Fe XVIII EMISSION LINES IN SOLAR X-RAY SPECTRA

被引:0
|
作者
G. A. WARREN
F. P. KEENAN
C. J. GREER
K. J. H. PHILLIPS
M. E. BRUNER
W. A. BROWN
D. L. McKENZIE
机构
[1] The Queen's University of Belfast,Department of Pure and Applied Physics
[2] Rutherford Appleton Laboratory,Astrophysics Division
[3] Chilton,Space and Environment Technology Center
[4] Didcot,undefined
[5] Lockheed Palto Alto Research Laboratory,undefined
[6] The Aerospace Corporation,undefined
来源
Solar Physics | 1997年 / 171卷
关键词
Flare; Wavelength Range; Emission Line; Electron Temperature; Solar Corona;
D O I
暂无
中图分类号
学科分类号
摘要
We have calculated intensity ratios for emission lines of Fexviii in the 13–94 Å wavelength range at electron temperatures characteristic of the solar corona, Te = 2–10 x 106 K. Our model ion includes data for transitions among the 2s22p5 , 2s2p6, 2s22p43l, and 2s2p53l (l = s, p, and d) states. Test calculations which omit the 2s2p53l levels show that cascades from these are important. We compare our results with observed ratios determined from four solar X-ray instruments, a rocket-borne spectrograph, and spectrometers on the P78–1, OV1–17 and Solar Maximum Mission (SMM) satellites. In addition, we have generated synthetic spectra which we compare directly with flare observations from SMM. Agreement between theory and observation is generally quite good, with differences that are mostly less than 30%, providing limited support for the accuracy of the atomic physics data used in our calculations. However, large discrepancies are found for ratios involving the 2s22p52P3/2- 2s2p62S line at 93.84 Å, which currently remain unexplained. Our analysis indicates that the FeXVIII feature at 15.83 Å is the 2s22p52P3/2 - 2s22p4(3P)3s 4P3/2 transition, rather than 2s22p52P3/2 - 2s22p4(3P)3s 2P3/2, as suggested by some authors.
引用
收藏
页码:93 / 102
页数:9
相关论文
共 50 条
  • [1] Fe XVIII emission lines in solar X-ray spectra
    Warren, GA
    Keenan, FP
    Greer, CJ
    Phillips, KJH
    Bruner, ME
    Brown, WA
    McKenzie, DL
    SOLAR PHYSICS, 1997, 171 (01) : 93 - 102
  • [2] Soft X-ray emission lines of Ni XVIII in the solar spectrum
    Keenan, FP
    Mathioudakis, M
    Pinfield, DJ
    Brown, WA
    Bruner, ME
    SOLAR PHYSICS, 1999, 185 (02) : 289 - 296
  • [3] Soft X-ray emission lines of Ni XVIII in the solar spectrum
    F.P. Keenan
    M. Mathioudakis
    D.J. Pinfield
    W.A. Brown
    M.E. Bruner
    Solar Physics, 1999, 185 : 289 - 296
  • [4] Fe x emission lines in solar and stellar spectra
    Foster, VJ
    Mathioudakis, M
    Keenan, FP
    Drake, JJ
    Widing, KG
    ASTROPHYSICAL JOURNAL, 1996, 473 (01): : 560 - 564
  • [6] Soft X-ray emission lines of Fe XV in spectra of the Sun and Capella
    Drake, JJ
    Keenan, FP
    Chung, S
    Brickhouse, NS
    Aggarwal, KM
    Msezane, AZ
    Ryans, RSI
    Bloomfield, DS
    X-RAY DIAGNOSTICS OF ASTROPHYSICAL PLASMAS: THEORY, EXPERIMENT, AND OBSERVATION, 2005, 774 : 349 - 352
  • [7] An investigation of Fe XVI emission lines in solar and stellar extreme-ultraviolet and soft X-ray spectra
    Keenan, F. P.
    Drake, J. J.
    Aggarwal, K. M.
    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2007, 381 (04) : 1727 - 1732
  • [8] CLASSIFICATION OF FE XVIII TO XXIV EMISSION-LINES IN SOLAR-FLARE SPECTRA
    FAWCETT, BC
    SPACE SCIENCE REVIEWS, 1972, 13 (4-6) : 763 - &
  • [9] Emission lines in X-ray spectra of clusters of galaxies
    Tozzi, Paolo
    SPECTRAL LINE SHAPES IN ASTROPHYSICS, 2007, 938 : 43 - 50
  • [10] OBSERVATION AND ANALYSIS OF FE-XVIII SOLAR X-RAY-EMISSION
    RUGGE, HR
    WALKER, ABC
    ASTROPHYSICAL JOURNAL, 1978, 219 (03): : 1068 - 1078