HR: 0800h
AN: SH21B-0402 [Abstracts]
TI: A Detection of the Same Hot Plasma in the Corona - During a CME - and Later at Ulysses
AU: * Suess, S T
EM: Steven.T.Suess@nasa.gov
AF: NASA Marshall Space Flight Center, Natl. Space Science & Technology Ctr.,
Mail Stop SD50, Huntsville, AL 35812
United States
AU: Poletto, G
EM: poletto@arcetri.astro.it
AF: Arcetri Astrophysical Observatory, (Instituto Nazionale di Astrofisica),
Largo Enrico Fermi, 5, Florence, 50125
Italy
AU: Bemporad, A
EM: bempy76@arcetri.astro.it
AF: Dipartimento di Astronomia e Scienza dello Spazio, University of Florence,
Largo Enrico Fermi, 2, Florence, 50125
Italy
AB:
We show direct evidence for the same very hot plasma being
detected remotely from SOHO in the corona and subsequently,
{\it in situ}, at Ulysses in the solar wind. This is, to
our knowledge, the first time that such an unambiguous identification
has been made in the case of hot plasma.
This detection complements studies correlating other
plasma and field properties observed {\it in situ} to the properties
measured at the source in the corona. This observation takes
advantage of a SOHO-Sun-Ulysses quadrature, during which the Sun-Ulysses
included angle is $90^\circ$ and it is possible to observe {\it in situ}
with Ulysses instruments the same plasma that has previously been
remotely observed with SOHO instruments in the corona on the limb
of the Sun.
The identification builds on an existing base of separate SOHO and
interplanetary detections of hot plasma. SOHO/UVCS has found evidence
for very hot coronal plasma in current sheets in the aftermath of CMEs
(Ciaravella et al., 2002; Raymond et al., 2003; Ko et al., 2002)
in the [Fe XVIII] $\lambda$ 974 \AA\ line, implying a temperature on the
order of $6 \times 10^6$ K. This temperature is unusually high even for
active regions, but is compatible with the high temperature predicted in
current sheets. In the solar wind,
ACE data from early 1998 to middle 2000 revealed
high frozen-in Fe charge state (Fe$^{16+}$)in many cases to
be present in interplanetary plasma (Lepri et al., 2004). These
identifications were associated with ICMEs.
Ciaravella, A., Raymond, J. C.,
Li, J., Reiser, P., Gardner, L. D., Ko, Y.-K., & Fineschi, S. 2002,
Astrophys. J., 575, 1116
Ko, Y.-K., Raymond, J. C., Li, J., Ciaravella,
A., Michels, J., Fineschi, S., & Wu, R. 2002, Astrophys. J., 578, 979
Lepri, S. T., & Zurbuchen, T. H. 2004, J. Geophys. Res., 109(A1), A01112
Raymond, J. C., Ciaravella, A.,
Dobrzycka, D., Strachan, L., Ko, Y.-K., & Uzzo, M. 2003,
Astrophys. J., 597, 1106
DE: 7513 Coronal mass ejections
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2169 Sources of the solar wind
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting