SH025-08
Whistler Waves in the Young Solar Wind: Properties, Origin, and Consequences for Particles
Thursday, 10 December 2020: 10:51
Virtual
Oleksiy V Agapitov1, Thierry Dudok de Wit2, James Frederick Drake3, Marc Swisdak4, David Malaspina5, Forrest Mozer6, Clara Froment7, Vladimir Krasnoselskikh2, Stuart D Bale8, John W Bonnell9, Christopher Carew Chaston10, Anthony W Case11, Keith Goetz12, Justin Christophe Kasper13, Kelly E Korreck11, Davin Larson14, Ken Livi15, Robert J MacDowall16, Marc Pulupa14, Michael Louis Stevens11, Phyllis L Whittlesey14 and John R Wygant17, (1)University of California Berkeley, Berkeley, CA, United States, (2)LPC2E, CNRS and University of Orléans, Orléans, France, (3)University of Maryland College Park, College Park, MD, United States, (4)University of Maryland, College Park, MD, United States, (5)University of Colorado, Astrophysical and Planetary Sciences Department, Boulder, CO, United States, (6)University of California, Berkeley, Berkeley, CA, United States, (7)University of Oslo, Institute of Theoretical Astrophysics, Oslo, Norway, (8)University of California Berkeley, Space Sciences Laboratory, Berkeley, CA, United States, (9)University of California, Berkeley, Space Sciences Laboratory, Berkeley, CA, United States, (10)Univ California Berkeley, Berkeley, CA, United States, (11)Smithsonian Astrophysical Observatory, Cambridge, MA, United States, (12)University of Minnesota, School of Physics and Astronomy, Minneapolis, MN, United States, (13)University of Michigan, Climate and Space Sciences and Engineering, Ann Arbor, MI, United States, (14)Space Sciences Laboratory, University of California Berkeley, Berkeley, CA, United States, (15)The Johns Hopkins University, Baltimore, United States, (16)NASA/Goddard Space Flight Center, Greenbelt, United States, (17)University of Minnesota, Minneapolis, MN, United States
Abstract:
Observations by the Parker Solar Probe mission of the solar wind at about 35 solar radii reveal the existence of whistler wave packets with frequencies below 0.1fce (20-150 Hz in the spacecraft frame). These waves bursts often coincide with local minima of the magnetic field magnitude observed in the vicinity of the switchbacks boundaries. The Poynting flux indicates sunward propagation that leads to a significant Doppler frequency downshift from 200-300 Hz to 20-80 Hz (from 0.2fce to 0.5fce). The polarization of these waves varies from quasi-parallel to significantly oblique. Their peak amplitude can be as large as 1-4 nT (up to 20% of the background magnetic field magnitude). The generation of these waves is supported by the modified electron distribution with increased transverse temperature anisotropy inside the magnetic hole. Sunward propagating whistler waves scatter the high energy solar wind electrons in the energy range up to 1 keV and potentially play a significant role in breaking the heat flux and scattering the Strahl population of suprathermal electrons into a halo population.
