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51.
M. Siarkowski J. Sylwester G. Bromboszcs V. V. Korneev S. L. Mandelshtam S. N. Oparin A. M. Urnov I. A. Zhitnik 《Solar physics》1982,81(1):63-68
In part III of the paper containing the analysis of the INTERCOSMOS 16 ADP spectra, it is shown that by assuming the existence of a small admixture (1%) of non-thermal electrons in the active-region plasma it is possible to improve the agreement between measured and calculated fluxes for some spectra. The analysis follows the suggestion contained in the paper by Karev et al. (1980). 相似文献
52.
M. Siarkowski J. Sylwester J. Bąkała Ż. Szaforz M. Kowaliński Z. Kordylewski S. Płocieniak P. Podgórski B. Sylwester W. Trzebiński M. Stȩślicki K. J. H. Phillips O. V. Dudnik E. Kurbatov V. D. Kuznetsov S. Kuzin I. V. Zimovets 《Experimental Astronomy》2016,41(3):327-350
Interhelioprobe (IHP), an analogue to the ESA Solar Orbiter, is the prospective Russian space solar observatory intended for in-situ and remote sensing investigations of the Sun and the inner heliosphere from a heliocentric orbit with the perihelion of about 60 solar radii. One of several instruments on board will be the Bragg crystal spectrometer ChemiX which will measure X-ray spectra from solar corona structures. Analysis of the spectra will allow the determination of the elemental composition of plasma in hot coronal sources like flares and active regions. ChemiX is under development at the Wroc?aw Solar Physics Division of the Polish Academy of Sciences Space Research Centre in collaboration with an international team (see the co-author list). This paper gives an overview of the ChemiX scientific goals and design preparatory to phase B of the instrument development. 相似文献
53.
The RESIK instrument on the CORONAS-F spacecraft obtained solar flare and active-region X-ray spectra in four channels covering the wavelength range 3.8?–?6.1 Å in its operational period between 2001 and 2003. Several highly ionized silicon lines were observed within the range of the long-wavelength channel (5.00?–?6.05 Å). The fluxes of the Si?xiv Ly-β line (5.217 Å) and the Si?xiii 1s 2?–?1s3p line (5.688 Å) during 21 flares with optimized pulse-height analyzer settings on RESIK have been analyzed to obtain the silicon abundance relative to hydrogen in flare plasmas. As in previous work, the emitting plasma for each spectrum is assumed to be characterized by a single temperature and emission measure given by the ratio of emission in the two channels of GOES. The silicon abundance is determined to be A(Si)=7.93±.21 (Si?xiv) and 7.89±.13 (Si?xiii) on a logarithmic scale with H=12. These values, which vary by only very small amounts from flare to flare and times within flares, are 2.6±1.3 and 2.4±0.7 times the photospheric abundance, and are about a factor of three higher than RESIK measurements during a period of very low activity. There is a suggestion that the Si/S abundance ratio increases from active regions to flares. 相似文献
54.
Szymon Gburek Janusz Sylwester Miroslaw Kowalinski Jaroslaw Bakala Zbigniew Kordylewski Piotr Podgorski Stefan Plocieniak Marek Siarkowski Barbara Sylwester Witold Trzebinski Sergey V. Kuzin Andrey A. Pertsov Yurij D. Kotov Frantisek Farnik Fabio Reale Kenneth J. H. Phillips 《Solar physics》2013,283(2):631-649
Solar Photometer in X-rays (SphinX) was a spectrophotometer developed to observe the Sun in soft X-rays. The instrument observed in the energy range ≈?1?–?15 keV with resolution ≈?0.4 keV. SphinX was flown on the Russian CORONAS–PHOTON satellite placed inside the TESIS EUV and X telescope assembly. The spacecraft launch took place on 30 January 2009 at 13:30 UT at the Plesetsk Cosmodrome in Russia. The SphinX experiment mission began a couple of weeks later on 20 February 2009 when the first telemetry dumps were received. The mission ended nine months later on 29 November 2009 when data transmission was terminated. SphinX provided an excellent set of observations during very low solar activity. This was indeed the period in which solar activity dropped to the lowest level observed in X-rays ever. The SphinX instrument design, construction, and operation principle are described. Information on SphinX data repositories, dissemination methods, format, and calibration is given together with general recommendations for data users. Scientific research areas in which SphinX data find application are reviewed. 相似文献
55.
Environmental and land use factors affecting phosphate hysteresis patterns of stream water during flood events (Carpathian Foothills,Poland) 总被引:1,自引:0,他引:1
Flood events play a substantial role in the circulation of catchment phosphate (PO43?). The purpose of the research was to analyze the factors determining PO43? hysteresis patterns (direction and width) during four types of floods: short and long rainfall floods and snowmelt floods on frozen and thawed soil. The research took place in small catchments (forested, agricultural, mixed‐use) in the Carpathian Foothills in Poland. Anticlockwise hysteresis was identified in the forested catchment during short and long rainfall floods. Under the same conditions, the clockwise direction was observed in the agricultural catchment. In the mixed‐use catchment, the direction of PO43? hysteresis loops was various, driven by the share of water flowing from each part of the catchment. For snowmelt floods, the PO43? hysteresis pattern was similar in all the streams studied (usually clockwise). The direction of PO43? hysteresis loops depends on water circulation patterns, which are determined by the different influx times of particular runoff components. The stream recharge mechanism during a flood event is affected both by the factor initiating the event (precipitation, snowmelt) as well as by land use in the given catchment. Hysteresis loop width was determined by the pool of PO43? in a given catchment during the time period immediately preceding a flood event as well as by the quantity of PO43? flushed out of the soil. The greater a catchment's pool of PO43? and the greater its ability to flush PO43? out of the soil and into surface flow, the wider the hysteresis loops. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
56.
