Abstract
Solar flare activity is characterized by different classification systems, both in optical and X-ray ranges. The most generally accepted classifications of solar flares describe important parameters of flares such as the maximum of brightness of the flare in the optical range – \(H_{\alpha }\) flare class (change from F to B), area of the flare in \(H_{\alpha }\) (change from S for areas less than 2 square degrees to 4 for areas more than 24.7 square degrees) and the maximum amplitude of the soft X-ray (SXR)-flux in the band 0.1–0.8 nm (\(F_{0.1-0.8}^{\mathrm{max}}\)) – X-ray flares of classes from C to X. A new classification parameter of solar flares is proposed here – the X-ray index of flare XI, based on GOES measurements of solar radiation in the SXR-range. The XI-index has a clear physical interpretation associated with the total flare energy in the SXR-range. XI is easily calculated for each flare with the use of available GOES data. The XI-index can be used along with other geoeffective parameters of Solar activity to assess both flares and coronal mass ejections that are connected with them.
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References
Altyntsev A. T., Banin V. G., Kuklin G. V., Tomozov V. V. 1982, Solar Flares, Nauka, Moscow
Aschwanden M. J. 2005, Physics of the Solar Corona, Springer, Berlin
Bazilevskaya G. A., Logachev Yu. I., Vashenyuk E. V. et al. 2015, Bull. Russian Acad. Sci.: Phys., 79, 627
Belov A., Garcia N., Kurt V. et al. 2005, Solar Phys., 229, 135
Bogod V. M. 2006, Bull. Russian Acad. Sci.: Phys., 70, 491
Bogod V. M. 2011, Astrophys. Bull., 66, 190
Bowen T. A., Testa P., Reeves K. K. 2013a, LWS/SDO Science Workshop (SOC), Cambridge, USA
Bowen T. A., Testa P., Reeves K. K. 2013b, Astrophys. J., 770, 126
Bruevich E. A., Yakunina G. V. 2017, Astrophys., 60, 387
Bruevich E. A., Bruevich V. V. 2018, Astrophys., 61, 241
Gopalswamy N. A. 2004, Astrophys. Space Sci. Libr., 317, 201
Gopalswamy N., Yashiro S., Michalek G., Stenborg G., Vourlidas A., Freeland S., Howard R. 2009, Earth Moon Planet., 104, 295
Gopalswamy N. 2016, Geosci. Lett., 3, article id. 8, 18
Kleczek J. 1952, Publ. Czech Centr. Astron. Inst., 22, 1
Klein K.-L., Krucker S., Trottet G., Hoang S. 2005, Astron. Astrophys., 431, 1047
Li C., Firoz K. A., Sun L. P., Miroshnichenko L. I. 2013, ApJ, 770, article id. 34, 12
Ozgus A., Atac T., Rybak J. 2003, Solar Phys., 214, 375
Preliminary Current Catalogue of Solar Flare Events, 2018, www.wdcb.ru/stp/data/Solar_Flare_Events/Fl_XXIV.pdf
Podgorny I. M., Vashenyuk E. V., Podgorny A. I. 2009, Geomagn. Aeronom., 49, 1115
Reames D. V. 2004, Adv. Space Res., 34(2), 381
Sharykin I. N., Struminsky A. B., Zimovetz I. V. 2012, Astron. Lett., 38, 672
Somov B. V., Syrovatskii S. I. 1976, Sov. Phys. Uspekhi, 19, 813
Struminskii A. B. 2011, Bull. Russian Acad. Sci. Phys., 75, 751
The Catalogue of Solar Flare Events, 2008, www.wdcb.ru/stp/data/Solar_Flare_Events/Fl_XXIII.pdf
Tylka A., Cohen W. F., Dietrich M. A. et al. 2005, ApJ, 625, 474
Zhang J., Dere K. P., Howard R. A., Kundu M. R., White S. M. 2001, Astrophys. J., 559, 452
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Bruevich, E.A. New classification parameter of solar flares based on the maximum flux in soft X-rays and on duration of flare. J Astrophys Astron 41, 3 (2020). https://doi.org/10.1007/s12036-020-9623-0
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DOI: https://doi.org/10.1007/s12036-020-9623-0