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A novel method to measure the solar wind speed

Moncuquet, Michel; Issautier, Karine; Meyer-Vernet, Nicole +1 more

We propose a novel method to measure in situ the bulk speed of a space plasma. It is based on the analysis of the electrostatic field spectrum produced by the Doppler-shifted thermal fluctuations of the plasma ions which can be measured with a sensitive receiver at the terminals of a passive electric antenna. We present a preliminary application i…

Reply [to “Comment on ‘The underlying magnetic field direction in Ulysses observations of the southern polar heliosphere’ by Forsyth et al.”]

Balogh, A.; McComas, D. J.; Forsyth, R. J. +2 more

Interplanetary observations of solar g-mode oscillations?

Riley, Pete; Sonett, C. P.

By applying spectral techniques to magnetic field and plasma data from Helios 1 and 2, Pioneer 1 and 2, and Voyager 1 and 2 missions, an attempt has been made to find evidence for solar g-mode oscillations in the solar wind. It is demonstrated that analysis employing simple spectral techniques is unlikely to detect such oscillations. Using the mul…

Corotating shock accelerated particles guided by wavy spiral magnetic fields in the solar wind at high heliographic latitudes

Lou, Yu-Qing

We propose the persistent presence of randomly fluctuating, large-amplitude, long-timescale wavy spiral magnetic fields in the solar wind at all heliographic latitudes. These Alfvénic fluctuations can be generated by gradual evolution of solar coronal holes or by interplanetary Kelvin-Helmholtz instabilities occurring around the two conical interf…

Latitudinal variation of the heliospheric magnetic field during solar minimum

Bravo, S.; Stewart, G. A.

Ulysses' observations of the heliospheric magnetic field have shown that, above a narrow low-latitude region, the intensity of the radial component of the field is independent of latitude. Here we present a theoretical explanation of this behaviour based on an MHD model of the solar wind applicable at solar minimum, which corresponds to the Ulysse…

Kinetic temperature ratios of O⁶⁺ and He²⁺: Observations from Wind/MASS and Ulysses/SWICS

Cohen, C. M. S.; Gloeckler, G.; Wilken, B. +4 more

We present results from a two spacecraft study of the ratio of O⁶⁺ and He²⁺ kinetic temperatures as a function of solar wind speed. Data from the Wind/MASS and Ulysses/SWICS instruments both indicate the O⁶⁺/He²⁺ kinetic temperature ratio increases with increasing solar wind speed, peaking near 500 km/s.…

Comment on “The underlying magnetic field direction in Ulysses observations of the southern polar heliosphere” by Forsyth et al.

Smith, Charles W.; Bieber, John W.