Observations of Heating along Intermittent Structures in the Inner Heliosphere from PSP Data

R.A. Qudsi (1) , B. A. Maruca (2) , W.H. Matthaeus (2) , T. N. Parashar (1) , Riddhi Bandyopadhyay (1) , R. Chhiber (1, 2) , A. Chasapis (3) , Melvyn L. Goldstein (4) , S.D. Bale (5, 6) , J.W. Bonnell (5) , Thierry Dudok de Wit (7) , K. Goetz (8) , P.R. Harvey (5) , R.J Macdowall (4) , D. Malaspina (3) , Marc Pulupa (5) , J.C. Kasper (9) , K.E. Korreck (9) , A.W. Case (9) , M. Stevens (9) , P. Whittlesey (5) , D. Larson (5) , R. Livi (10) , M. Velli (11) , N. Raouafi (12)

1 University of Delaware [Newark]
2 Bartol Research Institute
3 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
4 GSFC - NASA Goddard Space Flight Center
5 UC Berkeley - University of California [Berkeley]
6 Imperial College London
7 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
8 UMN - University of Minnesota [Twin Cities]
9 Smithsonian Astrophysical Observatory
10 SSL - Space Sciences Laboratory [Berkeley]
11 EPSS - Department of Earth, Planetary and Space Sciences [Los Angeles]
12 APL - Johns Hopkins University Applied Physics Laboratory [Laurel, MD]

The solar wind proton temperature at 1 au has been found to be correlated with small-scale intermittent magnetic structures, i.e., regions with enhanced temperature are associated with coherent structures, such as current sheets. Using Parker Solar Probe data from the first encounter, we study this association using measurements of the radial proton temperature, employing the partial variance of increments (PVI) technique to identify intermittent magnetic structures. We observe that the probability density functions of high PVI events have higher median temperatures than those with lower PVI. The regions in space where PVI peaks were also locations that had enhanced temperatures when compared with similar regions, suggesting a heating mechanism in the young solar wind that is associated with intermittency developed by a nonlinear turbulent cascade in the immediate vicinity.

Domains: Sciences of the Universe [physics]; Astrophysics [astro-ph]; Solar and Stellar Astrophysics [astro-ph.SR]

R.A. Qudsi, B. A. Maruca, W.H. Matthaeus, T. N. Parashar, Riddhi Bandyopadhyay, et al.. Observations of Heating along Intermittent Structures in the Inner Heliosphere from PSP Data. The Astrophysical Journal Supplement, 2020, 246 (2), pp.46. ⟨10.3847/1538-4365/ab5c19⟩. ⟨insu-02942198⟩