Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://solarwind.cosmos.ru/txt/gma681.pdf Äàòà èçìåíåíèÿ: Tue Dec 20 17:13:58 2005 Äàòà èíäåêñèðîâàíèÿ: Mon Oct 1 19:58:43 2012 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: deep sky

Geomagnetism and Aeronomy, Vol. 45, No. 6, 2005, pp. 681­719. Translated from Geomagnetizm i Aeronomiya, Vol. 45, No. 6, 2005, pp. 723­763. Original Russian Text Copyright © 2005 by Yu. Yermolaev, Zelenyi, Zastenker, Petrukovich, M. Yermolaev, Nikolaeva, Panasyuk, Kuznetsov, Myagkova, Murav'eva, Yushkov, Veselovsky, Dmitriev, Zhukov, Yakovchouk, Kuznetsov, Chertok, Ishkov, Belov, Eroshenko, Yanke, Gaidash, Kanonidi, Kuzin, Zhitnik, Ignat'ev, Slemzin, Sukhodrev, Shestov, M. Eselevich, V. Eselevich, Rudenko, Dvornikov, Sdobnov, Kravtsova, Bogod, Kotel'nikov, Pershakov, Beloglazov, Vlasov, Chashei, Kleimenova, Kozyreva, Kozlov, Parkhomov, Kugaenko, Khisamov, Yanchukovskii, Kudela. English Translation Copyright © 2005 by Pleiades Publishing, Inc.

A Year Later: Solar, Heliospheric, and Magnetospheric Disturbances in November 2004
Yu. I. Yermolaev1, L. M. Zelenyi1, G. N. Zastenker1, A. A. Petrukovich1, M. Yu. Yermolaev1, N. S. Nikolaeva1, M. I. Panasyuk2, S. N. Kuznetsov2, I. N. Myagkova2, E. A. Murav'eva2, B. Yu. Yushkov2, I. S. Veselovsky2, A. V. Dmitriev2, 15, A. N. Zhukov2, 16, O. S. Yakovchouk2, V. D. Kuznetsov3, I. M. Chertok3, V. N. Ishkov3, A. V. Belov3, E. A. Eroshenko3, V. G. Yanke3, S. P. Gaidash3, Kh. D. Kanonidi3, S. V. Kuzin4, I. A. Zhitnik4, A. P. Ignat'ev4, V. A. Slemzin4, N. K. Sukhodrev4, S. A. Shestov4, M. V. Eselevich5, V. G. Eselevich5, G. V. Rudenko5, V. M. Dvornikov5, V. E. Sdobnov5, M. V. Kravtsova5, V. M. Bogod6, V. S. Kotel'nikov6, L. A. Pershakov7, M. I. Beloglazov7, V. I. Vlasov8, I. V. Chashei8, N. G. Kleimenova9, O. V. Kozyreva9, V. I. Kozlov10, V. A. Parkhomov11, Yu. A. Kugaenko12, R. Z. Khisamov13, V. L. Yanchukovskii13, and K. Kudela14
Space Research Institute, Russian Academy of Sciences (IKI RAN), Profsoyuznaya ul. 84/32, Moscow, 117997 Russia 2 Skobeltsyn Research Institute of Nuclear Physics, Moscow State University (NIIYaF MGU), Vorob'evy gory, Moscow, 119899 Russia Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radiowave Propagation, Russian Academy of Sciences, Troitsk, Moscow oblast, 142190 Russia 4 Lebedev Physics Institute, Russian Academy of Sciences (FIAN), Leninskii pr. 53, Moscow, 119991 Russia 5 Institute of Solar­Terrestrial Physics (ISZF), Siberian Division, Russian Academy of Sciences, P.O. Box 4026, Irkutsk, 664033 Russia 6 Special Astronomical (Pulkovo) Observatory, Russian Academy of Sciences, Pulkovskoe sh. 65, St. Petersburg, 196140 Russia 7 Polar Geophysical Institute (PGI), Kola Scientific Center, Russian Academy of Sciences, ul. Fersmana 14, Apatity, Murmansk oblast, 184209 Russia 8 Pushchino Radio Astronomy Observatory, Lebedev Physics Institute, Russian Academy of Sciences, Pushchino, 142292 Russia 9 Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Bol'shaya Gruzinskaya ul. 10, Moscow, 123810 Russia 10 Shafer Institute of Cosmophysical Research and Aeronomy, Siberian Division, Russian Academy of Sciences, pr. Lenina 31, Yakutsk, 677007 Russia 11 Baikal State University of Economics and Law, Irkutsk, Russia 12 Kamchat Branch, Geophysical Service, Russian Academy of Sciences, Petropavlovsk-Kamchatskii, Russia 13 Cosmic Ray Station, Novosibirsk Geophysical Observatory, Geophysical Service, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia 14 Institute of Experimental Physics, Academy of Sciences of Slovakia, Ko¡ice, Slovakia 15 Space Science Institute, Taiwan 16 Belgian Royal Observatory, Brussels, Belgium
Received May 18, 2005; in final form, July 21, 2005
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Abstract--A year after the extreme events on the Sun, in the heliosphere, and on the Earth in October­November 2003 [Veselovsky et al., 2004; Panasyuk et al., 2004; Yermolaev et al., 2005], a similar situation was also observed in November 2004. The main data observed when the strongest magnetic storm with Dst = ­373 nT occurred on the Earth are presented in the paper prepared mainly by the participants of the last year's collaboration of native researchers of extreme events. The disturbance of the Sun, solar wind, and magnetosphere during the considered period was weaker than during the similar period in 2003 with respect to a number of parameters; nevertheless, the presented data indicate that the decline phase of solar cycle 23 is one of the most active intervals over the entire period of comprehensive studies of the solar­terrestrial coupling owing to the events that occurred in autumn 2003 and 2004. 681


