Limits on the core temperature anisotropy of solar wind protons - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Annales Geophysicae Année : 2006

Limits on the core temperature anisotropy of solar wind protons

Résumé

We analyse the temperature anisotropy of the protons in the solar wind and thereby concentrate on plasma data obtained in the year 1976 of the Helios 1 and Helios 2 missions. We derive the core proton temperatures and , in the directions perpendicular and parallel to the magnetic field, as well as the core parallel plasma beta, . The data are separately analysed for two distance ranges, AU and AU, and divided into 24 bins for the plasma beta, in the range from to , and into 72 bins for the total temperature anisotropy, , which is here considered in the range from ?0.9 to 0.9. The number of spectra in each bin is determined to obtain distributions. The statistical results are presented in two-dimensional histograms. For each column we define a critical upper and lower limit of the anisotropy. The resulting empirical points are compared with the known theoretical instability thresholds. The protons are found to come with increasing radial distance closer to the fire-hose instability threshold.
Fichier principal
Vignette du fichier
angeo-24-2057-2006.pdf (538.11 Ko) Télécharger le fichier
Origine : Accord explicite pour ce dépôt
Loading...

Dates et versions

hal-00318139 , version 1 (18-06-2008)

Identifiants

  • HAL Id : hal-00318139 , version 1

Citer

E. Marsch, L. Zhao, C.-Y. Tu. Limits on the core temperature anisotropy of solar wind protons. Annales Geophysicae, 2006, 24 (7), pp.2057-2063. ⟨hal-00318139⟩

Collections

INSU EGU
60 Consultations
105 Téléchargements

Partager

Gmail Facebook X LinkedIn More