The non-thermal electrons accelerated during solar flares can produce enhanced and broadened chromospheric lines when they precipitate into the chromosphere. In this paper, we propose a method to diagnose the non-thermal processes using two chromospheric lines, ${H\alpha}$ and Ca ${\sc ii} 8542 \AA}$ lines. First, we perform non-LTE calculations of these two lines for various (thermal) model atmospheres and (non-thermal) electron beams. Since the two lines have different sensitivities to the non-thermal electrons, a set of line spectra can uniquely determine a model atmosphere and an electron beam. We then apply this method to a solar flare for which we have observed two-dimensional spectra of the two lines. In particular, we examine the temporal variation of thermal vs. non-thermal effects in flare bright kernels, as well as the spatial variation across flare ribbons. The results show clearly that the non-thermal effects appear most obviously at the flare maximum, and preferentially at the outer edges of flare ribbons. The results are consistent with flare theoretical models.

We extrapolated observed photospheric magnetic field before the 3B/X1.2 flare occurred in NOAA 10486 on 2003 October 26. Two magnetic null points exist above the active region, which have no crucial role in triggering the flare, even though enhanced TRACE EUV/UV emission was observed before the main flare due to magnetic reconnection near the lower-altitude null point. We conclude that this flare results from the loss of equilibrium due to persistent flux emergence and photospheric motion, and strong shear. The accompanying fast CME with velocity of $\sim$ 800 km $s^{-1}$ shows quick mass pickup and energy increase in the low corona. Its kinetic energy is always larger than its potential energy.

We study variations of solar activity (sunspot numbers W) and anomaly of global temperature (GT) to detect a connection of their time variations on different time scales (including trends) to understand cause of global warming. We use a method of non-linear spectral analysis that is capable of making a self-consistent selection of trends, non-stationary oscillations and identifiing time intervals of development of non-linear processes (appearence of oscillations of large amplitude) in data. Analysis shows that trends of both spectra contribute main part to the data changes and show correlated increasing of W and GT during the studied interval. Cause of Maunder Minimum and present global warming is regime change (from epoch of damping to epoch of building up) of the powerfull oscillations at T = 1000 yr. from the GT spectrum. Besides, time changes of GT and W has different type of connection in different range of periods T: non-stationary oscillations from the spectra of W and GT at T = 10 yr. and T = 30 yr. vary in opposite phase, at T = 22 yr. vary in phase. The latter means different influence of odd and even 11-yr solar cycles on anomaly of GT (warming and cooling accordingly).

Magnetic field topology at the CME source regions is considered to play a role in CME initiation processes. We use observational data and Potential Field Source Surface model to investigate the magnetic field topology over CME productive quiescent filaments. We found both bipolar topology and quadrupolar topology at CME source regions, but bipolar topology is more common overall and in each year. The total occurrence ratio between bipolar and quadrupolar topology is about 3:1 with our 80 events. On the rising phase of the solar cycle, there is mostly bipolar topology, but on the declining phase, there is a mixture of both bipolar and quadrupolar topology.

A clear case on Dec. 28 2002 is presented. It is about the initiation of two successive CMEs, which were related to an eruptive prominence. In EIT 304 Å and 195 Å observations, we found a long filament severely twisting in a piece of its fragments, which appeared as a prominence on Dec. 26. Then, the prominence converted its twist into writhe. Two days later, the prominence displayed a slow rising motion for hours. There happened internal twisting and mass motion before the prominence rapid acceleration and final eruption. Two successive CMEs recorded by LASCO C2 coronagraph corresponded to the early rising and the subsequently eruptive phases of the prominence, respectively. Evidence of magnetic reconnection, i.e., a cusp structure and post-flare loops in EUV wavebands, and hard X-ray sources in the corona, were observed after the prominence disruption. It appears that the kink instability and the mass drainage in the prominence played important roles in triggering two CMEs' initiation. We suspected that the rather impulsive acceleration of the second CME resulted from magnetic reconnection beneath the prominence.

We present results of our study of dependence of planetary geomagnetic activity from geometric factors in geoeffective parameters taking into account orientation of the geomagnetic moment M relative to the vectors of the Interplanetary Magnetic Field (IMF) and electric field of the solar wind E during annual and daily motions of the Earth. We take as our data base space measurements of the IMF and solar wind velocity at the Earth's orbit for 1964-1998 and Kp, Dst indices. Variations of the geometric factors determined by mutual orientation of the vectors E and M can explain 50% of observed variations of Kp and 75% of Dst. We show that geomagnetic activity can reach very high levels of geomagnetic activity Kp = 8 for invariable values of the solar wind electric field by changing only geometric factors.