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1. INTRODUCTION Studying the effect of solar and interplanetary (heliospheric) events on the near-Earth space is still the most important component of the solar­terrestrial physics. Since such an effect, often called space weather, is important in many areas of human activity, the studies in this direction are developed rapidly. In spite of the fact that the general concept of such an effect has been almost constant for many years and the large body of experimental and theoretical data has been accumulated by the present (see, e.g., the collected volumes and reviews [Gonzalez et al., 1999, 2004; Crooker, 2000; Richardson et al., 2001; Bothmer et al., 2002; Yermolaev and Yermolaev, 2003; Cole, 2003; Lyatsky and Tan, 2003; Daglis et al., 2003; Maltsev, 2004; Echer and Gonzalez, 2004; Yermolaev et al., 2005; Dmitriev et al., 2005; Kane, 2005; Schwenn et al., 2005] and references therein), it is to a certain degree difficult to predict effects of the space weather. In this case it is possible to very accurately predict the response of the magnetosphere and underlying Earth's regions based on measurements of the interplanetary medium parameters near the Earth's magnetosphere (specifically, at the libration point L1); however, the degree of validity of a similar prediction based on solar observations remains rather low [Yermolaev and Yermolaev, 2003; Kane, 2005; Schwenn et al., 2005; Yermolaev et al., 2005]. This is related to the facts that, on the one hand, the studied system is complicated and includes many independent links where different physical mechanisms operate and, on the other hand, the experimental data are limited and are obtained only at certain spatial points that can be reached by up-to-date instrumentation. Therefore, integrated interdisciplinary studies are most promising and are carried out in our country and abroad. An excellent example of such an approach can be a "brain assault" of

the collaboration of the native researchers from more than ten scientific institutions, which was organized by IKI RAN and NIIYaF MGU in order to study the extreme events that occurred on the Sun, in the heliosphere, and on the Earth in October­November 2003. Extensive data on these events were collected over a relatively short time interval; the "International Symposium on Solar Extreme Events of 2003: Fundamental Science and Applied Aspects" was held in Moscow on July 12­14, 2004; and several reviews [Veselovsky et al., 2004; Panasyuk et al., 2004; Yermolaev et al., 2005] and specific papers (see Cosmic Research, no. 6, 2004 and Geomagnetism and Aeronomy, no. 1, 2005) were published. Together with the foreign studies of these events (see the papers in the special issue of the journal Geophysical Research Letters, Vol. 32, no. 12, 2005 and references therein), these results made it possible to substantially progress in understanding the regularities of the solar­terrestrial physics using the extreme events of October­November 2003 as an example. Exactly a year later, at the end of October­beginning of November 2004, the Sun was again very active and generated a number of strong interplanetary and magnetospheric disturbances (Fig. 1, Table 1). The values of some parameters measured during this period of 2004 were slightly smaller than the extreme values observed in 2003 (three X-class solar flares as compared to 11 such flares in 2003 and the magnetic storm with Dst = ­373 nT as compared to the storm with Dst = ­401 nT in 2003); nevertheless, solar activity in 2004 can be considered among the strongest events not only in the current solar activity cycle (cycle 23) but also during the entire period of space observations. The group of researchers, which was mainly formed during an analysis of the previous active period, collected and analyzed new data on the Sun and heliosphere before the magnetic storm of November 8­10, 2004, and on

Table 1. Flare events in AR 10696 in November 2004 and their manifestations in the near-Earth space Ord. no. 1 2 3 4 5 Date, UT, duration (min) Nov. Nov. Nov. Nov. Nov. Nov. Nov. Nov. Nov. Nov. Nov. Nov. 3, 1535, 59 4, 0845, >79 4, 2142, >131 4, 2234 5, 1123, >10 5, 1910 6, 0011, 157 6, 0044 6, 0140 7, 1542, >33 9, 1659, 90 10, 0159, 76 Coordinates N11 E40 N08 E28 N11 E19 N08 E15 N09 E07 N10 E08 Class M5.0/SN C6.3/SN M2.5/1N M5.4/1N M4.0/1F M1.2/SF M9.3/2N M5.9 M3.6 X2.0/2B M8.9/2N X2.5/3B CME NE P.Halo P.Halo P.Halo ­ ­ Halo Halo Halo Halo Halo Halo ISW date/UT 7/0200 7/1000 Magnetic storm date Dst

7/1755 Nov. 8 ­373 nT 9/1818 Nov. 10 ­289 nT
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Ä

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100 0 100 200 300 400 X M 1 35 4 2 6

Dst, nT

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8

C B Nov. 1

Nov. 11

Nov. 21

Dec. 1

Fig. 1. The series of solar and ground-based measurements in November 2004. The upper and middle panels: the Kp and Dst indices (dashed and solid lines are the boundaries of moderate and strong magnetic storms). The Lower panel: the X-ray emission according to the GOES-12 satellite measurements (letters X, M, B, and C on the axis and different lines show flare classes). Nos. 1­8 correspond to the flares presented in Table 1.

the state of the Earth's magnetosphere at that time presented in this work. This work is preliminary, and its aim is to generally describe the state of different spatial regions during that period and to present the main Russian and foreign experimental data that can be used in a further analysis. 2. SOLAR OBSERVATIONS 2.1. General Description of Solar Events The burst of solar-flare and eruptive activity at the decline phase of the current solar cycle (cycle 23) was observed at the end of October­beginning of November 2004. This burst was related to the passage of two sunspot groups­active regions (ARs) 10691 and 10696­ over the visible solar disk. One X-class flare and seven M-class flares occurred in AR 10691 during 38 h from October 30 to November 1. The consequences of this activity in the near-Earth space were rather weak: two proton events of low intensity and a number of sudden ionospheric disturbances of a medium power; however, geomagnetic disturbances were not observed. This was apparently related to the position of the active region relative to the Sun­Earth line since the AR heliolongitude changed from W20 to W60 during this period and potentially effective disturbances could pass over the Earth. Therefore, it is more interesting to analyze the effect of the Sun on the Earth using solar activity in another active region (AR 10696).
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Considered activity was related to a rapid development of AR 10696 (coordinates N09, Carrington longitude L = 026) (Fig. 2). According to the data presented in the Preliminary Report and Forecast of Solar Geophysical Data (see http://www.sel.noaa.gov/weekly/ pdf/prf1523 and 1524.pdf), from November 1 (heliolongitude E63) to November 6 (W08), the sunspot area in this region increased from 60 to 910 millionth parts of hemisphere (m.p.h.), the number of sunspots in this region increased from 6 to 33, and the magnetic configuration changed from simple () to flare-productive (). The number and area of sunspots began to decrease after November 6 and repeatedly increased to 48 on November 8 and to 730 m.p.h. on November 9, respectively. A rapid evolution of AR 10696 was accompanied by high sunspot activity: 13 M- and two X-class X-ray flares occurred when the active region crossed the disk (Fig. 1). High flare activity was combined with very high eruptive activity. During November 3­10, the SOHO/LASCO white light coronagraph registered many considerable coronal mass ejections (CMEs) including nine CMEs of a halo type with a emission around significant part or the entire occulting disk of the coronagraph. Figure 3 presents the difference images of these CMEs. For each event, these images were obtained using the LASCO/C3 coronagraph data by subtracting a background image before eruption from images at the phase of development of the corresponding CME. The CME shape in the plane of the pic2005


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Big Bear magnetogram

(c)

SOHO/EIT, 284 å

696

2004/11/05

1019 2004/11/05

1921 2004/11/05

1906

Fig. 2. Heliograms in the (a) H line and (c) 284 å UV channel for November 5, 2004. (b) The fields of the northern and southern polarities are light and dark, respectively. AR 10696--the main source of flare activity--is localized.

ture indicates that these ejections are large-scale and even global: the CME linear dimensions were several ten times as large as the visible disk diameter even at distances of 10­20R (solar radii) from the Sun. In this case the brightest CME structures shifted from the northeastern to the northern and then to the northwestern sectors of the near-Sun space as AR 10696 crossed the disk. Emission observed around other limb sectors indicates that the CME angular dimensions were considerable and the component of CME propagation in the direction perpendicular to the plane of the picture, in this case toward the Earth, could be substantial. The chronological development of the flare and eruptive events in the considered sunspot group was as follows: the first M1.6/1N flare event was registered near noon on November 3 (the emission maximum was observed at 1335 UT) and was accompanied by dynamic radio bursts of types II and IV and by a bright CME directed northeastward. A large M5.0/SN flare event occurred at 1535 UT and was accompanied by radio bursts of types II and IV and by a considerable asymmetric CME (appeared for the first time at 1606 UT according to the data of the C3 coronagraph on SOHO), which developed on the northeastern limb with a skyplane speed of about 900 km/s. An M1.0/SF flare, which occurred at 1803 UT and was also accompanied by an asymmetric CME of low intensity, was the last event of this day. A long-duration C6.3/SF flare event occurred 14 h later (at 0845 UT on November 4) and was accompanied by a significant radio burst of type IV and by a rather large partial halo CME (at 1042 UT) with the main ejection developed northeastward at a sky-plane speed of ~635 km s­1. A rather rare event occurred at the end of November 4: two M2.5 (at 2142 UT) and M5.4 (at 2253 UT) X-ray flares with radio bursts of types II and IV were observed during a 1N optical flare that continued for more than 2 h. The initial phase of this flare, corresponding to the first X-ray flare, occurred in the following part of the sunspot group. When the second X-ray flare began, the emission occupied the group center and one emission ribbon reached

the penumbra of the leading sunspot. This flare event generated a complicated partial halo CME (at 2342 UT) with propagation of two disturbance fronts [LASCO CME List 2004, ftp://lasco6.nascom.gov/pub/lasco/status/LASCO_CME_List 2004]. The first front developed mainly near the northeastern (NE) limb, whereas the second front occupied the western hemisphere (covered about 290° according to the C3 data). The mean skyplane speed of CME propagation was ~1050 km s­1. November 5 was a relatively quiet day since both M4.0/1F (1123 UT) and M1.2/SF (1910 UT) flares were not accompanied by CMEs. Flares and CME that occurred on November 3­5, when AR 10696 was located on the eastern hemisphere, did not result in considerable disturbances in the nearEarth space. Energetic particles, which were possibly accelerated during these events, apparently passed east and northeast of the Earth propagating along the helical IMF lines. Disturbances of the interplanetary medium and the magnetosphere caused by these solar events are considered in detail in the next sections of this paper (see Figs. 11, 12, Table 4). At the beginning of November 6, a rather rare flare event occurred in the active region located near the central meridian (N09 E05). A 2N optical flare "combined" three considerable X-ray flares: M9.3 (0011 UT) with dynamic radio bursts of types II and IV, M5.9 (0044 UT), and M1.4 (0140 UT). However, this activity (as well as the events of November 3­5) did not lead to an increase in the near-Earth flux of energetic protons. This flare event resulted in a complicated full halo CME with three clearly defined components started at 0131, 0206, and 0242 UT (according to the C3 data, Fig. 3). The mean speed of disturbance propagation in the sky-plane was about 960 km s­1. The strongest geomagnetic storm with a Dst minimum of about ­373 nT at 0700 UT on November 8 (Fig. 1) was preceded by three pulses of sudden commencement (SC) registered at 0257, 1052, and 1827 UT on November 7, respectively. This indicates that the corresponding interplanetary disturbance was complicated and the preceding
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(h)

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Fig. 3. Difference images of the largest "halo" CMEs registered by the SOHO/LASCO/C3 white light coronagraph on November 3­10, 2004. Dates and times of the main and background frames are shown at the bottom of each frame.

eruptive events that occurred on the Sun in the middle of November 4 (Fig. 3c), on the night of November 4­ 5 (Fig. 3d), and during November 5 (Fig. 2) possibly contributed to this disturbance (see Table 4). Finally, on November 7 the active region generated the X2.0/2B flare (1542 UT) which was the strongest event during the first period of flare energy release. This flare was accompanied by the most intense radio signal at all observed frequencies, dynamic radio bursts of types II and IV, and full halo CMEs. According to the C3 SOHO data, the bright and very wide loop front developed mainly to WNW and slightly moved southward forming full halo (see ftp://lasco6.nascom.gov/
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pub/lasco/status/LASCO_CME_List 2004). The ejection first appearance in C3 was registered at 1718 UT. The mean sky-plane speed of disturbance propagation was 1460 km/s. Since AR 10696 was located at that time on the western hemisphere (coordinates N09W17), this event was accompanied by a considerable increase in the near-Earth proton flux, the maximum of which at energies E > 10 MeV reached 4.6 â 102 cm­2 s­1 sr­1 (Fig. 11). SC registered at 0930 UT on November 9, which corresponds to an interplanetary shock estimated velocity of about 1000 km/s, is probably related to this event. The second eruptive event, which could contribute to the geomagnetic storm of
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06/11

1915

07/11

1515

08/11

1552

03/11

1603

06/11

1915

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Fig. 4. SPIRIT/CORONAS-F images of the Sun in the 175 and 304 å channels obtained on November 3­8, 2004.

November 10 with Dst ­289 nT, was observed at 0330 UT on November 8 as a less intense (SF/C7.9; coordinates N08W28) but more prolonged flare (Fig. 1) and a relatively faint diffuse and slow (V 430­ 520 km s­1) full halo CME (Fig. 3g). At 1543 UT on November 8, this active region generated the next M2.3/1N flare with a very feeble CME registered at 1730 UT. The second period of flare activity, which was maintained by the new outflow in driven and central parts of the sunspot group on November 6­7, began on November 9. Two large flares (2N/M8.9 flare, coordinates N07W51, at 1719 UT on November 9 and 3N/X2.5 flare, coordinates N09W49, at 0213 UT on November 10) and two CMEs (full halo CME at 1748 UT on November 9 with a sky-plane speed of 1800 km s­1 and "asymmetric full halo" CME at 0242 UT on November 10 with a mean sky-plane speed

of disturbance propagation of about 2000 km s­1) occurred in the active region over 9 h when a bright emission was observed over the entire western limb (Figs. 1, 3h, 3i). Since the sources were localized in the western disk sector, these events did not result in substantial geomagnetic disturbances but were accompanied by one more growth of the proton flux with a peak intensity of (3­4) â 102 cm-2 s­1 sr­1 (Fig. 11). We should also state that the magnetic polarity distribution in AR 10696 was a substantial factor responsible for the intensity of the geomagnetic storms of November 8 and 10. The magnetogram in Fig. 2b indicates that positive and negative polarities dominated in the northern and southern zones of the region, respectively. If we assume, following Pudovkin et al. [1977], that during eruption the magnetic field is somehow carried by an interplanetary disturbance and the field polarity remains unchanged in the source, the above

Table 2. Flares and CMEs registered by the SPIRIT telescope on November 1­9, 2004 Date Nov. 3, 2004 Nov. 6, 2004 Nov. 7, 2004 Nov. 8, 2004 Flare class M5.0 M3.6 X2.0 M2.3 Flare beginningCME beginning AR no. max-end (GOES) (UT)* 1535-1547-1555 0140-0157-0208 1542-1606-1615 1543-1549-1552 696 696 696 696 1606 0131 1554 1554(?) 1430 1630 Direction* 342 036 120 313 325 CME V, km s­1 angle width* (linear approx.)* 316(H) 196 20 26 10 781 612 1953 558 220

* LASCO/SOHO data processed using the CACTUS program developed at Belgian Royal Observatory (see http://sidc.oma.be/cactus/out/latestCMEs.html). GEOMAGNETISM AND AERONOMY Vol. 45 No. 6 2005


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2124­1512

0693 0696 0695

08/11­04

1552­0942

08/11­04

1552­0942

08/11­04

1600­0936

Fig. 5. Fixed difference images in the 175 and 304 å channels of the SPIRIT telescope and similar images in the 195 å channel of the SOHO/EIT telescope obtained on November 3, 6, 7, and 8, 2004. The times of registration of the current and base images are shown in the lower right-hand corner.

polarity distribution on the Sun had to result in a substantial negative Bz component near the Earth, precisely which was observed during the geomagnetic storms of November 8 and 10 (see subsection 3.1, Fig. 12).
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The described eruptive events (specifically, large CME of November 6­10 and corresponding interplanetary disturbances) resulted also in a complicated, deep, and prolonged Forbush decrease in the GCR
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Ni XVII Al X

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300

310

320

330 Wave length, å

Fig. 6. (a) Spectrogram of the Sun in the 285­335 å spectral region obtained during the flare of November 8, 2004 (1549:28 UT); (b) dispersion directions and scans on the solar disk; and (c) spectra along scans 1 (flare region) and 2 (dimming region and quiet areas).

intensity. This decrease started on November 7 simultaneously with the first geomagnetic storm and reached the maximal amplitude on November 10, and the recovery phase of this event lasted up to the middle of November (for details see subsection 3.4, Table 5). 2.2. Solar Activity Dynamics according to CORONAS-F/SPIRIT Data The SPIRIT telescope on the CORONAS-F satellite was used in the observations performed on November 1­8, 2004 [Oraevskii et al., 2002]. In this case the full disk images in the channels 175 and 304 å were registered four times a day at intervals of 4­8 h and complete spectrograms were registered two times a day. Several

obtained telescopic images are shown in Fig. 4. Table 2 presents the times of flares and CMEs occurred during this period, for which SPIRIT data are available. 2.2.1. Dimmings. Fixed difference images, which reflect total activity changes between two successive frames, were constructed in order to study the structures of dimmings (local variations in the emission intensity on the solar disk). Images corresponding to instants before flares were selected as reference pictures. The next images in both channels were turned against solar rotation to the time of base frames, and base images were subsequently subtracted from these images. Brightness in difference images was reduced to the nonlinear scale in order to make dimmings more contrasting.
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689

July 6, 2004

July 8, 2004

July 9, 2004

July 10, 2004

July 11, 2004

Fig. 7. SOHO MDI solar disk magnetograms. The magnetic structure of AR 10696 monotonically varies during the entire period.

Fixed difference images obtained using the SPIRIT telescope and similar SOHO/EIT images are compared in Fig. 5. All events listed in Table 2 occurred in a large complex which combines ARs 10693, 10695, and 10696. A classical pair of compact dimmings, corresponding to footpoints of an eruptive magnetic loop, was generated as a result of the flare and eruptive event occurred on November 3 near AR 10696. These dimmings are very contrasting in the channels 175 and 195 å and are much less distinct in the channel 304 å, which can be caused by the delay in the dimming development in the transition layer [Chertok et al., 2004]. Several dimmings were registered on November 6. A contrasting compact dimming east of AR 10696 and a narrow northwestward dimming were observed in all channels. An extensive southwestward dimming toward AR 10695 was also observed in the coronal channels 175 and 195 å. This dimming is not observed in the transition layer channel 304 å and possibly replaced a high transequatorial loop with a temperature of about 1­2 MK that existed previously and is invisible in the channel 304 å. Eruptive events of November 7 resulted in the generation of several large-scale dimmings near ARs 10696, 10695, and 10693, which indicates that the magnetic structures of these regions are closely interrelated. In addition to compact dimmings near ARs 10696, 10695, and 10693, a diffuse extensive dimming was formed north of AR 10696 in place of brightening previously observed in the initial images at the boundary of a low-latitude coronal hole. On November 8, the dimming pattern was generally the same as on the preceding day; however, an extenGEOMAGNETISM AND AERONOMY Vol. 45 No. 6