57.
M. Gryciuk M. Siarkowski J. Sylwester S. Gburek P. Podgorski A. Kepa B. Sylwester T. Mrozek 《Solar physics》2017,292(6):77
A new methodology is given to determine basic parameters of flares from their X-ray light curves. Algorithms are developed from the analysis of small X-ray flares occurring during the deep solar minimum of 2009, between Solar Cycles 23 and 24, observed by the Polish Solar Photometer in X-rays (SphinX) on the Complex Orbital Observations Near-Earth of Activity of the Sun-Photon (CORONAS-Photon) spacecraft. One is a semi-automatic flare detection procedure that gives start, peak, and end times for single (“elementary”) flare events under the assumption that the light curve is a simple convolution of a Gaussian and exponential decay functions. More complex flares with multiple peaks can generally be described by a sum of such elementary flares. Flare time profiles in the two energy ranges of SphinX (1.16?–?1.51 keV, 1.51?–?15 keV) are used to derive temperature and emission measure as a function of time during each flare. The result is a comprehensive catalogue – the SphinX Flare Catalogue – which contains 1600 flares or flare-like events and is made available for general use. The methods described here can be applied to observations made by Geosynchronous Operational Environmental Satellites (GOES), the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and other broad-band spectrometers. 相似文献
58.
The Bent Crystal Spectrometer (BCS) onboard the NASA Solar Maximum Mission was part of the X-ray Polychromator, which observed numerous flares and bright active regions from February to November 1980, when operation was suspended as a result of the failure of the spacecraft fine-pointing system. Observations resumed following the Space Shuttle SMM Repair Mission in April 1984 and continued until November 1989. BCS spectra have been widely used in the past to obtain temperatures, emission measures, and turbulent and bulk flows during flares, as well as element abundances. Instrumental details including calibration factors not previously published are given here, and the in-orbit performance of the BCS is evaluated. Some significant changes during the mission are described, and recommendations for future instrumentation are made. Using improved estimates for the instrument parameters and operational limits, it is now possible to obtain de-convolved calibrated spectra that show finer detail than before, providing the means for improved interpretation of the physics of the emitting plasmas. The results indicate how historical archived data can be re-used to obtain enhanced and new, scientifically valuable results. 相似文献
59.
Maciej Pawlikowski Witold P. Alexandrowicz Ladislav Banesz Josef Hromada Janusz K. Kozlowski Krzysztof Sobczyk Barbara Kazior 《Geoarchaeology》1998,13(6):565-594
Moravany-Lopata, located in the complex of sites in the middle Vah basin, dates to the period immediately preceding the LGM. The authors use this site to demonstrate the usefulness of mineralogical, sedimentological, palaeomalacological, and anthropogenic criteria for the correlation of loess profiles. This analysis is especially concerned with sites in loess territories where the loess layers covering archaeological levels are not thick. Such sites occur frequently on the plateaus of the northern part of Central Europe, though they appear most notably in the areas in which the last loess cover, corresponding to the period after the last Pleniglacial and/or Late Glacial postloess sediments, is absent. The archaeological levels dated to before or directly after the LGM occur in the upper portion of the loess, overlain by the Holocene soil. The investigations at the Moravany-Lopata site have confirmed the usefulness of the anthropogenic indicators in the 0.1–1.0 mm fraction for the identification of occupation levels extending even beyond the area of occurrence of macrofinds and evident type structures. On this basis, a relationship could be established between two occupational levels and two ice-wedge generations in the period from 21.4 to 20 ky. Gravettian settlement in western Slovakia seems to have persisted up to the maximum of the LGM. Population groups representing the end of the shouldered points horizon (pointes à cran) appeared in western Slovakia in the intervals between the formation of large networks of ice wedges. The next settlement phase in that territory falls at about 18–17 ky B.P. This is the Epigravettian settlement, which is culturally unrelated to the shouldered points horizon. © 1998 John Wiley & Sons, Inc. 相似文献
60.
OSL‐based chronostratigraphy of river terraces in mountainous areas,Dunajec basin,West Carpathians: a revision of the climatostratigraphical approach
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Janusz Olszak Grzegorz Adamiec 《Boreas: An International Journal of Quaternary Research》2016,45(3):483-493
The technique of optically stimulated luminescence (OSL) dating applied to fluvial sediments provided a geochronological framework of river terrace formation in the middle part of the Dunajec River basin – a reference area for studies of evolution of river valleys in the northern part of the Carpathians (West Carpathians). Fluvial sediments at 18–90 m above valley bottoms were dated in the valleys of the Dunajec River and one of its tributaries. The resulting ages range from 158.9±8.3 to 12.2±1.3 ka. This indicates that some of the terrace sediments were deposited much later than previously assumed on the grounds of a combined morphostratigraphical and climatostratigraphical approach. The OSL‐based chronostratigraphy of terrace formation consists of seven separate phases of fluvial aggradation, separated by periods of incision and lateral erosion. Some of the ages determined correspond to warm stages of the Pleistocene – Marine Isotope Stage 3 (MIS 3) and MIS 5 – demonstrating that some terraces were formed during interstadial or interglacial periods. The results provide a key for evaluating rates of neotectonic uplift, allowing us to decipher the response of a fluvial system to climate change within the context of the glacial–interglacial scheme. 相似文献