مشاهده نوسان‌های بسیار طولانی پیش‌شراره‌ای، برای دوازده شراره خورشیدی، به‌‌‌عنوان یک نشانه وقوع شراره

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد، دانشکده فیزیک، دانشگاه پیام نور، تهران، ایران

2 استادیار، دانشکده فیزیک، دانشگاه پیام نور، تهران، ایران (صندوق پستی ۳۶۹۷- ۱۹۳۹۵)

چکیده

شراره‌های خورشیدی طغیان‌های ناگهانی در جو خورشید هستند که تابش‌هایی در طول‌موج‌های رادیویی تا اشعه گاما دارند و با توجه به انرژی‌شان در کلاس‌های مختلف (به‌‌‌ترتیب A, B, C, M, X) طبقه‌بندی می‌شوند. پیش‌بینی زمان وقوع یک شراره و مشخص کردن نوع کلاس آن می‌تواند به کم‌کردن اثرات مخرب آن بر روی زمین کمک کند. یکی از فرایندهای پیش از وقوع شراره که می‌‌تواند به پیش‌بینی وقوع آن کمک کند نوسانات با دوره‌تناوب طولانی (VLP) در فاز پیش‌شراره است که نخستین بار توسط تان و همکاران (2016) گزارش شد.
ما در این مقاله با استفاده از داده‌های ماهواره گوس (GOES)، هجده شراره را به‌‌‌لحاظ وقوع VLPهای پیش­شراره انتخاب و بررسی کردیم که ۶ شراره در کلاس  Cو ۱۲ شراره در کلاس M هستند. از این میان در دوازده مورد از آنها VLPهای منظم را پیش از وقوع شراره مشاهده کردیم که به‌‌‌جز یکی بقیه در کلاس M بودند. دوره‌تناوبی که برای VLPهای این شراره ها با کمک تبدیل فوریه ی سریع، محاسبه کردیم ۱۴ تا 9/28 دقیقه است که با نتایج تان و همکاران (۲۰۱۶) در توافق است. تعداد پالس­های مشاهده‌ شده در هر پیش شراره بین ۳ تا ۷ عدد است. برای شش شراره دیگرِ باقی مانده از مجموعه منتخب ما، نیز VLP منظمی مشاهده نشد، که آنها به‌‌‌جز یک مورد همه در کلاس C بودند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Observing of Pre-flare Very Long-period Pulsations, for 12 Solar Flares, as a Sign of Flare’s Onset

نویسندگان [English]

  • Malihe Jalali Rad 1
  • Narges Fathalian 2
1 M.Sc. Student, Department of Physics, Payame Noor University, Tehran, Iran
2 Assistant Professor, Department of Physics, Payame Noor University, Tehran, Iran (P.O.Box 19395-3697)
چکیده [English]

Solar flares are sudden bursts in the solar atmosphere, which have emissions, from radio wavelengths up to gamma rays, and according to their energy are classified into different classes (A, B, C, M, and X, respectively). The process of releasing magnetic energy in flares is done by magnetic reconnection, which is often created by a complex magnetic field. Flares accelerate many electrons and ions, raising their energy to the limit of relative energy. These accelerating particles play a very important role in the release of large solar flare energies. Considering the fact that flares emit radiation when they explode, most of them create light spectrum and sometimes X-rays and ultraviolet rays, which are emitted mainly by the photosphere and chromosphere into concentrated sources called footpoints and ribbons. These radiations and emissions occur when the lower layers of the sun's atmosphere heat up during a flare, and this heating due to the collision of particles probably plays an important role in the occurrence of the flare. In addition, they emit high-energy radiation such as hard X-rays (HXR) from electrons and gamma rays from ions. The main part of these emissions is in the form of electromagnetic emission (soft X-rays) and energetic particles. Emissions radiated from a large flare or a solar mass eruption (with an energy more than J), when reaching the earth, can have destructive effects on the Earth's atmosphere, as well as the orbits of satellites or magnetic and electrical facilities of devices like ships and airplanes. Therefore, predicting the time of the flare occurrence and determining its class type can help reduce these destructive effects.
One of the observable structures that can be seen before a flare occurs, are oscillations with very long period pulsations (VLPs) of the order of 8-30 minutes, which occur about one to two hours before the flare onset, and were first reported by Tan et al. (2016) in the pre-flare phase. MHD oscillations and longitudinal electric current in flare loops can be appropriate candidates to explain the formation of VLPs. Investigating pre-flare VLPs can also help us in understanding the origin of flares. With the help of observational data of X-ray radiation (SXR), onboard the GOES satellite, during the pre-flare phase, these pulses can be observed at similar time scales during flare processes.
In this paper, using the abovementioned data, we selected eighteen flares for the study of which 6 flares are in class C and 12 flares are in class M. Of these, twelve had typical VLPs before flare-onset, which were all in the M class, with the exception of one. The periodicity that we calculated for the VLPs of these flares, with the help of the Fast Fourier Transform is 14 to 28.9 minutes, which is in agreement with the results of Tan et al. (2016). The number of pulses observed in each pre-flare is between 3 and 7. For the other six remaining flares of our selection, no typical pre-flare VLP was observed, which all but one of them, were in class C.

