@article{27c8e089a5f541e59b7bb0248c4ccb41,
title = "Interchange reconnection as the source of the fast solar wind within coronal holes",
abstract = "The fast solar wind that fills the heliosphere originates from deep within regions of open magnetic field on the Sun called {\textquoteleft}coronal holes{\textquoteright}. The energy source responsible for accelerating the plasma is widely debated; however, there is evidence that it is ultimately magnetic in nature, with candidate mechanisms including wave heating 1,2 and interchange reconnection3–5. The coronal magnetic field near the solar surface is structured on scales associated with {\textquoteleft}supergranulation{\textquoteright} convection cells, whereby descending flows create intense fields. The energy density in these {\textquoteleft}network{\textquoteright} magnetic field bundles is a candidate energy source for the wind. Here we report measurements of fast solar wind streams from the Parker Solar Probe (PSP) spacecraft6 that provide strong evidence for the interchange reconnection mechanism. We show that the supergranulation structure at the coronal base remains imprinted in the near-Sun solar wind, resulting in asymmetric patches of magnetic {\textquoteleft}switchbacks{\textquoteright}7,8 and bursty wind streams with power-law-like energetic ion spectra to beyond 100 keV. Computer simulations of interchange reconnection support key features of the observations, including the ion spectra. Important characteristics of interchange reconnection in the low corona are inferred from the data, including that the reconnection is collisionless and that the energy release rate is sufficient to power the fast wind. In this scenario, magnetic reconnection is continuous and the wind is driven by both the resulting plasma pressure and the radial Alfv{\'e}nic flow bursts.",
author = "Bale, {S. D.} and Drake, {J. F.} and McManus, {M. D.} and Desai, {M. I.} and Badman, {S. T.} and Larson, {D. E.} and M. Swisdak and Horbury, {T. S.} and Raouafi, {N. E.} and T. Phan and M. Velli and McComas, {D. J.} and Cohen, {C. M.S.} and D. Mitchell and O. Panasenco and Kasper, {J. C.}",
note = "Funding Information: The FIELDS, SWEAP and ISOIS suites were designed, developed and are operated under NASA contract NNN06AA01C. We acknowledge the extraordinary contributions of the PSP mission operations and spacecraft engineering team at the Johns Hopkins University Applied Physics Laboratory. M.V. was supported in part by the International Space Science Institute, Bern, through the J. Geiss fellowship. J.F.D. and M.S. were supported by the NASA Drive Science Center on Solar Flare Energy Release (SolFER) under Grant 80NSSC20K0627, NASA Grant 80NSSC22K0433 and NSF Grant PHY2109083. T.S.H. is supported by STFC grant ST/W001071/1. O.P. was supported by the NASA Grant 80NSSC20K1829. Elements of this work benefited from discussions at the meeting of Team 463 at the International Space Science Institute (ISSI). Funding Information: The PSP mission data used in this study are openly available at the NASA Space Physics Data Facility ( https://nssdc.gsfc.nasa.gov ) and were analysed using the IDL/SPEDAS software package ( https://spedas.org/blog/ ). The computer simulations used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under contract no. DE-AC02- 05CH11231. Simulation data is available at https://doi.org/10.5281/zenodo.7562035 . Funding Information: The FIELDS, SWEAP and ISOIS suites were designed, developed and are operated under NASA contract NNN06AA01C. We acknowledge the extraordinary contributions of the PSP mission operations and spacecraft engineering team at the Johns Hopkins University Applied Physics Laboratory. M.V. was supported in part by the International Space Science Institute, Bern, through the J. Geiss fellowship. J.F.D. and M.S. were supported by the NASA Drive Science Center on Solar Flare Energy Release (SolFER) under Grant 80NSSC20K0627, NASA Grant 80NSSC22K0433 and NSF Grant PHY2109083. T.S.H. is supported by STFC grant ST/W001071/1. O.P. was supported by the NASA Grant 80NSSC20K1829. Elements of this work benefited from discussions at the meeting of Team 463 at the International Space Science Institute (ISSI). Publisher Copyright: {\textcopyright} 2023, The Author(s).",
year = "2023",
month = jun,
day = "8",
doi = "10.1038/s41586-023-05955-3",
language = "English (US)",
volume = "618",
pages = "252--256",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "7964",
}