We report a detailed examination about the relationship between the evolution of the H$\alpha$ flare ribbons and the released magnetic energy during an X2.3 solar flare which occurred on 2001 April 10. We successfully evaluated the released energy quantitatively, based on the magnetic reconnection model. We measured the photospheric magnetic field strengths and the separation speeds of the fronts of the H$\alpha$ flare ribbon, and estimated the released magnetic energy at the flare by using those values. Then, we compared the estimated energy release rates with the nonthermal behaviors observed in hard X-rays and microwaves. We also estimated the magnetic energy released during the flare. The estimated energy release rates in the H$\alpha$ kernels associated with the hard X-ray sources are locally large enough to explain the difference between the spatial distribution of the H$\alpha$ kernels and the hard X-ray sources. Furthermore, we reconstructed the peaks in the nonthermal emission by using the estimated energy release rates.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

RESIK is the bent crystal spectrometer aboard the CORONAS-F satellite. It is equipped with four PIN diode detectors. These detectors were used in order to detect background counts due to energetic particle contamination present within polar regions and SAA belts. At altitudes above 300 km (Coronas-F altitude is about 500 km) the population of charged particles trapped by the Earth's magnetic field consists of protons (energies between 100 keV and several hundred MeV) and electrons (energies between few tens of keV and 10 MeV). The construction of RESIK PIN diode detectors allows to sense particles with the energy above 1 MeV. We present diagrams illustrating the coupling of the Coronas-F particle environment and selected proxies of solar activity. The data shown have been collected during initial phase of mission.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The longitudinal distribution of sunspot activity for 1917-1995 is studied using vector sums of sunspot areas. It is shown that the sunspot distributions behave differently during the Ascending phase and Maximum (AM) of the solar cycle on one hand and for the Declining phase and Minimum (DM) on the other depicting maxima around roughly opposite longitudes. While the maximum of the distribution for the AM period is found around the Carrington longitude of 180$^\circ$, the maximum for the DM period is at the longitude of about 0$^\circ$.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We review the small number of known observations of planetary transits made in Ireland in the 18th century with particular reference to the 1769 observations of Venus by Charles Mason. Though inconclusive, there is evidence to suggest that planetary transits were instrumental in the foundation of at least one of the principal observatories in Ireland. In addition, we note the close personal involvement and the contributions of Nevil Maskelyne, the prime mover of the UK 1769 Transit observations, in the design and equipment of these observatories.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Preliminary analysis of spectra collected with the RESIK Bragg bent crystal X-ray spectrometer aboard CORONAS-F indicates the presence of many spectral features which until recently were unidentified. We present RESIK spectra in which the H-like Cl XVII Ly$\alpha$ line at 4.182 Å and He-like Cl XVI triplet components in the range 4.43 Å-4.45 Å are identified.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We examined two “magnetic antibuoyancy” effects: i) turbulent diamagnetism and ii) magnetic advection caused by vertical inhomogeneity of plasma density in the SCZ (the $\nabla \rho$ effect). The Sun's rotation which yields the $\nabla \rho$ effect with new properties was taken into account. It is shown that at high latitudes antibuoyancy effects block the magnetic fields in the deep layers of the SCZ. However, in the region located near-equator the $\nabla \rho$ effect, modified by rotation, causes the upward magnetic advection. So it can facilitate penetration of strong magnetic fields to solar surface where they then arise in the “royal zone” as the sunspots.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Changes in Total Solar Irradiance (TSI) were studied both in time-frequency and in time-longitude aspects. The continuous wavelet analysis of TSI composite time series (Fröhlich & Lean 1998; Willson & Mordvinov 2003) revealed that the energy of thermomagnetic disturbances due to sunspots and faculae cascades into the magnetic network and facular macrostructure. The time-longitude analysis revealed large-scale patterns of radiative excesses in solar atmosphere. These patterns are organized into 2- and 4- sector structures exhibiting the effects of both activity complexes and magnetically active longitudes. Large-scale patterns with radiative excess display a facular macrostructure. These temperature patterns are causally related to long lived magnetic fields of the Sun. During activity cycles 21–23 the patterns with radiative excess tend to be concentrated around the active longitudes which are centered at about 60° and 230° in the Carrington system (Benevolenskaya et al. 1999; Mordvinov & Willson 2003).To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We provide a brief overview of properties of transequatorial loops (TLs) and show that some TLs fit the description of a loop, while others appear to be the magnetic separators.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Explosive events and blinkers are two observational classes of transients seen on the quiet Sun and an investigation of the significance of and relationship between such events may be critical for understanding basic processes at work in the solar atmosphere. Our analysis showed that blinkers and explosive events are independent phenomena which have to be explained separately.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We report the “5+1” dynamical classification of the most frequently observed topologies of the magnetic field in sunspot groups associated with powerful flares (see Fig.1). The classification is based on the analysis of magnetographic and H$\alpha$ observations of more than 600 active regions on the span of 23 years (for detailed description see Ikhsanov 1982, Ikhsanov 1985).To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Sub-second time structure of hard X-rays observed during solar flares by spectrometer “IRIS” on a board of CORONAS satellite are discussed. The burst duration of 80ms and FWHM about 30ms are recorded in powerful flare of August 20, 2002 year at 0828:16.77 UT. A confidence level of this peak is 6$\sigma$.