کلیدواژه‌ها [English]

  • Flare
  • Pre-flare Phase
  • Flare Forecast
  • Pre-flare Very Long-period Pulsations
  • GOES data
Alfven, H. and Carlqvist, P., 1967, Currents in the Solar Atmosphere and a Theory of Solar Flares, So.Ph., 1, 220.
Benz, A. O., 2017, Flare Observations, Living Reviews in Solar Physics, 14, 2.
Foullon, C., Verwichte, E., Nakariakov, V. M. and Fletcher, L., 2005, X-ray quasi-periodic pulsations in solar flares as magnetohydrodynamic oscillations, A&A, 440, L59.
Hannah, G., Hudson, H. S., Battaglia, M., Christe, S., Kaˇsparova´, J., Krucker, S., Kundu, M. R. and Veronig, A., 2011, Microflares and the Statistics of X-ray Flares, Space Science Revs, 159, 263, 1108.6203, doi:10.1007/s11214-010-9705-4.
Harrison, R. A., 1987, Solar soft X-ray pulsations, A&A, 182, 337.
Hayes, L. A., Gallagher, P. T., Dennis, B. R., Ireland, J., Inglis, A. and Morosan, D. E., 2019, Persistent Quasi-periodic Pulsations during a Large X-class Solar Flare,  ApJ, 875, 33.
Inglis, A. R., Ireland, J., Dennis, B. R., Hayes, L. and Gallagher, P., 2016, A Large-scale Search for Evidence of Quasi-periodic Pulsations in Solar Flare, ApJ, 833, 284.
Kolotkov, D. Y., Nakariakov, V. M., Kupriyanova, E. G., Ratcliffe, H. and Shibasaki, K., 2015, Multi-mode quasi-periodic pulsations in a solar flare, A&A, 574, A53.
Kumar, S., Nakariakov, V. M. and Moon, Y.J, 2016, Effect of a Radiation Cooling and Heating Function on Standing Longitudinal Oscillations in Coronal Loops, ApJ, 824, 8.
Li, D., Zhang, Q. M., Huang, Y., Ning, Z. J. and Su, Y. N., 2017, Quasi-periodic pulsations with periods that change depending on whether the pulsations have thermal or nonthermal components, A&A 597,L4.
Li, D., Li, Y., Lu, L., Zhang, Q., Ning, Z. and Anfinogentov, S., 2020a, HYPERLINK "https://ui.adsabs.harvard.edu/"Observations of a Quasi-periodic Pulsation in the Coronal Loop and Microwave Flux during a Solar Preflare Phase, ApJ, 893, L17.
Li, D., Lu, L., Ning, Z., Feng, L., Gan, W. and Li, H., 2020b, HYPERLINK "https://ui.adsabs.harvard.edu/"Quasi-periodic Pulsation Detected in Lyα Emission During Solar Flares, ApJ, 893, 7.
Li, D., Feng, S., Su, W. and Huang, Y., 2020c, Preflare very long-periodic pulsations observed in H emission before the onset of a solar flare, A&A, 639, L5. https://doi.org/10.1051/0004-6361/202038398.
McLaughlin, J. A., Nakariakov, V. M., Dominique, M., Jelínek, P. and Takasao, S., 2018, Modeling Quasi-Periodic Pulsations in Solar and Stellar Flares, Space Sci. Rev., 214, 45.
Nakariakov, V. M., Kolotkov, D. Y., Kupriyanova, E. G., Mehta, T., Pugh, C. E., Lee, D. H. and Broomhall, A. M., 2018, Non-stationary quasi-periodic pulsations in solar and stellar flares, Plasma Physics and Controlled Fusion, 61, 014024.
