Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - No evidence for heating of the solar wind at strong current sheets
AU - Borovsky, Joseph E.
AU - Denton, Michael H.
PY - 2011/10/1
Y1 - 2011/10/1
N2 - It has been conjectured that strong current sheets are the sites of proton heating in the solar wind. For the present study, a strong current sheet is defined by a >45 degrees rotation of the solar-wind magnetic-field direction in 128 s. A total of 194,070 strong current sheets at 1 AU are analyzed in the 1998-2010 ACE solar-wind data set. The proton temperature, proton specific entropy, and electron temperature at each current sheet are compared with the same quantities in the plasmas adjacent to the current sheet. Statistically, the plasma at the current sheets is not hotter or of higher entropy than the plasmas just outside the current sheets. This is taken as evidence that there is no significant localized heating of the solar-wind protons or electrons at strong current sheets. Current sheets are, however, found to be more prevalent in hotter solar-wind plasma. This is because more current sheets are counted in the fast solar wind than in the slow solar wind, and the fast solar wind is hotter than the slow solar wind.
AB - It has been conjectured that strong current sheets are the sites of proton heating in the solar wind. For the present study, a strong current sheet is defined by a >45 degrees rotation of the solar-wind magnetic-field direction in 128 s. A total of 194,070 strong current sheets at 1 AU are analyzed in the 1998-2010 ACE solar-wind data set. The proton temperature, proton specific entropy, and electron temperature at each current sheet are compared with the same quantities in the plasmas adjacent to the current sheet. Statistically, the plasma at the current sheets is not hotter or of higher entropy than the plasmas just outside the current sheets. This is taken as evidence that there is no significant localized heating of the solar-wind protons or electrons at strong current sheets. Current sheets are, however, found to be more prevalent in hotter solar-wind plasma. This is because more current sheets are counted in the fast solar wind than in the slow solar wind, and the fast solar wind is hotter than the slow solar wind.
KW - magnetic reconnection
KW - plasmas
KW - solar wind
KW - turbulence
KW - INTERPLANETARY MAGNETIC-FIELD
KW - NONLINEAR ALFVEN WAVES
KW - MAGNETOHYDRODYNAMIC TURBULENCE
KW - ULYSSES OBSERVATIONS
KW - PLASMA PARAMETERS
KW - RADIAL EVOLUTION
KW - DISCONTINUITIES
KW - RECONNECTION
KW - SPEED
KW - DISTRIBUTIONS
U2 - 10.1088/2041-8205/739/2/L61
DO - 10.1088/2041-8205/739/2/L61
M3 - Journal article
VL - 739
SP - -
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
SN - 2041-8205
IS - 2
M1 - L61
ER -