SPECTRAL SLOPE VARIATION AT PROTON SCALES FROM FAST TO SLOW SOLAR WIND
- INAF-IAPS, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy, Via del Fosso del Cavaliere 100, I-00133 Roma (Italy)
We investigated the behavior of the spectral slope of interplanetary magnetic field fluctuations at proton scales for selected high-resolution time intervals from the WIND and MESSENGER spacecraft at 1 AU and 0.56 AU, respectively. The analysis was performed within the profile of high-speed streams, moving from fast to slow wind regions. The spectral slope showed a large variability between –3.75 and –1.75 and a robust tendency for this parameter to be steeper within the trailing edge, where the speed is higher, and to be flatter within the subsequent slower wind, following a gradual transition between these two states. The value of the spectral index seems to depend firmly on the power associated with the fluctuations within the inertial range; the higher the power, the steeper the slope. Our results support previous analyses suggesting that there must be some response of the dissipation mechanism to the level of the energy transfer rate along the inertial range.
- OSTI ID:
- 22364980
- Journal Information:
- Astrophysical Journal Letters, Vol. 793, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
RADIAL DEPENDENCE OF THE FREQUENCY BREAK BETWEEN FLUID AND KINETIC SCALES IN THE SOLAR WIND FLUCTUATIONS
Statistical properties of low-frequency magnetic field fluctuations in the solar wind from 0. 29 to 1. 0 AU during solar minimum conditions: HELIOS 1 and HELIOS 2