Nakariakov, V. M., Kosak, M. K., Kolotkov, D. Y., Anfinogentov, S. A., Kumar, P. and Moon, Y. J., 2019, Properties of Slow Magneto acoustic Oscillations of Solar Coronal Loops by Multi-instrumental Observations, ApJ, 874, L1.
One-Minute Quasi-Periodic Pulsations Seen in a Solar Flare, Sol. Phys., 292, 11.
Priest, E., 2014, Magnetohydrodynamics of the Sun, Cambridge University Press.
Pugh, C. E., Broomhall, A.-M. and Nakariakov, V. M., 2019, Scaling laws of quasi-periodic pulsations in solar flares, A&A, 624, A65.
Shen, Y. D., Liu, Y., Su, J. T., Li, H., Zhang, X. F., Tian, Z. J., Zhao, R. J. and Elmhamdi, A., 2013, Observations of a Quasi-periodic, Fast-Propagating Magnetosonic Wave in Multiple Wavelengths and Its Interaction with Other Magnetic Structures, Sol. Phys., 288, 585.
Svestka, Z., 1994, Slow-mode oscillations of large-scale coronal loops, So.Ph., 152, 505.
Tan, B. L., Ji, H. S., Huang, G. L, Zhou, T. H., Song, Q. W. and Huang, Y., 2006, Evolution of Electric Currents Associated with Two M-Class Flares, So. Ph., 239,137.
Tan, B., Yan, Y., Tan, C. and Liu, Y., 2007, The Microwave Pulsations and the Tearing Modes in the Current-Carrying Flare Loops, ApJ, 671, 964. Tan, B., Yu, Z., Huang, J., Tan, C. and Zhang Y., 2016, Very Long-period Pulsations before the Onset of Solar Flares, ApJ, 833. 206T. (ArXiv:1610.09291v2).
Tian, H., Young, P. R., Reeves, K. K., Wang, O., Antolin, P., Chen, B. and He, J., 2016, Global Sausage Oscillation of Solar Flare Loops Detected by the Interface Region Imaging Spectrograph, ApJ, 823, L16.
Thurgood, J. O., Pontin, D. I. and McLaughlin, J. A., 2017, Three-dimensional Oscillatory Magnetic Reconnection, ApJ, 844, 2.
Tobias, S. M. and Cattaneo, F., 2013, Shear-driven dynamo waves at high magnetic Reynolds number, Nature, 497, 463.
Van Doorsselaere, T., Kupriyanova, E. G. and Yuan, D., 2016, Quasi-periodic Pulsations in Solar and Stellar Flares: An Overview of Recent Results (Invited Review) , Sol. Phys., 291, 3143.
Wang, T. J., 2011, Standing Slow-Mode Waves in Hot Coronal Loops: Observations, Modeling, and Coronal Seismology, Space Sci. Rev., 158, 397.
Wang, T., Ofman, L., Sun, X., Provornikova, E. and Davila, J. M., 2015, Evidence of Thermal Conduction Suppression in a Solar Flaring Loop by Coronal Seismology of Slow-mode Waves, ApJ, 811, L13.
Yu, S. and Chen, B., 2019, Possible Detection of Sub-second-period Propagating Magneto hydrodynamics Waves in Post-reconnection Magnetic Loops during a Two-ribbon Solar Flare, ApJ, 872, 71.
Yuan, D., Nakariakov, V. M., Chorley, N. and Foullon, C., 2011, Leakage of long-period oscillations from the chromosphere to the corona, A&A, 533, 116
Zhou, G. P., Zhang, J. and Wang, J. X., 2016, Observations of Magnetic Flux-rope Oscillation during the Precursor Phase of a Solar Eruption, ApJ, 823, L19.