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We present the results of the prompt, early and afterglow optical observations of five γ-ray bursts (GRBs): GRB 100901A, GRB 100902A, GRB 100905A, GRB 100906A and GRB 101020A. These observations were made with the Mobile Astronomical System of TElescope-Robots in Russia (MASTER-II Net), the 1.5-m telescope of the Sierra Nevada Observatory and the 2.56-m Nordic Optical Telescope. For two sources, GRB 100901A and GRB 100906A, we detected optical counterparts and obtained light curves starting before the cessation of γ-ray emission, at 113 and 48 s after the trigger, respectively. Observations of GRB 100906A were conducted in two polarizing filters. Observations of the other three bursts gave the upper limits on the optical flux; their properties are briefly discussed. A more detailed analysis of GRB 100901A and GRB 100906A, supplemented by Swift data, provides the following results and indicates different origins for the prompt optical radiation in the two bursts. The light-curve patterns and spectral distributions suggest that there is a common production site for the prompt optical and high-energy emission in GRB 100901A. The results of the spectral fits for GRB 100901A in the range from optical to X-ray favour power-law energy distributions and a consistent value of the optical extinction in the host galaxy. GRB 100906A produced a smoothly peaking optical light curve, suggesting that the prompt optical radiation in this GRB originated in a front shock. This is supported by a spectral analysis. We have found that the Amati and Ghirlanda relations are satisfied for GRB 100906A. We obtain an upper limit on the value of the optical extinction on the host of GRB 100906A. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.

We discuss effective applications of data obtained by both instruments of the Solar Dynamics Observatory: The Helioseismic & Magnetic Imager (HMI) and The Atmospheric Imaging Assembly (AIA). The purpose of this presentation is to show the most important problems of solar activity which are the main subjects in Pulkovo Observatory of the Russian Academy of Science. For these investigations uniform data sets of magnetic fields and coronal emissions in extreme ultra-violet bands are needed. Thus, we are planning to create SDO center in Pulkovo Observatory, which will help us in collaboration with existing SDO centers and provide more effective way of access to data for studies of the Sun.

We present the results of our UBVRI CCD photometry for the second brightest supernova of 2009, SN 2009nr, discovered during a sky survey with the telescopes of the MASTER robotic network. Its light and color curves and bolometric light curves have been constructed. The light-curve parameters and the maximum luminosity have been determined. SN 2009nr is shown to be similar in light-curve shape and maximum luminosity to SN 1991T, which is the prototype of the class of supernovae Ia with an enhanced luminosity. SN 2009nr exploded far from the center of the spiral galaxy UGC 8255 and most likely belongs to its old halo population. We hypothesize that this explosion is a consequence of the merger of white dwarfs. © 2011 Pleiades Publishing, Ltd. This work was supported by the Ministry of Science of the Russian Federation (State contract no. 02.740.11.0249), the “Dynasty” Foundation of noncommercial programs, and the Russian Foundation for Basic Research (project no. 10-02-00249a). IRAF is distributed by the NOAO, which are operated by the AURA, Inc., under contract with the NSF.

Impact of the Large-Scale Solar Magnetic Field on the Solar Corona and Solar Wind

Aims. The present work is the first in a series of articles that develop a new proxy to represent the evolution of magnetic activity in past solar cycles by combining the information from historical Ca II K line spectroheliograms and sunspot magnetic field measurements.Methods. We use synoptic (Carrington) maps from 1915–1985 that were derived from daily Ca K line observations at Mount Wilson Observatory to identify the chromospheric plages and to create synoptic pseudo-magnetograms. We use historical observations of sunspot magnetic fields from 1917 to the present to assign polarity to pixels situated within plages. The original Ca K spectroheliograms are nonuniform in their brightness, and we develop a novel approach to re-normalize their intensities.Results. We show that a homogeneous long-term series of pseudo-magnetograms can be successfully constructed by combining sunspot field measurements and plages with renormalized intensities. In our tests, about 80% of pixels situated within plages showed the same magnetic polarity as the synoptic magnetograms taken with the Kitt Peak Vacuum Telescope. Finally, we discuss possible approaches to further improve the agreement between observed and pseudo-magnetograms.

