Güneş Patlaması Kaynaklı Koronal Yağmurların Zürich Güneş Lekesi Sınıfları ile İlişkisi

Abstract

Koronal yağmur, güneş koronasındaki termal kararsızlığın önemli bir göstergesidir. Bu yapılar, Güneşin dış atmosferindeki kütle ve enerji dengesini anlamak için bir anahtar görevindedir. Bu çalışmada, koronal yağmur oluşumunun ve yaşam süresinin, hem güneş patlaması enerjisine (C-, M- ve X-sınıfı) hem de güneş lekelerine ev sahipliği yapan aktif bölgelerin manyetik yapısını nasıl bağlı olduğu incelenmiştir. Sonuçlar, koronal yağmur oluşma olasılığının güneş patlaması enerjisiyle güçlü bir şekilde arttığını göstermektedir. C sınıfı güneş patlamaları daha az sıklıkla yağmur üretirken, M ve X sınıfı güneş patlamaları çok daha yüksek oluşum oranları göstermektedir. Bu eğilim neredeyse tüm güneş leke gruplarında gözlemlenmektedir. Bazı durumlarda, yüksek güneş patlaması enerjisine rağmen yağmur görülmemektedir ki bu da manyetik topolojinin önemli bir rol oynadığını düşündürmektedir. Ayrıca, yağmur süresinin patlama enerjisiyle birlikte arttığı da bulunmuştur. Tipik süreler, C sınıfı patlamalarda on dakikadan X sınıfı olaylarda 150-200 dakikaya kadar yükselmektedir. Bu, daha güçlü patlamaların, uzun süreli soğuma ve yoğunlaşma çevrimlerini sürdürebilen daha uzun ömürlü patlama sonrası koronal luplar ürettiğini göstermektedir. Leke sınıfları arasındaki farklılıklar, koronal lup geometrisinin ve manyetik karmaşıklığın koronal yağmur evrimini etkilediğini de göstermektedir. Genel olarak, sonuçlarımız koronal yağmurun hem patlama enerjisi hem de manyetik yapı tarafından kontrol edildiğini göstermektedir. Bu bulgular, koronal luplarda termal dengesizliği yönlendirmede kütle-enerji girdisi ve manyetik topolojinin birleşik rolünü vurgulamaktadır.

Keywords

• Koronal yağmur
• Güneş Patlaması
• Güneş lekeleri

The Relationship Between Flare-Driven Coronal Rain and Zürich Sunspot Classes

Abstract

Coronal rain is a significant indicator of thermal instability within the solar corona. These structures serve as a key to understanding the balance of mass and energy in the Sun's outer atmosphere. In this study, we investigated how the occurrence and duration of coronal rain depend on both the energy of solar flares (C-,M-, and X-class) and the magnetic structure of the active regions hosting the sunspots. The results indicate that the probability of coronal rain occurrence increases strongly with solar flare energy. While C-class flares produce rain less frequently, M- and X-class flares exhibit much higher formation rates. This trend is observed across almost all sunspot groups. In some instances, despite high flare energy, no rain is observed, suggesting that magnetic topology plays a significant role. Furthermore, it was found that the duration of the rain increases with flare energy. Typical durations range from ten minutes for C-class flares to 150–200 minutes for X-class events. This suggests that more powerful flares generate longer-lived post-flare coronal loops capable of sustaining prolonged cycles of cooling and condensation. Differences observed among sunspot classes also indicate that coronal loop geometry and magnetic complexity influence the occurrence of coronal rain. Overall, our results demonstrate that coronal rain is governed by both flare energy and magnetic structure. These findings underscore the combined role of mass-energy input and magnetic topology in driving thermal instability within coronal loops.

