Abstract
Coronal holes on the Sun have been observed at individual frequencies for quite a long time in the wavelength range from radio to X-rays. Observations in a wide range of radio frequencies are carried out with the RATAN-600 radio telescope. An analysis of long-term spectral observations of the RATAN-600 radio telescope showed that the emission spectrum of coronal holes is radically different from the spectrum of active formations above sunspots, but, differing markedly from the spectrum of the quiet Sun, it also has similarities with it. It has been established that the radio emission of coronal holes has an adiabatic spectrum and does not contain noticeable coherent radiation, that is, recombination radio lines and lines of the fine structure of hydrogen and other elements.
REFERENCES
M. Waldmeier, Z. Astrophys. 38, 219 (1956).
S. R. Cranmer, Living Rev. Solar Phys. 6, 3 (2009).
V. M. Bogod, A. M. Alesin, and A. A. Pervakov, Astrophys. Bull. 66, 205 (2011).
J. P. Wild, Astrophys. J. 115, 206 (1952).
A. F. Dravskikh and Z. V. Dravskikh, Sov. Astron. 32, 104 (1988).
A. F. Dravskikh, N. G. Peterova, and N. A. Topchilo, Astron. Rep. 63, 229 (2019).
A. F. Dravskikh and Yu. A. Dravskikh, Astron. Rep. 65, 705 (2021).
A. F. Dravskikh and Yu. A. Dravskikh, Astron. Rep. 66, 490 (2022).
V. V. Zheleznyakov, Radio Emission of the Sun and Planets, Vol. 25 of International Series of Monographs in Natural Philosophy (Moscow, 1964; Elsevier, Amsterdam, 1970).
L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics, Vol. 5: Statistical Physics (Nauka, Moscow, 1995; Pergamon, Oxford, 1980).
S. F. Smerd, Austral. J. Sei. Res. A 3, 34 (1950).
J. V. Zirker, Rev. Geophys. Space Phys. 15, 257 (1977).
V. N. Borovik, V. G. Medar’, and V. I. Garaimov, in Proceedings of the International Conference on Sun in the Activity Maximum and Solar–Stellar Counterparts, Pulkovo, Sept. 17–22, 2000 (GAO RAN, St. Petersburg, 2000), p. 112.
M. D. Papagiannis and K. B. Baker, Solar Phys. 79, 365 (1982).
V. N. Borovik, M. S. Kurbanov, M. A. Livshits, and B. I. Ryabov, Sov. Astron. 34, 522 (1990).
O. A. Golubchina, Astron. Rep. 65, 322 (2021).
ACKNOWLEDGMENTS
We thank A.D. Shramko and S.A. Guseva for their help.
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Dravskikh, A.F., Dravskikh, Y.A. Adiabatic Radio Emission Spectrum of the Sun’s Coronal Holes. Astron. Rep. 67, 513–519 (2023). https://doi.org/10.1134/S1063772923050037
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DOI: https://doi.org/10.1134/S1063772923050037