Abstract
The Extreme Limb Photometer (ELP) has been used to measure the irradiance fluctuation of the Sun due to selected active regions. Forty-five active regions that were completely scanned at various disk positions are included in the analysis. The contribution of these active regions to a global solar irradiance fluctuation has been correlated with photometric sunspot and facular indices (PSI and PFI) using published values of sunspot and calcium plage areas. The measured ELP fluctuations are converted to a global brightness fluctuation, ΔB/B. The sunspot component of ΔB/B correlates with PSI with r = 0.95. The facular component of ΔB/B correlates with PFI with r - 0.72. The expression for PFI is important to the question of energy balance between sunspots and faculae and the results presented here are not incompatible with energy balance between the two phenomena; that is the energy deficit of sunspots may be balanced by the energy excess of faculae.
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References
Allen, C. W.: 1973, Astrophysical Quantities, 2nd ed., Athlone Press, London.
Bruning, D. H. and LaBonte, B. J.: 1983, Astrophys. J. 271, 853.
Chandler, J. P.: 1972, Technometrics 14, 71.
Chapman, G. A.: 1980, Astrophys. J. 242, L45.
Chapman, G. A.: 1984, Nature 308, 252.
Chapman, G. A. and Meyer, A. D.: 1981, in L. E. Cram and J. H. Thomas (eds.), The Physics of Sunspots, Sunspot, NM, Sacramento Peak Observatory.
Chapman, G. A. and Klabunde, D. P.: 1982, Astrophys. J. 261, 387.
Donnelly, R. F., Heath, D. F., Lean, J. L., and Rottman, G. J.: 1984, in B. J. LaBonte, G. A. Chapman, H. S. Hudson, and R. C. Willson (eds.), Solar Irradiance Variations on Active Region Time Scales, NASA CP-2310, p. 233.
Eddy, J. A., Gilliland, R. L. and Hoyt, D. V.: 1982, Nature, 300, 689.
Foukal, P. V. and Vernazza, J.: 1979, Astrophys. J. 234, 707.
Foukal, P. V., Fowler, L. A., and Lifshitz, M.: 1983, Astrophys. J. 267, 863.
Hirayama, T., and Okamoto, T.: 1981, Solar Phys. 73, 37.
Hoyt, D. V., and Eddy, J. A.: 1983, Geophys. Res. Letters 10, 509.
Hudson, H. S., Silva, S., Woodard, M., and Willson, R. C.: 1982, Solar Phys. 76, 211.
Lawrence, J. K., Chapman, G. A., Herzog, A. D., and Shelton, J. C.: 1983, Bull. Am. Astron. Soc. 15, 951.
Lawrence, J. K., Chapman, G. A., Herzog, A. D., and Shelton, J. C.: 1985, Astrophys. J. 292, 297.
Meyer, A. D.: 1983, M.S. Thesis, CSU, Northridge.
Oster, L., Schatten, K., and Sofia, S.: 1982, Astrophys. J. 256, 768.
Schatten, K. H., Miller, N., Sofia, S., Endal, A. S., Chapman, G., and Hickey, J.: 1985, Astrophys. J. 294, 689.
Sofia, S., Oster, L., and Schatten, K.: 1982, Solar Phys. 80, 87.
Willson, R. C. and Hudson, H. S.: 1981, Astrophys. J. 254, L185.
Willson, R. C., Gulkis, S., Janssen, M., Hudson, H. S., and Chapman, G. A.: 1981, Science 211, 700.
Willson, R. C.: 1982. J. Geophys. Res. 87, 4319.
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Chapman, G.A., Meyer, A.D. Solar irradiance variations from photometry of active regions. Sol Phys 103, 21–31 (1986). https://doi.org/10.1007/BF00154855
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DOI: https://doi.org/10.1007/BF00154855