Presented paper describes the basic principles and features of the implementation of a robotic network of optical telescopes MASTER, designed to study the prompt (simultaneous with gamma radiation) optical emission of gamma-ray bursts and to perform the sky survey to detect unknown objects and transient phenomena. With joint efforts of Sternberg astronomical institute, High altitude astronomical station of the Pulkovo observatory, Ural state university, Irkutsk state university, Blagoveshchensk pedagogical university, the robotic telescopes MASTER II near Kislovodsk, Yekaterinburg, Irkutsk and Blagoveshchensk were installed and tested. The network spread over the longitudes is greater than 6 hours. A further expansion of the network is considered., Comment: Accepted for publication in Experimental Astronomy, 18 pages, 11 figures

We present results of the prompt, early, and afterglow optical observations of five gamma-ray bursts, GRBs 100901A, 100902A, 100905A, 100906A, and 101020A, made with the Mobile Astronomical System of TElescope-Robots in Russia (MASTER-II net), the 1.5-m telescope of Sierra-Nevada Observatory, and the 2.56-m Nordic Optical Telescope. For two sources, GRB 100901A and GRB 100906A, we detected optical counterparts and obtained light curves starting before cessation of gamma-ray emission, at 113 s and 48 s after the trigger, respectively. Observations of GRB 100906A were conducted with two polarizing filters. Observations of the other three bursts gave the upper limits on the optical flux; their properties are briefly discussed. More detailed analysis of GRB 100901A and GRB 100906A supplemented by Swift data provides the following results and indicates different origins of the prompt optical radiation in the two bursts. The light curves patterns and spectral distributions suggest a common production site of the prompt optical and high-energy emission in GRB 100901A. Results of spectral fits for GRB 100901A in the range from the optical to X-rays favor power-law energy distributions with similar values of the optical extinction in the host galaxy. GRB 100906A produced a smoothly peaking optical light curve suggesting that the prompt optical radiation in this GRB originated in a front shock. This is supported by a spectral analysis. We have found that the Amati and Ghirlanda relations are satisfied for GRB 100906A. An upper limit on the value of the optical extinction on the host of GRB 100906A is obtained., Comment: 18 pages, 14 figures, 14 tables, 5 machine readable tables; accepted for publication in MNRAS

Digitized images of full disk CaK spectroheliograms from two solar observatories were used to study cycle variation of ephemeral regions (ERs) over ten solar cycles 14-23. We calculate monthly averaged unsigned latitude of ERs and compare it with annual sunspot number. We find that average latitude of ERs can be used as a predictor for strength of solar cycle. For a short-term prediction (dT about 1-2 years), maximum latitude of ephemeral regions (in current cycle) defines the amplitude of that cycle (higher is the latitude of ERs, larger are the amplitudes of sunspot cycle). For a long-term prediction (dT about 1.5 solar cycles), latitude of ERs at declining phase of n-th cycle determines the amplitude of (n+2)-th sunspot cycle (lower is the latitude of ERs, stronger is the cycle). Using this latter dependency, we forecast the amplitude of sunspot cycle 24 at W=92 +/- 13 (in units of annual sunspot number)., Memorie della Societ\`a Astronomica Italiana, in press

The main goal of the MASTER-Net project is to produce a unique fast sky survey with all sky observed over a single night down to a limiting magnitude of 19 - 20mag. Such a survey will make it possible to address a number of fundamental problems: search for dark energy via the discovery and photometry of supernovas (including SNIa), search for exoplanets, microlensing effects, discovery of minor bodies in the Solar System and space-junk monitoring. All MASTER telescopes can be guided by alerts, and we plan to observe prompt optical emission from gamma-ray bursts synchronously in several filters and in several polarization planes., Comment: 10 pages, 8 figures

Construction of robotic observatories has developed into an important and thriving field of astronomy. Their large field of view combined with the capability to be pointed at any direction makes robotic astronomical systems indispensable for tasks involving searches for transients like GRB, supernovae explosions, novae, and so forth, where both the time and direction of the search are impossible to predict. This paper describes prompt GRB observations made with MASTER-VWF wide-field cameras and the methods of image analysis and classification of transients used for real-time data processing. During seven months of operation six synchronous observations of gamma-ray bursts have been made using MASTER VWF facilities deployed in Kislovodsk and Irkutsk. In all cases high upper limits have been obtained.