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The $\bf {E \times B}$ drift allows plasma to move through the magnetic field lines and may contribute to various motions inside the Sun (e.g. to explain the adverse gradient of differential rotation in the equatorial zone), at its surface and in the corona. Here we treat an example: using a given azimuthal angular frequency $\omega$(r, $\theta$), rather arbitrary, and the corresponding exact solution for $\bf{B}$, we obtain $\bf{E}$ and the drift velocity. The latter is comparable with the original velocity, but has components in all directionsTo search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Height series of Doppler observation in $H_{\alpha}$ and $D_3$ spectral lines of solar spicules obtained by big coronagraph (53 cm) of Abastumani Astrophysical Observatory have been analyzed. Time duration of each height series was 7 s. Totally 8 different heights from the photosphere were covered. Spatial difference between neighboring heights was 1 arc sec. We found the periodic spatial distribution of Doppler velocities during height series in certain spicules. We suggest that the periodic spatial distributions are caused by propagating or standing kink waves. The wave length is found to be in the range 3500–4000 km which probably indicates to the granular origin of the waves.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Comparison of solar magnetic fields observed with various telescopes and/or in different spectral lines is important to verify the data reliability from instrumental points of view, and to determine some physical processes responsible for the origin of polarized emission in the solar atmosphere with extremely complicated distribution of magnetic and thermodynamic parameters in an aperture of observation and along the line-of-sight. When compared observations use the same line, and data reveal a significant systematic discrepancies, the question arises about the reasons of that. If compared data are obtained in different spectral lines, the existence of differences between them could be related to peculiarities of the polarized emission formation in one or another line. In this case the question arises - data in which line are more reliable? This problem is especially acute with regard to observations in the FeI $\lambda$525.02 nm spectral line due to the big Lande factor ($g = 3.0$) and low excitational potentional of this line. Recently this problem has become especially urgent for some space weather tasks. Both the analysis of this problem and main bibliographic references can be found in [1].To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Based on analyzing the fine structure of time series of solar and heliospheric parameters a universal numerical technique is developed to study large-scale patterns of solar activity and the heliospheric structure. The Solar Mean Magnetic Field (SMMF) time series and the magnetic fields in solar corona (Hoeksema & Scherrer 2004) were studied in time-longitude aspect (figures 1a,b,c,d). It is shown that the behavior of the large-scale magnetic field, its multiperiodic rotation determine the heliospheric structure and changes in space weather (Mordvinov & Plyusnina 2004). Time-longitude analysis of Interplanetary Magnetic Field (IMF) near the Earth (King et al. 2004) reveals similar diagram (figure 1e) shifted relative to the photospheric and coronal magnetic fields by the transport time.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Analysis Wavelet-spectra has shown that in the with earlier our works, in a field of brightness of thin structure of photosphere scales of formations of granules, protogranules, and mezogranules come to light.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The possible mechanism of cosmic ray influence on clouds formation in the atmosphere is considered. Ionization of the atmosphere caused by cosmic rays can lead to the formation of condensation centers. But at the same time interaction between cosmic ray and the atmosphere might change transparency of the atmosphere and the atmospheric temperature, too. Calculations of changes of the condensation growth rate of water drops due to changes of the temperature have been performed. This effect can provide an increase in a few percents of growth rate of drops. This can explain the observed correlation between cloudiness and cosmic ray intensity.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Available YOHKON, TRACE, SOHO/EIT and CORONAS-F data are interpreted as evidences of the non-local coronal mass ejection initiation processes when rapidly increasing electric currents appear in the coronal loops and arcades. These electric currents are driven by subphotospheric processes. Self-similar plasma motions are due to the electric drifts in crossed inductive electric and magnetic fields. Expanding non-planar loops often mimic “reconnection” features, being in reality projection effects of the “twist and fold” processes on the image plane. Among such patterns one can find examples of spurious x-points, concave fronts, blobs, islands, etc. Coronal mass ejections often proceed without large scale topological changes of magnetic fields. They are accompanied by enhanced small-scale turbulence.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We model hot collisionless solar corona/slow solar wind (SW) by kinetic Vlasov equation. The equatorial region with an unprescribed magnetic field is under electromagnetic action, and we have formation of a 3D Quasi-Stationary Coronal Structures (QSCS) in the current-carrying (CC) plasma with SW flows. The QSCS are generated via electromagnetic mode development in plasma having anisotropic velocity distribution function (VDF). As a result we get streamers like stratification mode, CMEs like tearing mode and heliospheric sheet like pinch mode in anisotropic plasma. The scales in the QSCS are defined via angle dependent magnetic Debye scale. The scale itself depends on value and sign of plasma anisotropy parameter which is calculated for postulated plasma VDF.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The results of complex investigations of solar and interplanetary large-scale magnetic fields (LSMS) are set out. A rotation of sector structures of several types of LSMF was studied analysing evolution of their primary (main) rotation periods. It is confirmed the changing of Sun's rotation regime in the middle of century XX.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html