Dynamics of Coronal Hole Boundaries

Abstract

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Formation and Reconnection of Three-dimensional Current Sheets with a Guide Field in the Solar Corona

“…Power-law fit exponents for each of the spatial scale ranges in the density Fourier power spectra of the structured, intermittent reconnection outflow along the pseudostreamer external spine fan corresponding to the Separatrix-Web arc (Antiochos et al 2011;Higginson et al 2017b). Our results confirm the smooth interchange reconnection pseudostreamer outflow scenario of Masson et al (2014) and show with a sufficiently resolved current sheet, the plasmoid instability during reconnection provides a potential explanation for some of the variability observed in pseudostreamer wind (Crooker et al 2012Owens et al 2014).…”

“…Higginson et al (2017c) have demonstrated that the 3D structure of reconnection-generated magnetic islands in the heliospheric current sheet are consistent with the observations of small-scale flux rope transients in the slow solar wind (Feng et al 2008;Cartwright & Moldwin 2008Kilpua et al 2009;Yu et al 2014). And Janvier et al (2014) have argued that the power-law distribution of the sizes of these small flux rope transients appears compatible with the power-law distributions of magnetic island plasmoids obtained in various reconnection studies (e.g.…”

“…These Alfvénic fluctuations propagate both down the flux tube toward the lower boundary and along the direction of the flux tube that opens up into the solar wind. Thus, depending on the guide field strength during the interchange reconnection process, in addition to highly-structured density fluctuation outflow, one may also see periods of highly-structured magnetic field fluctuations or Alfvénic field rotations in pseudostreamer wind (e.g., see Higginson et al 2017c). …”

Magnetic Connectivity in the Corona as a Source of Structure in the Solar Wind

“…Many numerical investigations of the slow SW structure and origin have been conducted (Edmondson et al, ; Higginson et al, ; ; Higginson & Lynch, ; Linker et al, ), although these do not resolve the SW scale sizes in question. The results presented here show field line‐integrated plasma and magnetic field properties for a rectangular volume of the coronal and photospheric magnetic field.…”

Diagnosing solar wind origins usingin situmeasurements in the inner heliosphere

“…In contrast to the fast wind, the plasma properties of the slow solar wind (v <∼ 500 km/s) are much more variable (Schwenn 2007), and although it must have a number of different solar sources (Abbo et al 2016), it is not clear how these sources contribute to the different parts of the slow solar wind measured in-situ. In general there are two possible generation mechanisms for the slow wind: it can flow continuously on magnetic field lines that maintain a connection from the base of the corona to the heliosphere, in a similar manner to the fast solar wind (Wang & Sheeley 1990;Cranmer et al 2007;Wang 2010), or can be released transiently from closed magnetic field lines undergoing interchange re-connection with the open magnetic field lines that connect to the heliosphere (Sheeley et al 1997;Einaudi et al 2001;Rouillard et al 2010;Higginson et al 2017).…”