At present time Robotic observatory making is of current importance. Having a large field of view and being able to point at anywhere, Robotic astronomical systems are indispensable when they looking for transients like grb, supernovae explosions, novae etc, as it's impossible in these cases to foresee what you should point you telescope at and when. In work are described prompt GRB observations received on wide-field chambers MASTER-VWF, and also methods of the images analysis and transients classifications applied in real-time data processing in this experiment. For 7 months of operation 6 synchronous observations of gamma-ray burst had been made by MASTER VWF in Kislovodsk and Irkutsk. In all cases a high upper limits have been received (see tabl \ref {tab_grbwf} and fig. \ref {allgrb})., Comment: 21 pages, 21 figure, 2 tables, Advances in Astronomy in press

There are the results of gamma-ray bursts observations obtained using the MASTER robotic telescope in 2007 - 2009. We observed 20 error-boxes of gamma-ray bursts this period.The limits on their optical brightnesses have been derived. There are 5 prompt observations among them, obtained at our very wide field cameras. Also we present the results of the earliest observations of the optical emission of the gamma-ray bursts GRB 050824 and GRB 060926., Comment: 10 pages, 2 figures

Analysis of the solar corona structure during the periods of minimum solar activity from 1867 till 2006 has been carried out. A new flattening index for the large coronal streamers has been proposed. It has been shown that the index has been smoothly changing during the last 140 years. The minimal value of the index occurred during activity cycles 17--19; this was the period when the solar corona most of all corresponded to the dipole configuration of the global magnetic field of the Sun. At the beginning of the 20th and the 21st centuries, the corona structure corresponded to the quadrupole configuration. The reasons for the variations in the solar corona structure and its relation to geomagnetic activity are discussed., Comment: 8 pages, 7 figures, 1 table. In proceedings 10-th Pulkovo conference on solar physics,St.Petersburg-2006

Various observatories around the globe started regular full-disk imaging of the solar atmosphere in the Ca II K line since the early decades of the 20th century. The archives made by these observations have the potential of providing far more detailed information on solar magnetism than just the sunspot number and area records to which most studies of solar activity and irradiance changes are restricted. We evaluate the image contents of three Ca II K spectroheliogram time-series, specifically those obtained by the digitization of the Arcetri, Kodaikanal, and Mt Wilson photographic archives. We describe the main problems afflicting these data and analyze their quality by expressing the image contents through several quantities. We compare the results obtained with those for similar present-day observations taken with the Meudon spectroheliograph and with the Rome-PSPT. We show that historic data suffer from stronger geometrical distortions and photometric uncertainties than similar present-day observations. The latter uncertainties mostly originate from the photographic calibration of the original data and from stray-light effects. We also show that the image contents of the three analyzed series vary in time. These variations are probably due to instrument changes and aging of the spectrographs used, as well as changes of the observing programs. Our results imply that the main challenge for the analysis of historic data is their accurate photometric calibration. This problem must be solved before they can provide reliable information about solar magnetism and activity over the last century. Moreover, inter-calibration of results obtained from independent time-series is required to reliably trace changes of solar properties with time from the analysis of such data., Comment: 13 pages, 14 figures, submitted

[1] New solar activity indices for the sunspot cycle minima were obtained from the Hα synoptic charts for 1887–2005, Ca II K observational data of the solar disk at Kodaikanal for 1907–1995. The Apz index determines the area of the polar zone occupied by the magnetic field of one polarity, and A(t) is the sum of squares of dipole and octupole magnetic moments. The L(t) index is the total length of magnetic neutral lines on the Hα synoptic chart, and K(t) characterizes the complexity of the topology pattern of the general magnetic field of the Sun. It is determined by the inverse number of crossings of neutral lines with the meridian net on the Hα chart. The R(t) index characterizes the correlation factor of the magnetic field polarities in the latitude zones ±40◦. The solar rotation index SSPD(t) is determined by the sum of the spectral density of the power of the magnetic field sector structures. The area of the Ca II K bright points at high latitudes is the SK(t) index. It has been shown that the 11-year cycles of Apz(t), A(t), L(t), K(t), R(t), SSPD(t), and SK(t) have maxima at the sunspot activity minimum and that they are ahead of the cycles of Wolf numbers, W (t), by 5–6 years.

