Contextual Predictions for Parker Solar Probe II: Turbulence Properties and Taylor Hypothesis. (arXiv:1902.03340v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Chhiber_R/0/1/0/all/0/1">Rohit Chhiber</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Usmanov_A/0/1/0/all/0/1">Arcadi V. Usmanov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Matthaeus_W/0/1/0/all/0/1">William H. Matthaeus</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Parashar_T/0/1/0/all/0/1">Tulasi N. Parashar</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Goldstein_M/0/1/0/all/0/1">Melvyn L. Goldstein</a>
The Parker Solar Probe (PSP) primary mission extends seven years and consists
of 24 orbits of the Sun with descending perihelia culminating in a closest
approach of ($sim 9.8~R_odot$). In the course of these orbits PSP will pass
through widely varying conditions, including anticipated large variations of
turbulence properties such as energy density, correlation scales and cross
helicities. Here we employ global magnetohydrodynamics simulations with
self-consistent turbulence transport and heating citep{usmanov2018} to preview
likely conditions that will be encountered by PSP, by assuming suitable
boundary conditions at the coronal base. The code evolves large-scale
parameters — such as velocity, magnetic field, and temperature — as well as
turbulent energy density, cross helicity, and correlation scale. These computed
quantities provide the basis for evaluating additional useful parameters that
are derivable from the primary model outputs. Here we illustrate one such
possibility in which computed turbulence and large-scale parameters are used to
evaluate the accuracy of the Taylor “frozen-in” hypothesis along the PSP
trajectory. Apart from the immediate purpose of anticipating turbulence
conditions that PSP will encounter, as experience is gained in comparisons of
observations with simulated data, this approach will be increasingly useful for
planning and interpretation of subsequent observations.
The Parker Solar Probe (PSP) primary mission extends seven years and consists
of 24 orbits of the Sun with descending perihelia culminating in a closest
approach of ($sim 9.8~R_odot$). In the course of these orbits PSP will pass
through widely varying conditions, including anticipated large variations of
turbulence properties such as energy density, correlation scales and cross
helicities. Here we employ global magnetohydrodynamics simulations with
self-consistent turbulence transport and heating citep{usmanov2018} to preview
likely conditions that will be encountered by PSP, by assuming suitable
boundary conditions at the coronal base. The code evolves large-scale
parameters — such as velocity, magnetic field, and temperature — as well as
turbulent energy density, cross helicity, and correlation scale. These computed
quantities provide the basis for evaluating additional useful parameters that
are derivable from the primary model outputs. Here we illustrate one such
possibility in which computed turbulence and large-scale parameters are used to
evaluate the accuracy of the Taylor “frozen-in” hypothesis along the PSP
trajectory. Apart from the immediate purpose of anticipating turbulence
conditions that PSP will encounter, as experience is gained in comparisons of
observations with simulated data, this approach will be increasingly useful for
planning and interpretation of subsequent observations.
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