Magnetic modulation of solar luminosity by photospheric activity

  title={Magnetic modulation of solar luminosity by photospheric activity},
  author={Peter V. Foukal and Judith Lean},
  journal={The Astrophysical Journal},
The behavior of slow changes in solar irradiance S is studied using measurements obtained with radiometers on the SMM and Nimbus 7 spacecraft. The general downtrend in the radiometer readings is examined by removing the influence of sunspot blocking and comparing the residual irradiance variations with changes in facular and network radiation as indicated by the He I 10830 and CaK indices. The time-integrated sunspot and facular contributions to irradiance variation and its implications for… Expand
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  • P. Foukal
  • Physics
  • Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
  • 1990
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