Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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SOLAR MICROWAVE BURSTS AND ELECTRON KINETICS

  • LEE JEONGWOO (Physics Department, New Jersey Institute of Technology) ;
  • BONG SU-CHAN (Astronomy Program, SEES, Seoul National University) ;
  • YUN HONG SIK (Astronomy Program, SEES, Seoul National University)
  • Published : 2003.06.01
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Abstract

Solar flares present a number of radiative characteristics indicative of kinetic processes of high energy particles. Proper understanding of the kinetic processes, however, relies on how well we can separate the acceleration from transport characteristics. In this paper, we discuss microwave and hard X-ray bursts as a powerful tool in investigating the acceleration and transport of high energy electrons. After a brief review of the studies devoted to the kinetic process of solar flare particles, we cast them into a simple formulation which allows us to handle the injection, trap, and precipitation of flare electrons self-consistently. The formulation is then taken as a basis for interpreting and analyzing a set of impulsive and gradual bursts occurred on 2001 April 6 observed with the Owens Valley Solar Array, and HXT/WBS onboard Yohkoh satellite. We quantify the acceleration, trap, and precipitation processes during each burst in terms of relevant time scales, and also determine ambient density and magnetic field. Our result suggests that it should be the acceleration property, in particular, electron pitch angle distribution, rather than the trap condition, that is mainly responsible for the distinctive properties of the impulsive and gradual flares.

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References

  1. Aschwanden, M. J. 1998, Deconvolution of Directly Precipitating and Trap-precipitating Electrons in Solar Flare Hard X-Rays. I. Method and Tests, ApJ, 502, 455 https://doi.org/10.1086/305890
  2. Aschwanden, M. J. 2003, Particle Acceleration and Kinematics in Solar Flares, SPACE SCIENCE REVIEWS, Volume 101, Kluwer Academic Publishers, Dordrecht
  3. Aschwanden, M. J., & Alexander, D. 2001, Flare Plasma Cooling from 30 MK down to 1 MK modeled from Yohkoh, GOES, and TRACE observations during the Bastille Day Event (14 July 2000), Sol. Phys., 204, 93
  4. Aschwanden, M. J., Bynum, R. T., Kosugi, T., Hudson, H., and Schwartz, R.A. 1997, Electron Trapping Times and Trap Densities in Solar Flare Loops Measured with Compton and YOHKOH, ApJ, 487, 936 https://doi.org/10.1086/304633
  5. Aschwanden, M. J., Schwartz, R. A., & Dennis, B. R. 1998, Deconvolution of Directly Precipitating and Trap-precipitating Electrons in Solar Flare Hard X-Rays. II. Compton Gamma Ray Observatory Data Analysis, ApJ, 502, 468 https://doi.org/10.1086/305891
  6. Aschwanden, M. J., Fletcher, L., Sakao, T., Kosugi, T. & Hudson, H. 1999, Deconvolution of Directly Precipitating and Trap-precipitating Electrons in Solar Flare Hard X-Rays. III. Yohkoh Hard X-Ray Telescope Data Analysisi, ApJ, 515, 842 https://doi.org/10.1086/307036
  7. Bai, T. 1982, Transport of energetic electrons in a fully ionized hydrogen plasma, ApJ, 308, 912 https://doi.org/10.1086/164561
  8. Bai, T. 1986, Two classes of gamma-ray/Proton flares - Impulsive and gradual, ApJ, 308, 912 https://doi.org/10.1086/164561
  9. Bai, T. & Ramaty, R. 1979, Hard X-ray time profiles and acceleration processes in large solar flares, ApJ, 227, 1072 https://doi.org/10.1086/156814
  10. Bai, T. & Sturrock, P. A., 1989, Classification of solar flares, ARA&A, 27, 421 https://doi.org/10.1146/annurev.aa.27.090189.002225
  11. Bruggmann, G., Vilmer, N., Klein, K.-L., & Kane, S. R. 1994, Electron trapping in evolving coronal structures during a large gradual hard X-ray/radio burs, Sol. Phys., 149, 171 https://doi.org/10.1007/BF00645188
  12. Cornell, M. E., Hurford, G. J., Kiplinger, A. L., & Dennis, B. R. 1984, The relative timing of microwaves and hard X-rays in solar flares, ApJ, 279, 875 https://doi.org/10.1086/161958
  13. Crannell, C. J., Frost, K. J., Saba, J. L., Maetzler, C. & Ohki, K. 1978, Impulsive solar X-ray bursts, ApJ, 223, 620 https://doi.org/10.1086/156297
