In this study, we explore the statistics of pressure fluctuations in kinetic collisionless turbulence. A 2.5D kinetic particleincell simulation of decaying turbulence is used to investigate pressure balance via the evolution of thermal and magnetic pressure in a plasma with β of order unity. We also discuss the behaviour of thermal, magnetic, and total pressure structure functions and their corresponding wavenumber spectra. The total pressure spectrum exhibits a slope of −7/3 extending for about a decade in the ioninertial range. In contrast, shallower −5/3 spectra are characteristic of the magnetic pressure and thermal pressure. The steeper total pressure spectrum is a consequence of cancellation caused by densitymagnetic field magnitude anticorrelation. Further, we evaluate higher order total pressure structure functions in an effort to discuss intermittency and compare the power exponents with higher order structure functions of velocity and magnetic fluctuations. Finally, applications to astrophysical systems are also discussed.
 Award ID(s):
 2103874
 NSFPAR ID:
 10331091
 Date Published:
 Journal Name:
 Physical review fluids
 ISSN:
 24699918
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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