Keywords

• Coronal Rain
• Solar Flare
• Sunspots

References

1. [1] Klimchuk, J.A., 2006. On solving the coronal heating problem. Solar Physics, 234(1), pp.41-77.
2. [2] Sweet, P.A., 1958, January. 14. The neutral point theory of solar flares. In Symposium-International Astronomical Union (Vol. 6, pp. 123-134). Cambridge University Press.
3. [3] Shibata, K. and Magara, T., 2011. Solar flares: magnetohydrodynamic processes. Living Reviews in Solar Physics, 8(1), pp.1-99.
4. [4] Fletcher, L., Dennis, B.R., Hudson, H.S., Krucker, S., Phillips, K., Veronig, A., Battaglia, M., Bone, L., Caspi, A., Chen, Q. and Gallagher, P., 2011. An observational overview of solar flares. Space science reviews, 159(1), p.19.
5. [5] Golub, L. and Pasachoff, J.M., 2010. The solar corona. Cambridge University Press.
6. [6] Fisher, G.H., Canfield, R.C. and McClymont, A.N., 1985. Flare loop radiative hydrodynamics. VI. Chromospheric evaporation due to heating by nonthermal electrons. Astrophysical Journal, Vol. 289, pp. 425-433.
7. [7] Dudík, J., Polito, V., Janvier, M., Mulay, S.M., Karlický, M., Aulanier, G., Zanna, G.D., Dzifčáková, E., Mason, H.E. and Schmieder, B., 2016. Slipping magnetic reconnection, chromospheric evaporation, implosion, and precursors in the 2014 September 10 X1. 6-class solar flare. The Astrophysical Journal, 823(1), p.41.
8. [8] Antolin, P., Vissers, G., Pereira, T.M.D., Voort, L.R.V.D. and Scullion, E., 2015. The multi-thermal and multi-stranded nature of coronal rain. The Astrophysical Journal, 806(1), p.81.