  14. Ding, M. D., Qiu, J., & Wang, H. 2002, Non-LTE Calculation of the Ni I 676.8 Nanometer Line in a Flaring Atmosphere, ApJ, 576, L83 https://doi.org/10.1086/343103
  15. Fleishman, G. D. & Melnikov, V. F. 2003, Gyrosynchrotron Emission from Anisotropic Electron Distribution, ApJ, 587, 823 https://doi.org/10.1086/368252
  16. Gary, D. E. & Hurford, G. J. 1999, OVRO Solar Array Upgrades in Preparation for MAX 2000 in Proceedings of the Nobeyama Symposium, held in Kiyosato, Japan,.0ct. 27-30, 1998, (Eds.) T. S. Bastian, N. Gopalswamy and K. Shibasaki, NRO Report No. 479., p.429-432
  17. Hamilton, R. J. & Petrosian, V. 1992, Stpchastic acceleration of electrons. I - Effects of collisions in solar flares, ApJ, 398, 350 https://doi.org/10.1086/171860
  18. Hanaoka, Y. 1996, Flares and Plasma Flow Caused by Interacting Coronal Loops, Sol. Phys., 165, 275 https://doi.org/10.1007/BF00149715
  19. Hanaoka, Y. 1997, Double-Loop Conflguration of Solar Flares, Sol. Phys., 173, 319 https://doi.org/10.1023/A:1004953003558
  20. Holman, G. D. 1985, Acceleration ofrunaway electrons and Joule heating in solar flares, ApJ, 293, 584 https://doi.org/10.1086/163263
  21. Holman, G. D., Kundu, M. R., & Papadopoulos, P. 1982, Electron pitch angle scattering and the impulsive phase microwave and hard X-ray emissioii from solar flares, ApJ, 257, 354 https://doi.org/10.1086/159994
  22. Kai., K. 1986, Can observed hard X-ray and microwave flux from solar flares be explained by a single electron population?, Sol. Phys., 104, 235 https://doi.org/10.1007/BF00159967
  23. Kai, K. Kosugi, T., & Nitta, N. 1985, Flux relations between hard X-rays and microwaves for both impulsive and extended solar flares, PASP, 37, 155
  24. Kemiel, C. F. & Petscheck, H. E. 1966, Limit on stably trapped particle fluxes, J. Geophys. Res., 71, 1 https://doi.org/10.1029/JZ071i001p00001
  25. Klein, K.-L., Trottet, G., & Magun, A. 1986, Microwave diagnostics of energetic electrons in flare, Sol. Phys., 104, 243 https://doi.org/10.1007/BF00159969
  26. Kosugi, T., Dennis, B. R., & Kai, K. 1988, Energetic electrons in impulsive and extended solar flares as deduced from flux correlations between hard X-rays and microwave, ApJ, 324, 1118 https://doi.org/10.1086/165967
  27. Kosugi, T., Masuda, S., Makishima, K., Inda, M., Murakami, T., Dotani, T., Ogawara, Y., Sakao, T., Kai, K., & Nakajima, H. 1991, The hard X-ray telescope (HXT) for the Solar-A mission, Sol. Phys., 136, 17 https://doi.org/10.1007/BF00151693
  28. Kundu, M. R., White, S. M., Shibasaki, K., Sakurai, T., & Grechmev, V. V. 2001a, Spatial Structure of Simple Spiky Bursts at Microwave/Millimeter Wavelengths, ApJ, 547, 1090 https://doi.org/10.1086/318422
  29. Kundu, M. R., Grechnev, V. V., Garaimov, V. I., & White, S. M. 2001b, Double Loop Configuration of a Flaring Region from Microwave, Extreme Ultraviolet, and X-Ray Imaging Data, ApJ, 563, 389 https://doi.org/10.1086/323885
  30. Kundu, M. R., Nitta, N., White, S. M., Shibasaki, K., Enome, S., Sakao, T., Kosugi, T., & Sakurai, T. 1995, Microwave and Hard X-Ray Observations of Footpoint Emission from Solar Flares, ApJ, 454, 522 https://doi.org/10.1086/176503
  31. Lee, J. & Gary, D. E. 1994, Spectral evolution of microwaves and hard X-rays in the 1989 March 18 flare and its interpretation, Sol. Phys., 153, 347 https://doi.org/10.1007/BF00712510
  32. Lee, J. & Gary, D. E. 2000, Solar Microwave Bursts and Injection Pitch-Angle Distribution of Flare Electrons, ApJ, 543, 457 https://doi.org/10.1086/317080
  33. Lee, J., Gary, D. E., & Zirin, H. 1994, Flat microwave spectra seen at X-class flare, Sol. Phys., 152, 409 https://doi.org/10.1007/BF00680447
  34. Lee, J., Gary, D. E., & Shibasaki, K. 2000, Magnetic Trapping and Electron Injection in Two Contrasting Solar Microwave Bursts, ApJ, 531, 1109 https://doi.org/10.1086/308511
  35. Lee, J., Gary, D. E., Qiu, J., & Gallagher, P. T. 2002, Electron Transport during the 1999 August 20 Flare Inferred from Microwave and Hard X-Ray Observations, ApJ, 572, 609 https://doi.org/10.1086/340311
  36. Lee, J., Gallagher, P. T., Gary, D. E., Nita, G. M., Choe, G. S., Bong, S.-C., & Yun, H. S. 2003, Halpha;, Extreme-Ultraviolet, and Microwave Obser vations of the 2000 March 22 Solar Flare and Spontaneous Magnetic Reconnection, ApJ, 585, 524 https://doi.org/10.1086/346024