The parameter G, which is determined from the general number of sunspots groups Ng according to the daily observations G=Sum(1/Ng)^2, is offered. This parameter is calculated for the days when there is at least one sunspots group. It characterizes the minimum epoch solar activity. Parameter G mounts to the maximum during the epoch close to the minimal activity of sunspots. According too the data of the sequence of sunspots group in Greenwich-USAF/NOAA observatory format, observation data of Kislovodsk solar station and also daily Wolf number the changes of parameter G during 100 years were reconstructed. It is demonstrated in the paper that parameter G's amplitude in minimal solar activity n is linked with the sunspot cycle's amplitude Wn+1. The 24th activity cycle prediction is calculated, which makes W24=135(+/-12)., 5 pages, 5 figures

Duration of the extended solar cycles is taken into the consideration. The beginning of cycles is counted from the moment of polarity reversal of large-scale magnetic field in high latitudes, occurring in the sunspot cycle n till the minimum of the cycle n+2. The connection between cycle duration and its amplitude is established. Duration of the "latent" period of evolution of extended cycle between reversals and a minimum of the current sunspot cycle is entered. It is shown, that the latent period of cycles evolution is connected with the next sunspot cycle amplitude and can be used for the prognosis of a level and time of a sunspot maximum. The 24-th activity cycle prognosis is done. Long-term behavior of extended cycle's lengths is considered., 7 pages, 6 figures, 1 table

After a polar reversal in one hemisphere the Sun has two polar caps of the same sign, leaving it in a kind of monopolar state. It may take months before a polar reversal occurs in the other hemisphere. The situation may have been extreme in the Maunder Minimum where the northern hemisphere most probably did not have polar reversals during several cycles, while the southern hemisphere may have had some. This may affect the interplanetary field and thus the cosmic rays reaching the Earth. Using the relation between the Wolf number and the speed of the global magnetic field regions the yearly mean Wolf number has to exceed 40 in order to have polar reversals, hence per hemisphere we expect that it must exceed 20. This may be used to give a definition of a deep minimum. (c) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

In this work we introduce a new way of binning sunspot group data with the purpose of better understanding the impact of the solar cycle on sunspot properties and how this defined the characteristics of the extended minimum of cycle 23. Our approach assumes that the statistical properties of sunspots are completely determined by the strength of the underlying large-scale field and have no additional time dependencies. We use the amplitude of the cycle at any given moment (something we refer to as activity level) as a proxy for the strength of this deep-seated magnetic field. We find that the sunspot size distribution is composed of two populations: one population of groups and active regions and a second population of pores and ephemeral regions. When fits are performed at periods of different activity level, only the statistical properties of the former population, the active regions, are found to vary. Finally, we study the relative contribution of each component (small-scale versus large-scale) to solar magnetism. We find that when hemispheres are treated separately, almost every one of the past 12 solar minima reaches a point where the main contribution to magnetism comes from the small-scale component. However, due to asymmetries in cycle phase, this state is very rarely reached by both hemispheres at the same time. From this we infer that even though each hemisphere did reach the magnetic baseline, from a heliospheric point of view the minimum of cycle 23 was not as deep as it could have been.

