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1.
M. A. Livshits I. Yu. Grigoryeva I. I. Myshyakov G. V. Rudenko 《Astronomy Reports》2016,60(10):939-948
Multi-wavelength observations and magnetic-field data for the solar flare of May 10, 2012 (04: 18 UT) are analyzed. A sign change in the line-of-sight magnetic field in the umbra of a small spot has been detected. This is at least partly associated with the emergence of a new magnetic field. A hard X-ray flare was recorded at almost the same time, and a “sunquake” was generated by the impact of the disturbance in the range of energy release on the photosphere. A sigmoid flare was recorded at the beginning of the event, but did not spread, as it usually does, along the polarity inversion (neutral) line. SDO/HMI full vectormagnetic-fieldmeasurements are used to extrapolate the magnetic field of AR 11476 into the corona, and to derive the distribution of vertical currents jz in the photosphere. The relationship between the distribution of currents in the active region and the occurrence of flares is quite complex. The expected “ideal” behavior of the current system before and after the flare (e.g., described by Sharykin and Kosovichev) is observed only in the sigmoid region. The results obtained are compared with observations of two other flares recorded in this active region on the same day, one similar to the discussed flare and the other different. The results confirm that the formation and eruption of large-scale magnetic flux ropes in sigmoid flares is associated with shear motions in the photosphere, the emergence of twisted magnetic tubes, and the subsequent development of the torus instability. 相似文献
2.
Chemical composition anomalies of the corona and solar wind (FIP effect) have their origins in the chromosphere. We study the influence of the possible stratification of abundances in the chromosphere on the shape of corresponding strong Fraunhofer line profiles. A rough estimate is made of this influence for some variants of the variation in elemental abundance a
el(m) (m being the column mass). Calculations are made for the K and 8542Å Caii lines in two semi-empirical models of the chromosphere above sunspot umbra. In practice it is difficult to realize a direct search of the FIP effect in the chromosphere for lack of self-consistent theoretical models of the chromosphere required to match observations to them. An attempt is therefore proposed to find indirect signatures of the effect using a statistically significant sample of spectra for different objects, say, sunspots with a different magnetic structure and a different age. 相似文献
3.
A comparison of theoretical and observed Caii H and K line profiles in sunspot umbrae has been made for different sunspot positions on the solar disk. Four semi-empirical static umbral models were used in calculations: the SUNSPOT model of Avrett (1981), and the models of Staude (1982), Maltby et al. (1986), and Severino, Gomez, and Caccin (1994). The models suggested by Avrett, Maltby et al., and Severino, Gomez, and Caccin reproduce the center-to-limb evolution of the shape of observed profiles. The best agreement with profile parameters obtained from observations is given by the Severino, Gomez, and Caccin model. 相似文献
4.
Doklady Earth Sciences - The surname of the second author should read Grigoryeva 相似文献
5.
We examine the implementation of the program-target approach in a comprehensive typology of rural areas. The study has revealed
stratification elements of rural territories and provides groups of areas according to the status of socioeconomic environment
and the development potential and polarization. 相似文献
6.
The ratios I(K
1)/I(H
1) and I(K
3)/I(H
3) were calculated from four semi-empirical models of sunspot umbra. We determined the dependencies of both ratios of such parameters as temperature gradient and atmospheric opacity. A certain influence on the expected ratios I(K
1)/I(H
1) and I(K
3)/I(H
3) can also come from the FIP effect provided it exists in the chromosphere above sunspot umbra. Theoretical and observed values of I(K
1)/I(H
1) and I(K
3)/I(H
3) are compared. It is shown that for one of the sunspots we observed, the values obtained for the ratio I(K
1)/I(H
1) cannot be explained in terms of existing umbra models. 相似文献
7.
N. I. Grigoryeva 《Oceanology》2013,53(2):176-182
As the materials for this project, we used data on the distribution of the larvae of the Asian paddle crab Charybdis japonicus (A. Milne-Edwards, 1861); the spider crabs Hyas coarctatus ursinus (=Hyas ursinus) (Rathbun, 1924), Pugettia quadridens (de Haan, 1839), and Pisoides bidentatus (H. Milne-Edwards, 1873); the samurai crab Paradorippe granulata (=Dorippe granulata) (de Haan, 1841); the pea crab Pinnixa rathbuni (Sakai, 1934); and the porcelain crab Pachycheles stevensii (Stimpson, 1858) in Minonosok Bay of Pos’eta Bay obtained during 2000–2002 and in 2004. The planktonic samples were collected from the last third of May to September. The greatest density of the larvae was observed in May, mid-June, late June-early July, and late July-early August. The greatest densities of the crab larvae and the decapod larvae ranged from 20.4 to 48.2 and from 88.4 to 245.3 specimens/m3. The schedule of the crab larvae’s occurrence in the plankton is provided for the first time. The distribution of the density showed pronounced patchiness. 相似文献
8.
Grigoryeva I. L. Komissarov A. B. Kuzovlev V. V. Chekmareva E. A. 《Water Resources》2019,46(1):S101-S109
Water Resources - The article presents the results of studying the water chemistry and the species structure of phytoplankton and higher aquatic vegetation of the cooling reservoir at the Kalinin... 相似文献
9.
By means of an inversion of H and K Ca ii line profiles the temperature and electron density in the chromosphere above the umbrae of two sunspots have been estimated. The temperature gradient 5 K km–1 exceeds the corresponding values in both quiet regions and plages. At a height of about 1500 km the umbra becomes hotter than the quiet region. At a temperature of about 10000 K the temperature gradient increases sharply. The electron density at 1500 km is approximately the same as that in the quiet chromosphere at the same height. 相似文献
10.
N. I. Grigoryeva 《Oceanology》2009,49(5):663-671
The analysis of the data obtained during the plankton surveys in Possyet Bay (Peter the Great Bay of the Sea of Japan) in
2000–2001 is presented. The larvae of eight crab species were registered in the plankton: the red king crab Paralithodes camtschaticus (Tilesius, 1815), the snow (opilio) crab Chionoecetes opilio (Fabricius, 1780), the Arctic lyre crab Hyas coarctatus ursinus (Leach, 1815), the kelp crab Pugettia quadridens (de Haan, 1839), the helmet crab Telmessus cheiragonus (Tilesius, 1815), the Japanese swimming crab Charybdis japonica (A. Milne-Edwards, 1861), the pea crab Pinnixa rathbuni (Sakai, 1934), and the porcelain crab Pachycheles stevensii (Stimpson, 1858). These species belonged to six families: Lithodidae, Atelecyclidae, Majidae, Portunidae, Porcellanidae,
and Pinnotheridae. The role of the variability of some of the hydrological factors in the meroplankton larvae development
was studied. In May, the crab larvae were found mostly in the open part of the bay. In June, they were transported by the
current to the northern part of the bay. In July, they spread uniformly in all the bay areas; however, patchiness was observed.
The maximal population density of the crab larvae was registered for July and varied from 6.8 to 23.3 ind. m−3. The crab larvae appeared in the plankton in 2000 and 2001 earlier than for the average season. 相似文献