We present a statistical investigation of shear motion of the EUV footpoints in two-ribbon solar flares, using the high spatial resolution data obtained in 1998–2005 by the Transition Region and Coronal Explorer (TRACE). In this study we have selected 50 well-observed X- and M- class two-ribbon flares. Our preliminary results are: a) 86% (43 out of 50) of these flares show shear change of footpoints and ribbon separation; b) there is no obvious ribbon separation in those 7 flares which have no shear change of the conjugate footpoints; c) in most events, the cessation of shear change is 0–2 minutes earlier than the end of the impulsive phase.

Using the data from BBSO, YNAO and SOHO/MDI we studied the formation and evolution of a ring-filament which was located in NOAA AR09470 from May 21 to 24, 2001. We found that: (1) the ring-filament's formation was well associated with newly-emerging flux. (2) all the eruptions of the filament happened during the decay of the emerging bipoles.

A suggested method is proposed to forecast the general features of the 11- year solar activity principle cycle. It is based upon the count of lengths and durations of spotless events, prevailing in the preceding minimum of the coming new cycle. The method has been successfully applied to predict the strengths and time of rises for the $22^{nd}$ and $23^{rd}$ 11-year cycles. The proposed precursor technique is further developed to make preliminary prediction of the maximum relative sunspot number and the time of rise of the $24^{th}$ 11-year cycle. The predicted values of these parameters are found to be $90.7\pm9.2$ and $4.6 \pm1.2$ year respectively. In addition, neural, Fuzzy neural and genetic algorithms have been also applied for the confirmation of the predicted results. A comparison with the early predictions used by other methods is given.

Based on the neutron monitor counting rate profiles, soft X-ray emission from GOES, Yohkoh/HXT, RHESSI/HXT, ACE/SIS, and SOHO/LASCO CME catalog, the relationship between the onset time of solar cycle 23 Ground Level Enhancements(GLEs) and solar activity are analyzed. It was found that the correlation between the onset time of GLEs and flare maximum is better than that of the onset time of metric type II radio burst and CME. Average value of the ratio of Fe/O is about 2.65 times of coronal value in the range 30 – 40 MeV/n for all events. If considering the parent flare sites, the situation of proton acceleration in flares, and transport effect from flare sites (if it located in poorly-connected region) to well-connected region, several GLEs onset time are roughly at the peak time of the X-ray.

The study of the differential rotation law is an important issue in solar physics. Earlier studies of filaments found formulae for their differential rotation at stable existence stage. This paper relies on Big Bear Solar Observatory H-alpha filtergrams to estimate angular velocities of quiescent filaments at different stages of existence. Angular velocities are shown to cover a wide range of values. Likely causes of this velocity scatter are discussed.

We analyze the periodicities for 294 solar flares observed by Nobeyama Radioheliograph over 6 discrete frequencies of 1, 2, 3.75, 9.4, 17 and 35 GHz during the solar cycle 23 between 1998 and 2004. Using Fourier analysis, we pick up the shortest period ($T_{\rm{s}}$) for each event at each frequency channel. We find that $T_{\rm{s}}$ varies in the range of 0.25–0.62 s over 6 frequency channels.

Based on the concept that the CMEs are the results of coronal magnetic restructuring or reconfiguring, we analyze the December 18, 2000 event by using Nançay Radioheliograph (NRH) images and combining the multi-spatial scale observations. We investigated the onset, duration and position of the radio emissions in relation to EUV dimming and the inferred CME onset, with the purpose to estimate the spatial and temporal scales of the coronal restructuring, thus, to understand the physics of the initiation and development of the CME.

The solar magnetism, its origin, and its impact on the earth are of primary interest for solar physicists. The understanding of the solar dynamo in the convection zone and the coupling of the magnetic fields up to the corona and the heliosphere calls for synoptic as well as for high spatial resolution observations of the Sun. Understanding the interactions between radiative and magneto-convective processes at the interface between the solar interior and the atmosphere requires spectro-polarimetric observations at high spatial and spectral resolution with high polarimetric accuracy. Thus large-aperture telescopes are needed to resolve the small scales and to collect enough photons to study the evolution of the magnetic processes. For assembling the mosaic of the solar dynamo and its magnetic coupling out to the heliosphere, large scale properties and hence synoptic observations play a crucial role. I present my personal perspective of the prospects in ground-based solar physics, and comment on the planned and upcoming new facilities including SOLIS, GREGOR, NST, SUNRISE, and ATST, as well as ALMA and FASR, but also mention the upcoming space missions HMI@SDO and SOLAR-B.

