Subflares and surges in AR 2744 during the Solar Maximum Mission

被引:0
作者
Schmieder, B
Rovira, M
Simnett, GM
Fontenla, JM
TandbergHanssen, E
机构
[1] INST ASTRON & FIS ESPACIO, RA-1428 BUENOS AIRES, DF, ARGENTINA
[2] UNIV BIRMINGHAM, BIRMINGHAM B15 2TT, W MIDLANDS, ENGLAND
[3] NCAR, HAO, BOULDER, CO 80027 USA
[4] NASA, GEORGE C MARSHALL SPACE FLIGHT CTR, DIV SPACE SCI, HUNTSVILLE, AL 35812 USA
关键词
Sun; activity; flares; X-rays;
D O I
暂无
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Active region NOAA 2744, which was at S25, had its central meridian passage on Oct 23 1980 and was relatively quiet according to H alpha, UV and X-ray observations made by the Solar Maximum Mission (SMM), The region was also observed by the Marshall Space Flight Center (MSFC) vector magnetograph. During its disk passage only subflares and surges were detected. Their locations appeared to be governed by the magnetic topology. On October 21 a miniflare occurred close to the separator between the two main sunspots. On October 22 the emergence of a small region of parasitic polarity in the existing magnetic field appeared to be responsible for three subflares and subsequent surges. We discuss the energy budget for plasmas at temperatures in the 10(4) K, 10(5) K and 10(6) K ranges in the context of surge-trigger mechanisms. On October 21 the energy deposition driving the surges did not produce a high temperature plasma. By October 22 the active region had evolved and the surges were now associated with some high temperature plasma. However, the energy radiated at transition region temperatures would be larger than that estimated in X-rays depending on the dilution factor. This would imply a continuous influx of energy in order to sustain the long duration surge (30 min) rather than a simple, impulsive energy input. If the electron density in the 10(4)-10(5) K plasma is taken as similar to 10(12) cm(-3) the diameter of individual surge loops should only be similar to 40 km. The relevance of our results to (a) reconnection and (b) gradient pressure driven models for surges is discussed.
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页码:957 / 969
页数:13
相关论文
共 25 条
  • [1] OBSERVATION BY ULYSSES OF HOT (SIMILAR-TO-270 KEV) CORONAL PARTICLES AT 32-DEGREES SOUTH HELIOLATITUDE AND 4.6 AU
    ARMSTRONG, TP
    HAGGERTY, D
    LANZEROTTI, LJ
    MACLENNAN, CG
    ROELOF, EC
    PICK, M
    SIMNETT, GM
    GOLD, RE
    KRIMIGIS, SM
    ANDERSON, KA
    LIN, RP
    SARRIS, ET
    FORSYTH, R
    BALOGH, A
    [J]. GEOPHYSICAL RESEARCH LETTERS, 1994, 21 (17) : 1747 - 1750
  • [2] UNSTABLE CHROMOSPHERIC DARK FEATURES AND TYPE-III BURSTS ASSOCIATION
    CHIUDERIDRAGO, F
    MEIN, N
    PICK, M
    [J]. SOLAR PHYSICS, 1986, 103 (02) : 235 - 247
  • [3] IONIZATION EQUILIBRIUM AND RADIATIVE COOLING OF A LOW-DENSITY PLASMA
    COX, DP
    TUCKER, WH
    [J]. ASTROPHYSICAL JOURNAL, 1969, 157 (3P1) : 1157 - &
  • [4] INTERPRETATION OF MULTIWAVELENGTH OBSERVATIONS OF NOVEMBER 5, 1980 SOLAR-FLARES BY THE MAGNETIC TOPOLOGY OF AR-2766
    DEMOULIN, P
    MANDRINI, CH
    ROVIRA, MG
    HENOUX, JC
    MACHADO, ME
    [J]. SOLAR PHYSICS, 1994, 150 (1-2) : 221 - 243
  • [5] DOYLE JG, 1985, SOL PHYS, V98, P141, DOI 10.1007/BF00177204
  • [6] ENERGY-BALANCE IN THE SOLAR TRANSITION REGION .2. EFFECTS OF PRESSURE AND ENERGY INPUT ON HYDROSTATIC MODELS
    FONTENLA, JM
    AVRETT, EH
    LOESER, R
    [J]. ASTROPHYSICAL JOURNAL, 1991, 377 (02) : 712 - 725
  • [7] FLARING ARCHES .3. THE SUBFLARE OF JUNE 27, 1980, AND ITS RELATED EXTENDED ARCH
    FONTENLA, JM
    SVESTKA, Z
    FARNIK, F
    TANG, FY
    [J]. SOLAR PHYSICS, 1991, 134 (01) : 145 - 169
  • [8] EMERGING FLUX MODEL FOR SOLAR-FLARE PHENOMENON
    HEYVAERTS, J
    PRIEST, ER
    RUST, DM
    [J]. ASTROPHYSICAL JOURNAL, 1977, 216 (01) : 123 - 137
  • [9] AN ANALYSIS OF SURGES TRIGGERED BY A SMALL FLARE
    KOVACS, A
    DEZSO, L
    [J]. SOLAR PHYSICS, 1990, 129 (02) : 313 - 324
  • [10] KOVACS A, 1988, P IRKUTSK SMY WORKSH, P317