The IX Russian-Finnish Symposium on Radio Astronomy was held in Special astrophysical observatory RAS in Nizhnij Arkhyz, Russia on 15-20 October 2006. It was dedicated to the two-side collaboration in the field of multi-wavelength investigations of solar radio emission, studies of polar regions of the Sun, studies of stellar activity, AGNs, quasars and BL Lac objects in radio bands from millimeter to decimetre wavelengths with RATAN-600, Metsahovi 14m, RT32m radio telescope and VLBI systems. Here abstracts of all forty papers are given. The Web-site of the Symposium is http://cats.sao.ru/~satr/RFSymp/ ., 41 pages, abstracts of the Symposium papers

We discuss long-time changes of polar activity of the Sun using the new observational data sets in the optical range during 1872-2001. A study of the secular and cycle variations of the magnetic activity at the high-latitude regions is the main goal that includes polar magnetic field reversals during 1872-2001 and secular changes of the duration of polar activity cycles. The secular increase of the area of polar zones during the minimum activity in the last 120 years and as consequence a decrease of coronal temperature of the Sun in the high-latitude zones during the last 50 years. Correlation between the polar cycles of CaII-K bright points with the Wolf sunspot numbers cycles, W(t), and the 22-year polar magnetic cycles of CaII-K bright points at the high latitudes during 1905-1995 is discussed.

heights. The maximum brightness of the corona was observed in the equatorial zone in the solar minimum. The drifts of coronal intensity were observed in direction to the poles in the beginning of solar cycle. The maximum brightness of high-latitude corona was observed during the polar magnetic field reversal of the Sun in 1999‐2001. The drifts of low coronal brightness were observed in the opposite direction from high latitudes to the equator after polar magnetic field reversal. The angles of deviation from radial direction of coronal streamers were determined on daily coronal images. It was found that coronal streamers were inclined on the whole to the equator during 1996.5‐1999.5, although after 1999.5 the streamers were inclined to the poles. The angles of nonradial direction of the streamers reached about 10 ‐15 . The longitudinal distribution of coronal brightness at various heights was considered. It was compared with heliosphere neutral layer and with drift of filament bands in an epoch of polar magnetic field reversal of the Sun. INDEX TERMS: 7509 Solar Physics, Astrophysics, and Astronomy: Corona; 7524 Solar Physics, Astrophysics, and Astronomy: Magnetic fields; 7536 Solar Physics, Astrophysics, and Astronomy: Solar activity cycle; KEYWORDS: Solar corona; coronal rays; coronal observations.

We investigate the variations of temperature in the polar corona using the long-term observations of intensity of the coronal lines FeXIV 530.3 nm and FeX 637.4 nm at the high latitudes during 1952-2001. We composed a combined series of the green and red intensities for 1952-2001, using the Kislovodsk data as basis, inserting missing data from other observatories. The mean monthly coronal intensities KI5303 and KI6374 have been calculated in the sunspot (0degrees-45degrees) and in the high-latitude (45degrees-90degrees) zones. We found that the average intensity of KI5303 decreased 1.5 times, while the intensity of KI6374 increased 1.7 times at the high-latitude zone during the last 50 years. The ratio KI6374/KI5303 shows the 22-year cycle of temperature of the polar corona. The average value of KI6374 /KI5303 more than doubled during 1957-2001. It corresponds to a decrease of average coronal temperature at the high latitudes by 0.2 (.) 10(6) K. We argue that a decrease of coronal temperature is connected with the increase (doubling) of the area of the polar zones A(pz) occupied by unipolar magnetic fields (Makarov et al., 2002) and, probably, with an increase of the area of polar coronal holes.

We estimate the magnetic activity of the Sun that will decrease seriously in the next two or three cycles, leading to a deep minimum. Three arguments are given in favor of this statement. With the approach of a deep minimum the Earth ocean temperature may gradually decrease by at least 1degreesK. However, due to the increase of the greenhouse effect one may expect during the coming decennia only a small decrease, say 0.5degreesK. Nevertheless this may be interpreted wrongly as if the greenhouse effect is irrelevant and that the present high ocean temperature is only a casual fluctuation. Governments may then allow an ever increasing use of Earth fuel, leading to an ocean temperature higher than at present after half a century. After the deep minimum an extra increase in temperature of at least 1degreesK is to be expected leading to drastic, if not catastrophic, effects. It is concluded that (1) more research on the activity of the Sun is required as well as more research on the greenhouse effect; (2) the need for nuclear fusion is imperative.

