Sensitivity of solar wind mass flux to coronal temperature

D. Stansby , L. Berčič (1) , L. Matteini , C. J. Owen , R. J. French , D. Baker , S. T. Badman

1 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics

Solar wind models predict that the mass flux carried away from the Sun in the solar wind should be extremely sensitive to the temperature in the corona, where the solar wind is accelerated. We perform a direct test of this prediction in coronal holes and active regions using a combination of in situ and remote sensing observations. For coronal holes, a 50% increase in temperature from 0.8 to 1.2 MK is associated with a tripling of the coronal mass flux. This trend is maintained within active regions at temperatures over 2 MK, with a four-fold increase in temperature corresponding to a 200-fold increase in coronal mass flux.

Code to reproduce the figures presented in this Letter is available at https://github.com/dstansby/publication-code. PSP and WIND data are available from https://spdf.gsfc.nasa.gov/pub/data, GONG data from https://gong2.nso.edu/oQR/zqs/, SDO and SOHO data from http://jsoc.stanford.edu/, and EIS data from http://solarb.mssl.ucl.ac.uk/SolarB/.

Mots clés: Sun: corona; Sun: heliosphere; solar wind; stars: winds; outflows

Domaines: Planète et Univers [physics]; Astrophysique [astro-ph]

D. Stansby, L. Berčič, L. Matteini, C. J. Owen, R. J. French, et al.. Sensitivity of solar wind mass flux to coronal temperature. Astronomy and Astrophysics - A&A, 2021, 650, ⟨10.1051/0004-6361/202039789⟩. ⟨insu-03713772⟩