Parker Solar Probe Observations of Magnetic Reconnection Exhausts in Quiescent Plasmas near the Sun Journal Article uri icon

Overview

abstract

  • Abstract; Parker Solar Probe observations are analyzed for the presence of reconnection exhausts across current sheets (CSs) within R < 0.26 au during encounters 4–11. Exhausts are observed with nearly equal probability at all radial distances with a preference for quiescent Tp < 0.80 MK plasmas typical of a slow-wind regime. High Tp > 0.80 MK plasmas of a fast wind characterized by significant transverse fluctuations rarely support exhausts irrespective of the CS width. Exhaust observations demonstrate the presence of local temperature gradients across several CSs with a higher-Tp plasma on locally closed fields and a lower-Tp plasma on locally open field lines for an interchange-type reconnection. A CS geometry analysis directly supports the property that X-lines bisect the magnetic field rotation θ-angle, whether the fields and plasmas are asymmetric or not, to maximize reconnection rates and available magnetic energy. The CS normal width d; cs distributions suggest that a multiscale reconnection process through nested layers of bifurcated CSs may be responsible for observed power-law distributions beyond the median d; cs ∼ 1000 km with an exponential d; cs distribution present for ion kinetic dissipation scales below this median. Magnetic field shear θ-angles are essentially identical at R < 0.26 and 1 au with medians at θ ∼ 55° near the Sun and θ ∼ 65° at 1 au. In contrast, the tangential flow shear distributions are different near and far from the Sun. A bimodal flow shear angle distribution is present near the Sun with strong shear flow magnitudes. This distribution is modified with radial distance toward a relatively flat distribution of weaker flow shear magnitudes.

publication date

  • April 1, 2024

has restriction

  • gold

Date in CU Experts

  • April 16, 2024 11:52 AM

Full Author List

  • Eriksson S; Swisdak M; Mallet A; Kruparova O; Livi R; Romeo O; Bale SD; Kasper JC; Larson DE; Pulupa M

author count

  • 10

Other Profiles

International Standard Serial Number (ISSN)

  • 0004-637X

Electronic International Standard Serial Number (EISSN)

  • 1538-4357

Additional Document Info

start page

  • 76

end page

  • 76

volume

  • 965

issue

  • 1