We have computed and analyzed the average latitude per solar rotation of 36 zone boundaries of the large-scale magnetic field, which have been detected by Ha filaments and prominences during 1915-2000. We have found two types of the latitude oscillations of the zone boundaries with the quasi-periods of about 1.3 and 2.3-years (17 and 30 solar rotations). We consider that 1.3-year latitude periodicity of the filament bands connected with the same oscillations at the tachocline (Komm et al. (2000), Howe et al. (2001)). We have found the secular variation or an increase of a period of about 1.3-year oscillations from 1.1 year in 1915 up to 1.4 year in 2000. Second type of the latitude oscillations is about 2.3-year that concerns to quasi-biennial cycle. Properties of 1.3 and 2.3-year latitude oscillations of the filament bands during 1915-2000 are discussed.

The large-scale unipolar zones have boundaries which practically coincide with filament bands encircling the whole Sun. Huge currents flow in these filament bands, which attract or repulse each other. When new unipolar zones are generated near the equator and thus new filament bands appear after a while. The previously existing filament bands feel a new repulsion attraction and a pole-ward motion starts. When a filament band reaches a pole and disappears (polar reversal) it releases the amount of "surface mass" it was holding and this pushes the other filament bands somewhat back, causing a "recoil". A more or less stationary situation may result in the second half of the sunspot cycle (after a polar reversal), in which the filament bands move slightly back an forth of their "equilibrium" latitude. Numerical estimates give reasonable acceleration and velocities, provided the filament bands are loaded by much more mass the they carry themselves: indeed they are anchored in the regions of unipolar field and thus form a connected piece like a sheet which may slip over the Sun.

We calculated the area of polar zones of the Sun, A(pz), occupied by unipolar magnetic field on H,, synoptic magnetic charts, following Makarov (1994), from 1878 to 2000. We found a gradual decrease of the annual latitude of the high-latitude zone boundaries of the global magnetic field of the Sun at the minimum of activity, Theta(2m), from 53degrees in 1878 down to 38degrees in 1996, yielding an average decrease of 1.2degrees per cycle. We found that the area of polar zones of the Sun A(pz) has risen by a factor of 2 during 1878-2000. The area of the unipolar magnetic field at high-latitudes A, may be used as a new index of magnetic activity of the Sun. We compared Apz with the geomagnetic index < aa > and Wolf number W(t). A temperature difference of about 1.3degrees between the Maunder Minimum and the present time was deduced. We have found that the highest latitude of tile polar zone boundaries of the large-scale magnetic field during very low solar activity reaches about 60degrees. It is supposed that the Theta(2m) - latitude coincides with the latitude where partial derivative(r)w = 0, with w (r, sigma) being the angular frequency of the solar rotation. Tile causes of the waxing and waning of the Sun's activity in conditions like Maunder Minimum are discussed.

The gravitational energy associated with variations in the radius of the Sun is huge: with a relative change of 1/2000 (the estimated difference between maximum and minimum solar activity) and taking only the convection zone to expand, corresponds to about 2 10(34)J, which is 1/10 of the total rotational energy of the Sun. Non-radial oscillations with a tiny nonlinearity can still yield energies comparable to or larger than the total magnetic energy of a full sunspot cycle or three or four orders more than the luminosity of the Sun, but that is not sufficient to account for the changes of the temperature on Earth. The expansion of the upper layers of the convection zone, however, may directly or indirectly affect the climate and the biological aspects on the Earth. Moreover this suits a qualitative explanation why the Sun expands during a minimum of the magnetic activity.

Differential rotation of the corona in the lines Fe XIV 5303 Angstrom, Fe X 6374 Angstrom and of the large-scale magnetic fields during 1910 - 1993 was studied. It was shown that bands of slower-than-average rotation arise after polar magnetic field reversals and migrate to the equator during 7 - 15 years along the butterfly diagrams of polar faculae and sunspots. The fastest latitude drift of the bands was observed from 1935 to 1955 and it preceded the maximum activity in the 19-th cycle (1955-1965). Latitude span of the bands of torsional oscillations varies from 0.5R. to 1.3 R. and shows a long-term variation of about 55 years. The reasons of occurrence of the rotation bands and their link with the coronal holes in the global solar pattern are discussed.