On the Heating of the Slow Solar Wind by Imbalanced Alfvén-wave Turbulence from 0.06 to 1 au: Parker Solar Probe and Solar Orbiter Observations by Sofiane Bourouaine, Jean C. Perez, Benjamin D. G. Chandran, Vamsee K. Jagarlamudi, Nour E. Raouafi, Jasper S. Halekas

“…In this work we analyze plasma and magnetic field data provided by the Parker Solar Probe and Solar Orbiter missions to investigate the radial evolution of the heating of Alfvénic slow wind by imbalanced Alfvén-wave (AW) turbulent fluctuations from 0.06 to 1 au. in our analysis we focus on slow solar-wind intervals with highly imbalanced and incompressible turbulence (i.e., magnetic compressibility C _B = δ B / B ≤ 0.25, plasma compressibility C _n = δ n / n ≤ 0.25, and normalized cross helicity σ _c ≥ 0.65). …”
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Quasi-parallel Antisunward-propagating Whistler Waves Associated with the Electron Deficit in the Near-Sun Solar Wind: Particle-in-cell Simulation by Alfredo Micera, Daniel Verscharen, Jesse T. Coburn, Maria Elena Innocenti

“…In situ observations of the solar wind have shown that the electron velocity distribution function (VDF) consists of a quasi-Maxwellian core, comprising most of the electron population, and two sparser components: the halo, which are suprathermal and quasi-isotropic electrons, and an escaping beam population, the strahl. Recent Parker Solar Probe (PSP) and Solar Orbiter (SO) observations have added one more ingredient to the known nonthermal features, the deficit—a depletion in the sunward region of the VDF, already predicted by exospheric models but never so extensively observed. …”
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Delay of Near-relativistic Electrons with Respect to Type III Radio Bursts throughout the Inner Heliosphere by J. G. Mitchell, E. R. Christian, G. A. de Nolfo, C. M. S. Cohen, M. E. Hill, A. Kouloumvakos, A. W. Labrador, R. A. Leske, D. J. McComas, R. L. McNutt Jr., D. G. Mitchell, M. Shen, N. A. Schwadron, M. E. Wiedenbeck, S. D. Bale, M. Pulupa

“…In this study, we examine energetic electron onsets and type III radio bursts observed by the Integrated Science Investigation of the Sun (IS⊙IS) and the FIELDS Radio Frequency Spectrometer instrument on Parker Solar Probe at a variety of heliocentric distances. …”
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Differentiating the Acceleration Mechanisms in the Slow and Alfvénic Slow Solar Wind by Yeimy J. Rivera, Samuel T. Badman, J. L. Verniero, Tania Varesano, Michael L. Stevens, Julia E. Stawarz, Katharine K. Reeves, Jim M. Raines, John C. Raymond, Christopher J. Owen, Stefano A. Livi, Susan T. Lepri, Enrico Landi, Jasper. S. Halekas, Tamar Ervin, Ryan M. Dewey, Rossana De Marco, Raffaella D’Amicis, Jean-Baptiste Dakeyo, Stuart D. Bale, B. L. Alterman

“…Through a well-timed conjunction between Solar Orbiter and Parker Solar Probe (PSP), we trace the energetics of slow wind to compare with a neighboring Alfvénic slow solar wind stream. …”
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