SOLARNET is a medium size high resolution solar physics mission proposed to CNES and ESA for a new start in 2007 and a possible launch in 2012 (CNES) or later (ESA Cosmic Vision framework: 2015–2016). Partnerships with India and China are under discussion, and several European contributions are considered. At the center of the SOLARNET mission is a 3-telescope interferometer of 1 meter baseline capable to provide 40 times the best ever spatial resolution achieved in Space with previous, current or even planned solar missions: 20 mas - 20 km on the Sun in the FUV. The interferometer is associated to an on-axis Subtractive Double Monochromator coupled to an Imaging Fourier Transform Spectrometer capable of high spectral (0.01 nm) and high temporal resolutions (50 ms) on a field of view of 40 arcsec and covering the FUV and UV spectral domains (from 117.5 to 400 nm). This will allow to access process scales of magnetic reconnection, dissipation, emerging flux and much more, from the chromosphere to the low corona with emphasis on the transition zone where the magnetic confinement is expected to be maximum. A whole new chapter of the physics of solar magnetic field structuring, evolution and mapping from the photosphere to the high atmosphere will be opened. The interferometer is completed by instruments providing larger field of view and higher temperature (EUV-XUV coronal imaging & spectroscopy) to define the context and extension of the solar phenomena. The 3-telescope interferometer design results of an extensive laboratory demonstration program of interferometric imaging of extended objects. We will review the scientific program of SOLARNET, describe the interferometer concept and design, present the results of the breadboard and give a short overview of the mission aspects. In a different category, LAIME, the Lyman Alpha Imaging-Monitor Experiment, is a remarkably simple (no mechanisms) and compact full Sun imager to be flown with TESIS on the CORONAS-PHOTON mission in 2008. It could be the only chromospheric imager to be flown in the next years, supporting Solar-B, STEREO, SDO and the Belgian LYRA Lyman Alpha flux monitor. We will give a short description of this unique 60 mm aperture imaging telescope, dedicated to the investigation of the UV sources of solar variability and of the chromospheric and coronal disruptive events (Moreton waves, prominences, CMEs, etc.).

The Prototype Brazilian Decimetre Array (PBDA) consists of 5 element alt-azimuth mounted parabolic dishes of 4-m diameter, having baselines up to 216 m in East-West direction. We present initial solar observations carried out with the PBDA during the period 22$^{\hbox{\scriptsize{nd}}}$ November to 11$^{\hbox{\scriptsize{th}}}$ December, 2004. The frequency of observation was 1.6 GHz. The temporal and spatial resolution were 100 ms and 3 arcmin, respectively.

Spectropolarimetric methods used at the Sayan Solar Observatory for measuring magnetic field strengths are described. The spectropolarimeter consists of a polarization splitter and a ferroelectric liquid crystal (FLC) modulator, allowing for several longitudinal H measurement modes. The report discusses advantages and disadvantages of modulation-based and modulationless measurements using ordinary slow CCD cameras. In some cases combined variants appear to be preferable.

We present a brief description of new complex of space telescopes and spectrographs, TESIS, which will be placed aboard the CORONAS-PHOTON satellite. The complex is intended for high-resolution imaging observation of full Sun in the coronal spectral lines and in the spectral lines of the solar transition region. TESIS will be launched at the end of 2007 – early of 2008. About 25 % of the daily TESIS images will be free for use and for downloading from the TESIS data center that is planned to open 2 months before the TESIS launching at http://www.tesis.lebedev.ru

Observations of source regions of coronal mass ejections have progressed enormously in the past decade with the observations from SOHO and Yohkoh. Progress has been made on understanding magnetic helicity, coronal dimming, coronal waves and flares in terms of their relationship to CMEs. Observations have been used to verify and disagree with models such as tether-cutting, kink instabilities and the breakout model. We will describe the observations, recent models, and how future observations from the Solar-B and STEREO missions will address many unanswered questions.

Wave and oscillatory activity of the solar corona is confidently observed with modern imaging and spectral instruments in the visible light, EUV, X-ray and radio bands, and interpreted in terms of magnetohydrodynamic (MHD) wave theory. The review reflects the current trends in the observational study of coronal waves and oscillations, theoretical modelling of interaction of MHD waves with plasma structures, and implementation of the theoretical results for the mode identification. Also the use of MHD waves for remote diagnostics of coronal plasma - MHD coronal seismology – is discussed.