mass ejection (CME)-were collected to help deconvolve any fine-scale isotopic fractionation associated with solar-wind ionization and acceleration. The four different samples (3 regimes plus one cumulative sample) are long-term averages over varying solar-wind conditions, and need to be understood within the context of other measurements besides those that can be made on the substrates themselves. These include charge state, v, T, density, and magnetic field data. Additionally, comparisons of in-situ elemental composition measurements with the measurements made on GENESIS samples will be useful in validating the different measurement techniques. For these reasons, we are compiling a database of conditions as measured by in-situ spacecraft instruments stationed at L1 over the time period of the GENESIS sample collection. Comparison with ACE/SWICS elemental and charge-state abundances confirmed early in the GENESIS mission that the GENESIS regime-selection algorithm was successfully isolating the CME material, protecting the CH and IS samples from CME contamination. The data also demonstrate the discrimination between IS and CH flow types based mostly on solar-wind speed, but allowing compensation for evolution effects due to the transit to 1 AU.
DE: 7594 Instruments and techniques
DE: 5455 Origin and evolution
DE: 2164 Solar wind plasma
DE: 2169 Sources of the solar wind
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting