[20] Zhou and Zheng [1998] analyzed 11 ARs observed during the 5-year period from March 1989 to February 1994 characterized by powerful proton events. Zhou and Zheng [1998] emphasized that almost all AR had a spot morphology of the d type, when several umbrae of the opposite magnetic polarity were submerged into the joint semi-shadow. For the majority of ARs the total area of the spots was more than 1000 m h (millionth of the hemisphere), the ARs covered more than 10 degrees in heliographic coordinates on the solar disc, and their magnetic configuration was of the bgd type. Usually such AR are characterized by an unbalance of the magnetic flux. The flux of the leading polarity may be up to 80 and more percents (AO NOAA 5395, 5629, 6555, 6659). Therefore the magnetic field lines connected to the most part of the AR area are closing outside the boundaries of AR sometimes at large distances in other active complexes or at elements of the enhanced chromospheric net.
[21] In all AR a strong magnetic field (2500-3000 G) as comparable to MF within the umbra is observed [Makarova et al., 2001]. Parallel to the MF neutral line, there exists a narrow corridor with high (0.3-0.5 G km -1 ) gradients of the strength of the longitudinal magnetic field [Sakurai et al., 1992] and strong (up to 4000 G) transverse magnetic fields detected in polarization observations of spectral lines [Tanaka, 1991; Zirin and Wang, 1993]. The spot motions with high velocities of dozens of m s-1 up to a few hundred m s-1 and motions in the penumbra along the neutral line of MF were observed [Tang and Wang, 1993; Wang et al., 1991; Zhang et al., 1994].
[22] In the AR McMath 13043 which presents a large spot having formed as a result of a fusion of two multipoles, a velocity up to 800 m s -1 was observed. Liu and Zhang [2001] analyzed the relation between the large-scale motions of sunspots and the strong flare on 14 July 2000 (3B/X5.7) in AR 9077. They found that a specific configuration of MF and rapid fragmentation led to a well-pronounced shear structure. The spot motion induced activation of part of the filament. The emergence magnetic flux initiated the flare on 14 July at the stage of the beginning of AR destruction.
[23] The magnetic field in the considered AR has a pronounced shear character in the penumbra. This fact is seen in the images obtained with a high spatial resolution in the Ha and HeI D3 lines and is confirmed by the measurements of the transverse magnetic field. One can see that the filaments are parallel or almost parallel to the neutral line of MF. For example, in the AR 5395 on 11 March the mean shear angle along the eastern boundary of the inversion line of MF was 61o [Chen et al., 1994]. In the penumbra the magnetic field lines are often twisted into a helix [Zhang, 1995b; Zhang et al., 1994]. Though the shear character of MF in the flare productive AR is well known; however, still it is not clear why the changes occurring in the topology of MF during a flare are ambiguous. Observations show that as a result of a flare the degree of the shear may decrease, stay unchanged, or increase [Spirock et al., 2002; Zhang, 1995a]. Constancy or intensification of the magnetic shear after a flare probably is explained by the fact that the flares were induced by interaction of new emerging fluxes into the already existing magnetic field and the flares did not result in a sufficient relaxation of MF.
[24] Zhou and Zheng [1998] analyzed the ARs rotation during their motion over the solar disk. To study the rotation of a group of sunspots in an AR a characteristic line is chosen. For example, in the AR 5395 the line was chosen connecting the centers of the two largest sunspots. Every day the angle between this line and the east-west direction was measured. The projection effect was taken into account. It was found that at the moments when the rotation velocity (calculated in the degrees per day) reaches its maximum value a strong proton flare can occur. Then the rotation velocity begins to decrease and the group starts rotating into the opposite direction. One can suggest that when the turning angle reaches some critical value, the twisting of the magnetic field lines increases, a reconnection occurs, and the magnetic energy is released in the form of a proton flare. The forces of elasticity and magnetic line tension make the group to rotate in the opposite direction after the flare has occurred.
[25] There are observational data indicating that the character of disturbance propagation in the interplanetary space depends on the solar activity cycle. For example, the observations on board the Ulysses spacecraft showed that strong disturbances during the maximum of solar activity in June 1991 were apparently related to six flares of the (1F-4B)/(X10-X12) classes in the AR NOAA 6659 (a heliographic latitude of the AR was N34). One of the flares occurred behind the limb. The character of propagation of these interplanetary disturbances was in a highest degree anisotropic. The majority of the disturbances were observed in the northern hemisphere of the interplanetary space. Therefore one can conclude that the source of the interplanetary disturbance was located within or around the active region where a series of powerful flares occurred. Observations during the rising branch of the solar activity cycle in November 1997 demonstrated a different character of interplanetary disturbances: they were approximately symmetric in the southern and northern hemispheres relative the heliospheric current sheet, though a flare of the X9 class was also observed [Watanabe et al., 2000].
[26] The entire set of the observational data currently can not be explained by any model of a solar flare. Shea and Smart [1990] indicated that the idea that energetic particles are always related to strong solar flares contradicts to observations. Cases are known when proton flux was related to the disappearance of a filament without an accompanying flare [Kahler et al., 1986]. Though AR are large d islands and most often are a source of energetic protons, this can not be considered as a regularity. For example, no flare accompanied by proton fluxes was detected within the AR 7070, which was a large d configuration. On the other hand, studies of the line intensities in the 1200-1800 Å range during the impulsive phase of the 3B/X3 flare on 27 February 1992 (NOAA 7070) showed an increase of the solar emission in the C IV and Si IV lines by a factor of 12-13. This corresponds to the increase of the intensity of the flaring plasma by a factor of 15,000. The increase of the emission of the Lya line (by ~6%) agrees with the current model of the flares at the decaying phase. However, the cause of such increase in the intensity of the C IV and Si IV lines is not yet clear, though there is an agreement with the observations conducted for stars [Brekke et al., 1996].
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