Browse > Article
http://dx.doi.org/10.5303/JKAS.2003.36.spc1.055

SPECTRAL DIAGNOSTICS OF NON-THERMAL PARTICLES IN THE SOLAR CHROMOSPHERE  

FANG C. (Department of Astronomy, Nanjing University)
XU Z. (Department of Astronomy, Nanjing University)
DING M. D. (Department of Astronomy, Nanjing University)
Publication Information
Journal of The Korean Astronomical Society / v.36, no.spc1, 2003 , pp. 55-61 More about this Journal
Abstract
There are at least three effects of the non-thermal particle bombardment on the solar atmosphere: (1) non-thermal ionization and excitation; (2) proton-hydrogen charge exchange; (3) impact line polarization. Due to the non-thermal ionization and excitation effects of electron bombardments in flares, H$\alpha$ line is widely broadened and shows a strong central reversal. Significant enhancements at the line wings of Ly$\alpha$ and Ly$\beta$ are also predicted. In the case of proton bombardment, less strong broadening and no large central reversal are expected. However, due to proton-hydrogen charge exchange, the enhancements at the red wings of Ly$\alpha$ and especially of Ly$\beta$ lines at the early impulsive phase of flares are significant. Electron beam can also in some cases generates visible and UV continuum emission in white-light flares. However, at the onset phase, a negative 'black' flare may appear in several seconds, due to the increase of the $H^-$ opacity. The impact polarization of atomic lines can provide complementary information on the energetic particles, the energy transport and deposit in the solar chromosphere. New results of spectropolarimetric analysis for the major flare on July 23, 2002 are also given in the paper.
Keywords
Sun: chromosphere; Sun: particle beam; Line: diagnostics;
Citations & Related Records
연도 인용수 순위
  • Reference
1 H$\noux, J. -C., & Vogt, E. 1998, Physica Scripta, T78, 60
2 Kazantsev, S. A., & H$\noux, J. -C. 1995, Polarization Spectroscopy of Ionized Gases, Kluwer Acad. Publ., Dordrecht
3 Machado, M. E., Avrett, E. H., Vernazza, J. E., & Noyes, R. W. 1980, Semiempirical models of chromospheric flare regions, ApJ, 242, 336   DOI
4 Vernazza, J. E., Avrett, E. H., & Loeser, R. 1981, Structure of the solar chromosphere. III - Models of the EUV brightness components of the quiet-sun, ApJS, 45, 635   DOI
5 Vogt, E., & H$\noux, J. -C. 1996, Polarimetric study of solar flares, Sol. Phys., 164, 345   DOI   ScienceOn
6 Xu, Z., Firstova, N. M., & Fang, C. 2003, Chinese Journal of Astronomy and Astrophys. submitted
7 Zhao, X., Fang, C., & Henoux, J. -C. 1998, Nonthermal hydrogen line emission caused by an oblique incident proton beam through charge exchange, A&A, 330, 351
8 Fang, C., H$\noux, J. -C., & Gan, W. Q. 1993, Diagnostics of non-thermal processes in chromospheric flares I. H$\alpha$ and CaII K line profiles of an atmosphere bombarded by hecta KeV electrons, A&A, 274, 917 (PaperI)
9 Fang, C., Henoux, J. -C., & Ding, M. D. 2000, Diagnostics of non-thermal processes in chromospheric flares IV. limb flare spectra for an atmosphere bombarded by electron beams, A&A, 360, 702
10 Firstova, N. M., H$\noux, J.-C., Kazantsev, S. A., & Bulatov, A. V. 1997, Spectroscopolarimetric Sensing of Energy Deposition Into the Chromosphere during Solar Flares - I. Observations, Sol. Phys., 171, 123   DOI   ScienceOn
11 Firstova, N. M., Xu, Z., & Fang, C. 2003, Ho. line polarization in the major flare of 2002 July 23 I. Observations and Data Analysis, ApJL, accepted
12 H$\noux, J.-C., Chambe, G., Smith, D., Tamres, D., Feautrier, N., Rovira, M., & Sahal-Brechot, S. 1990, Impact line linear polarization as a diagnostic of 100 keV proton acceleration in solar flares, ApJ Suppl., 73, 303   DOI
13 Henoux, J. -C. 1991, in: Solar Polarimetry, NSO/SP Summer Workshop Series, 11, 295
14 H$\noux, J. -C., & Aboudarham, J. 1992, In: Svestka, Z., Jackson, B. V. and Machado, M. E. (eds), Eruptive Solar Flares, Sprmger-Verlag, p.118
15 Aboudarham, J., & H$\noux, J. -C. 1987, Non-thermal excitation and ionization of hydrogen in solar flares. II - Effects on the temperature minimum region Energy balance and white light flares, A&A, 174, 270
16 H$\noux, J. -C., Fang, C., & Gan, W. Q. 1993, Diagnostics of non-thermal processes in chromospheric flares II. H$\alpha$ and CaII K line profiles for an atmosphere bombarded by 100 KeV-l MeV protons, A&A, 274, 923 (Paper II)
17 H$\noux, J. -C., Fang, C., & Gan, W. Q. 1995, Diagnostics of non-thermal processes in chromospheric flares III. Ly$\alpha$ and Ly/$\beta$ spectra for an atmosphere bombarded by electron or proton beams, A&A, 297, 574
18 Aboudarham, J., & H$\noux, J. -C. 1986, Energy deposit at temperature minimum level and white light flares, A&A, 156, 73
19 Canfield, R. C., & Chang, C. R. 1985, Ly-alpha and Halpha emission by superthermal proton beams, ApJ, 295, 275   DOI
20 Chambe, G., & H$\noux, J. -C. 1979, Direct excitation of hydrogen by photoelectron and accelerated electron collisions in solar chromospheric flares - Effects on the profile and polarization of LY alpha, A&A, 80, 123
21 Ding, M. D., & Fang, C. 1996, Parametric study of the continuum emission of white-light flares, A&A, 314, 643
22 Ding, M. D., Fang, C., & Yun, H. S. 1999, Heating in the lower atmosphere and the continuum emission of solar white-light flares, ApJ, 512, 454   DOI   ScienceOn
23 Fang, C, Huang, Y. R, Hu, J., & Gan, W. Q. 1986, Semiempirical timevarying models of chromospheric flares, in D.Neidig (ed.) The Lower Atmosphere of Solar Flares, NSO, Sunspot, NM. p. 117
24 Emslie, A. G. 1978, The collisional interaction of a beam of charged particles with a hydrogen target of arbitrary ionization level, ApJ, 224, 241   DOI
25 Fang, C., Feautrier, N., & Henoux, J. -C. 1995, Hydrogen line spectra of a nonthermal proton beam due to charge exchange in solar flares, A&A, 297, 854