Dependence of Solar Wind Proton Temperature on the Polarization Properties of Alfvénic Fluctuations at Ion-kinetic Scales

  title={Dependence of Solar Wind Proton Temperature on the Polarization Properties of Alfv{\'e}nic Fluctuations at Ion-kinetic Scales},
  author={Lloyd D. Woodham and Robert T. Wicks and Daniel Verscharen and Jason M. TenBarge and Gregory Gershom Howes},
  journal={The Astrophysical Journal},
We use fluctuating magnetic helicity to investigate the polarization properties of Alfvénic fluctuations at ion-kinetic scales in the solar wind as a function of β p , the ratio of proton thermal pressure to magnetic pressure, and θ vB , the angle between the proton flow and local mean magnetic field, B 0. Using almost 15 yr of Wind observations, we separate the contributions to helicity from fluctuations with wavevectors, k , quasi-parallel and oblique to B 0, finding that the helicity of Alfv… 
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