sive dimming similar to a dimming of November 6 appeared in coronal lines between ARs 10696 and 10695 in addition to compact dimmings near all three ARs. This indicates that a transequatorial loop of the scale R/2 ~ 300 000 km recovered during two days. In addition to dimmings, the difference images also indicate that brightness recovered in the region of a diffuse dimming to the north of AR 10696 and a high arc system appeared near AR 10693 stretching outside the limb; however, the relation of these events to flares and CMEs that occurred during this period is not evident. Chertok [2005] analyzed in detail large-scale solar activity related to the considered series of flares and CMEs using the SOHO/EIT UV telescope data
Table 3. Ion spectral lines observed during the flare of November 8, 2003 Ion He II Si VIII Mg VIII Al X Si IX Si XI Fe XV Ni XVIII Fe XVII Ca XVIII
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Wavelength, å 303.78 314.36, 316.22, 319.84 313.74, 315.02, 317.03 332.79 292.81, 296.16 303.33 284.16 291.98 323.47 302.19

log10(T 4.9 5.9 6.0 6.1 6.1 6.2 6.4 6.7 6.9 7.0

max)


690 0.5 0.4 0.3 0.2 0.1 0 1.6 1.2 0.8 0.4 0 ­ 0.4 1.6 1.2 0.8 0.4 0 3.5 2.5 1.5 0.5 4 3 2 1 0 4 3 2 1 0

YERMOLAEV et al. Polarized flux AR 10696
Nov. 2, 2004 8h57m UT A0 10696

3.5 2.5 1.5 0.5 2.5 2.0 1.5 1.0 0.5 0 1.6 1.2 0.8 0.4 0 0.6 0.4 0.2 0 ­ 0.2 0.3 0.2 0.1 0 ­ 0.1 ­ 0.2 0.10 0.05 0 ­ 0.05 0

Nov. 8, 2004 8h57m UT A0 10696

7

9

11

13

15
Nov. 3, 2004 8h57m UT A0 10696

17

Nov. 9, 2004 8h57m UT A0 10696

7

9

11

13

15
Nov. 4, 2004 7h59m UT A0 10696

17

Nov. 10, 2004 8h57m UT A0 10696

7

9

11

13

15
Nov. 5, 2004 8h57m UT A0 10696

17

Nov. 11, 2004 8h57m UT A0 10696

Nov. 6, 2004 9h55m UT A0 10696

Nov. 12, 2004 7h58m UT A0 10696

Nov. 7, 2004 9h55m UT A0 10696

Nov. 13, 2004 9h56m UT A0 10696

5

7

9

11

13 15 17 Frequency, GHz

5

7

9

11

13 15 17 Frequency, GHz

Fig. 8. The dynamics of the total polarized emission flux spectrum of AR 10696 from November 2 to November 11 according to the RATAN-600 data. The spectrum growth at high frequencies (11­16 GHz) is pronounced on November 4­7 (shown by the upward arrow). The emission flux sharply decreases on November 8 and 9 (downward arrow) due to the effect of darkening (see also Fig. 10).

(see also different heliograms and movies at the Web site http://helios.izmiran.troitsk.ru/lars/Chertok/04_11/ index.html). 2.2.2. November 8, 2004, flare spectrum in the band 285­335 å. Figure 6 demonstrates the SPIRIT spectrogram of the Sun in the 285­335 å spectral region obtained at 1549:28 UT at an exposure of 150 s, i.e., almost at X-ray flare maximum according to the GOES data. In individual spectral lines, the Sun images have the shape of ellipsoids oblate in the dispersion direction