9. [9] Klimchuk, J.A., 2015. Key aspects of coronal heating. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 373(2042).
10. [10] Culhane, J.L., Rapley, C.G., Bentley, R.D., Gabriel, A.H., Phillips, K.J., Acton, L.W., Wolfson, C.J., Catura, R.C., Jordan, C. and Antonucci, E., 1981. X-ray spectra of solar flares obtained with a high-resolution bent crystal spectrometer. Astrophysical Journal, Part 2-Letters to the Editor, vol. 244, Mar. 15, 1981, p. L141-L145. Research supported by the Science Research Council and Lockheed Independent Research Program.
11. [11] Antolin, P., 2020. Thermal instability and non-equilibrium in solar coronal loops: from coronal rain to long-period intensity pulsations. Plasma Physics and Controlled Fusion, 62(1), p.014016.
12. [12] Antolin, P. and Froment, C., 2022. Multi-scale variability of coronal loops set by thermal non-equilibrium and instability as a probe for coronal heating. Frontiers in Astronomy and Space Sciences, 9, p.820116.
13. [13] Foukal, P., 1978. Magnetic loops, downflows, and convection in the solar corona. Astrophysical Journal, Part 1, vol. 223, Aug. 1, 1978, p. 1046-1057., 223, pp.1046-1057.
14. [14] Scullion, E., Voort, L.R.V.D., Antolin, P., Wedemeyer, S., Vissers, G., Kontar, E.P. and Gallagher, P.T., 2016. Observing the formation of flare-driven coronal rain. The Astrophysical Journal, 833(2), p.184.
15. [15] Şahin, S. and Antolin, P., 2024. From chromospheric evaporation to coronal rain: an investigation of the mass and energy cycle of a flare. The Astrophysical Journal, 970(2), p.106.
16. [16] Mason, E.I., Antiochos, S.K. and Viall, N.M., 2019. Observations of solar coronal rain in null point topologies. The Astrophysical Journal Letters, 874(2), p.L33.
17. [17] Şahin, S. and Antolin, P., 2025. Do Flares Impact Neighboring Quiescent Coronal Rain?. Solar Physics, 300(11), p.158.
18. [18] van Driel-Gesztelyi, L. and Green, L.M., 2015. Evolution of active regions. Living Reviews in Solar Physics, 12(1), p.1.
19. [19] McIntosh, P.S., 1990. The classification of sunspot groups. Solar Physics, 125(2), pp.251-267.
20. [20] Mason, E.I. and Kniezewski, K.L., 2022. To rain or not to rain: correlating GOES flare class and coronal rain statistics. The Astrophysical Journal, 939(1), p.21.
21. [21] Reep, J.W., Benavitz, L.F., To, A.S., Brooks, D.H., Laming, J.M., Antolin, P., Long, D.M. and Baker, D., 2025. Radiative hydrodynamic simulations of FIP fractionation in solar flares. arXiv preprint arXiv:2509.25695.
22. [22] Şahin, S., Antolin, P., Froment, C. and Schad, T.A., 2023. Spatial and temporal analysis of quiescent coronal rain over an active region. The Astrophysical Journal, 950(2), p.171.
23. [23] Şahin, S. and Antolin, P., 2022. Prevalence of thermal nonequilibrium over an active region. The Astrophysical Journal Letters, 931(2), p.L27.
24. [24] Reep, J.W., Warren, H.P., Crump, N.A. and Simões, P.J., 2016. Transition region and chromospheric signatures of impulsive heating events. II. Modeling. The Astrophysical Journal, 827(2), p.145.
25. [25] Toriumi, S. and Wang, H., 2019. Flare-productive active regions. Living Reviews in Solar Physics, 16(1), p.3.
26. [26] Froment, C., Auchère, F., Mikić, Z., Aulanier, G., Bocchialini, K., Buchlin, E., Solomon, J. and Soubrié, E., 2018. On the occurrence of thermal nonequilibrium in coronal loops. The Astrophysical Journal, 855(1), p.52.
27. [27] Li, L., Peter, H., Chitta, L.P. and Song, H., 2020. Relation of coronal rain originating from coronal condensations to interchange magnetic reconnection. The Astrophysical Journal, 905(1), p.26.
28. [28] Qiao, F., Li, L., Tian, H., Hou, Z., Song, H., Ji, K. and Sun, Z., 2024. Three types of solar coronal rain during magnetic reconnection between open and closed magnetic structures. The Astrophysical Journal, 973(1), p.57.
29. [29] Keppens, R., Zhou, Y. and Xia, C., 2025. Modeling multiphase plasma in the corona: prominences and rain: R. Keppens et al. Living Reviews in Solar Physics, 22(1), p.4.
30. [30] Antolin, P. and Rouppe van der Voort, L., 2012. Observing the fine structure of loops through high-resolution spectroscopic observations of coronal rain with the CRISP instrument at the Swedish Solar Telescope. The Astrophysical Journal, 745(2), p.152.
31. [31] Janssens, J., Delouille, V., Clette, F. and Andries, J., 2025. Solar flare rates and probabilities based on the McIntosh classification: Impacts of GOES/XRS rescaling and revisited sunspot classifications. Journal of Space Weather and Space Climate, 15, p.14.
32. [32] Auchère, F., Froment, C., Soubrié, E., Antolin, P., Oliver, R. and Pelouze, G., 2018. The coronal monsoon: thermal nonequilibrium revealed by periodic coronal rain. The Astrophysical Journal, 853(2), p.176.
33. [33] Froment, C., Auchère, F., Bocchialini, K., Buchlin, E., Guennou, C. and Solomon, J., 2015. Evidence for evaporation-incomplete condensation cycles in warm solar coronal loops. The Astrophysical Journal, 807(2), p.158.
34. [34] Johnston, C.D., Cargill, P.J., Antolin, P., Hood, A.W., De Moortel, I. and Bradshaw, S.J., 2019. The effects of numerical resolution, heating timescales and background heating on thermal non-equilibrium in coronal loops. Astronomy & Astrophysics, 625, p.A149.
35. [35] Klimchuk, J.A. and Luna, M., 2019. The role of asymmetries in thermal nonequilibrium. The Astrophysical Journal, 884(1), p.68.
36. [36] Müller, D.A.N., Hansteen, V.H. and Peter, H., 2003. Dynamics of solar coronal loops-I. Condensation in cool loops and its effect on transition region lines. Astronomy & Astrophysics, 411(3), pp.605-613.