  37. Litvinenko, Y. E. 1996, Particle Acceleration in Reconnecting Current Sheets with a Nonzero Magnetic Field, ApJ, 462, 997 https://doi.org/10.1086/177213
  38. Lu, E. T. and Petrosian, V. 1988, Rapid temporal evolution of radiation from nothermal electrons in solar flares, ApJ, 327, 405 https://doi.org/10.1086/166203
  39. MacKinnon, A. L. 1991, Collisional scattehng of fast electrons in a coronal magnetic bottle, A&A, 242, 256
  40. Marsh, K. A. & Hurford, G. J., 1982, High spatial resolution solar microwave observations, ARA&A, 20, 497 https://doi.org/10.1146/annurev.aa.20.090182.002433
  41. Melnikov, V. F. 1990, Relationships between Microwave, Hard X ray, and Corpuscular Emissions of Solar Flares, Ph.D. Thesis, Radiophysical Research Institute, Nizhniy Novgorod, Russia
  42. Melnikov, V. F. 1994, Particle Acceleration and Capturing in Impulsive and Gradual Bursts, Radiophys. Quant. Electron. 37, 557
  43. Melnikov, V. F. & Magun, A. 1998, Spectral Flattening During Solar Radio Bursts At Cm-mm Wavelengths and the Dynamics of Energetic Electrons in a Flare Loop, Sol. Phys., 178, 153 https://doi.org/10.1023/A:1004944812520
  44. Melnikov, V. F., Shibasaki, K., & Reznikova, V. E. 2002, Loop-Top Nonthermal Microwave Source in Extended Solar Flaring Loops, ApJ, 580, L85 https://doi.org/10.1086/345548
  45. Melrose, D. B. 1980, Plasma Astrophysics, (New York Gordon and Breach)
  46. Melrose, D. B. & Brown, J. C. 1976, Precipitation in trap models for solar hard X-ray bursts, MNRAS, 176, 15 https://doi.org/10.1093/mnras/176.1.15
  47. Miller, J. A. & Steinacker, J. 1992, Stochastic gyroresonant electron acceleration on a low-beta plasma. II - Implications of thermal effects in a solar flare plasma, ApJ, 399, 284 https://doi.org/10.1086/171923
  48. Miller, J. A., Cargill, P. J., Emslie, A. G., Holman, G. D., Dennis, B. R., LaRosa, T. N., Winglee, R. M., Benka, S. G., & Tsuneta, S. 1997, Critical Issues For Understanding Particle Acceleration in Impulsive Solar Flares, J. Geophys. Res., 102, 14631 https://doi.org/10.1029/97JA00976
  49. Moghaddam-Taaheri, E. & Goertz, C. K. 1990, Acceleration of runaway electrons in solar flares, ApJ, 352, 361 https://doi.org/10.1086/168543
  50. Nishio, M., Yaji, K., Kosugi, T., Nakajima, H., & Sakurai, T. 1997, Magnetic Field Configuration in Impulsive Solar Flares Inferred from Coaligned Microwave/X-Ray Images, ApJ, 489, 976 https://doi.org/10.1086/304793
  51. Petrosian, V. 1982, Structure of the impulsive phase of solar flares from microwave observations, ApJ, 255, L85 https://doi.org/10.1086/183774
  52. Petrosian, V. 1990, Acceleration, transport of and radiation by electrons in impulsive phase of flares, in Basic plasma processes on the sun (A92-30901 12-92) Dordrecht, Netherlands, Kluwer Academic Publishers, p. 391
  53. Ramaty, R. 1969, Gyrosynchrotron Emission and Absorption in a Magnetoactive Plasma, ApJ, 158, 753 https://doi.org/10.1086/150235
  54. Sakao, T. 1994, Characteristics of solar flare hard X-ray sources as revealed with the Hard X-ray Telescope aboard the Yohkoh satellite, Ph.D. thesis, University of Tokyo
  55. Scherrer, P. H., et al. 1995, The Solar Oscillations Investigation - Michelson Doppler Imager, Sol. Phys., 162, 129 https://doi.org/10.1007/BF00733429
  56. Silva, A. V. R., Wang, H., & Gary, D. E. 2000, Correlation, of Microwave and Hard X-Ray Spectral Parameters, ApJ, 545, 1116 https://doi.org/10.1086/317822
  57. Spitzer, L. 1967, The Physics of Fully Ionized Gases (2d ed., New York: Interscience)
  58. Takakura, T. & Kai. K. 1966, Energy Distribution of Electrons Producing Microwave Impulsive Bursts and X-Ray Bursts from the Sun, PASJ 18, 57
  59. Vilmer, N., Kane, S. R., & Trottet, G. 1982, mpulsive and gradual hard X-ray sources in a solar flare, A&A, 108. 306
  60. Yoshimori, M., Okudaira, K., Hirasima, Y., Igarashi, T., Akasaka, M., Takai, Y., Morimoto, K., Watanabe, T., Ohki, K., & Nishimura, J. 1991, The wide band spectrometer on the Solar-A, Sol. Phys., 136, 69 https://doi.org/10.1007/BF00151695
  61. Zirin, H. & Tanaka, K. 1981, Magnetic transients in Bares, ApJ, 250, 791 https://doi.org/10.1086/159429