Energetic particle transport in the interplanetary medium is known to beaffected by magnetic structures. It has been demonstrated for solar energeticparticles in near-Earth orbit studies, and also for the more energetic cosmicrays. In this paper, we show observational evidence that intensity variationsof solar energetic particles can be correlated with the occurrence of helicalmagnetic flux tubes and their boundaries. The analysis is carried out usingdata from Parker Solar Probe orbit 5, in the period 2020 May 24 to June 2. Weuse FIELDS magnetic field data and energetic particle measurements from theIntegrated Science Investigation of the Sun (\isois) suite on the Parker SolarProbe. We identify magnetic flux ropes by employing a real-space evaluation ofmagnetic helicity, and their potential boundaries using the Partial Variance ofIncrements method. We find that energetic particles are either confined withinor localized outside of helical flux tubes, suggesting that the latter act astransport boundaries for particles, consistent with previously developedviewpoints.
Parker Solar Probe Observations of Helical Structures as Boundaries for Energetic Particles
F. Pecora;S. Servidio;A. Greco;
2021-01-01
Abstract
Energetic particle transport in the interplanetary medium is known to beaffected by magnetic structures. It has been demonstrated for solar energeticparticles in near-Earth orbit studies, and also for the more energetic cosmicrays. In this paper, we show observational evidence that intensity variationsof solar energetic particles can be correlated with the occurrence of helicalmagnetic flux tubes and their boundaries. The analysis is carried out usingdata from Parker Solar Probe orbit 5, in the period 2020 May 24 to June 2. Weuse FIELDS magnetic field data and energetic particle measurements from theIntegrated Science Investigation of the Sun (\isois) suite on the Parker SolarProbe. We identify magnetic flux ropes by employing a real-space evaluation ofmagnetic helicity, and their potential boundaries using the Partial Variance ofIncrements method. We find that energetic particles are either confined withinor localized outside of helical flux tubes, suggesting that the latter act astransport boundaries for particles, consistent with previously developedviewpoints.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
