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101.
Zusammenfassung Die Ergebnisse der Radar-Echo-Messungen von I. I. Shapiro, welche auf eine Verringerung der Lichtgeschwindigkeit beim Vorübergang des Lichtes an der Sonne hinweisen, werden zusammen mit der Ablenkung des Lichtes und der Verschiebung seiner Spektrallinien wellentheoretisch erklärt. Es genügt hierzu die Annahme eines materiellen lichtwellentragenden Mediums mit einer Dichte unterhalb des empirischen Vakuums; das Medium muss dann radial zur Sonne eine geringe Inhomogenität besitzen, die in entsprechenden kleinen Zusatzgliedern in den Maxwellschen Gleichungen ihren Ausdruck findet.Auf protophysikalischer Grundlage aufbauend wird die Phasengleichung (22) der an der Sonne vorbeigehenden Lichtwellen unter einfachsten Annahmen abgeleitet und integriert; als Resultat ergeben sich die drei genannten Effekte in Übereinstimmung mit der Erfahrung (Gleichung (39), (44), (47)).
Shapiro (1968) published the first results of radar-echo-observations on Venus and Mercury in the neighbourhood of upper conjunctions with the Sun; the observations indicate a decrease of the velocity of light passing the Sun. The theory of Soldner is disproved; and the general relativity is in accord with the observed facts. But not this theory alone. In this publication the deflection of light, decrease of the velocity of light, and displacement of spectral-lines are explained with the aid of a wavetheory. Hereby the assumption of a material medium carrying light-waves is sufficient, the density of which is below that of the empirical vacuum; hence, the medium must have a small inhomogeneityh radial to the Sun, and the Maxwell equations contain small additional terms (Equation (3)). They lead to the field equations (4) and (5). The protophysical fundamentals of the wave-theory (6), (8), (9), (10a) lead to the Equations (12) of wave-phase. If we assume that the behaviour of the light passing the Sun is independent (in first approximation) from the wave-form (F), the Equation (22) of wave-phase, is deduced for simple-periodic waves of light. Figure 1 outlines the slope and deflection of the ray of light by the Sun. Section 5 contains the solution of (22); and Section 6 the results. The constant of inhomogeneity =1/210–5 (of the radius of the Sun) produces a deflection (39) of light passing the Sun. The length of waves of the light approaching the Sun is decreased to a minimum and is increasing with increasing distance from the Sun until the former value ((43) and (44)). The velocity of light approaching the Sun is decreased to a minimum and increases with increasing distance from the Sun to its former value ((46) and (47)).
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102.
Özgüç  Atila  Üçer  Cumhure 《Solar physics》1988,114(1):141-146
The north-south asymmetry has been studied using the green emission corona brightness in the period of 1947–1976. (N - S)/(N + S) values are constructed with the 5-deg opposite coronal belts brightnesses between ± 5 and ± 60 deg. Power spectra analyses were performed to study periodicities of these (N - S)/(N + S) values. Two noticeable periodicities (14.5 and 5 yr) have been found.  相似文献   
103.
New observations of the umbral limb-darkening are presented. We find a real and significant decrease in the umbra/photosphere intensity ratio towards the limb. This result contrasts the findings of previous authors and we believe this to be the first time such a decrease is reported. Our conclusion is based on broad band pinhole photometer intensity observations of 22 large sunspots covering the spectral region 0.387–2.35 m. The data are selected from measurements on approximately 600 days during the last 15.5 yr. The application of the limb-darkening data to the study of the temperature stratification in the umbra is briefly discussed. The observations confirm the suggestion that the umbra/photosphere intensity ratio seems to be a linear function of the phase in the solar cycle.  相似文献   
104.
Independent Component Analysis (ICA) represents a higher-order statistical technique that is often used to separate mixtures of stochastic random signals into statistically independent sources. Its benefit is that it only relies on the information contained in the observations, i.e. no parametric a-priori models are prescribed to extract the source signals. The mathematical foundation of ICA, however, is rooted in the theory of random signals. This has led to questions whether the application of ICA to deterministic signals can be justified at all? In this context, the possibility of using ICA to separate deterministic signals such as complex sinusoidal cycles has been subjected to previous studies. In many geophysical and geodetic applications, however, understanding long-term trend in the presence of periodical components of an observed phenomenon is desirable. In this study, therefore, we extend the previous studies with mathematically proving that the ICA algorithm with diagonalizing the 4th order cumulant tensor, through the rotation of experimental orthogonal functions, will indeed perfectly separate an unknown mixture of trend and sinusoidal signals in the data, provided that the length of the data set is infinite. In other words, we justify the application of ICA to those deterministic signals that are most relevant in geodetic and geophysical applications.  相似文献   
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108.
The age and thermal history of Cerro Rico de Potosi, Bolivia   总被引:1,自引:0,他引:1  
 Cerro Rico de Potosi, Bolivia, is the world’s largest silver deposit and has been mined since the sixteenth century for silver, and for tin and zinc during the twentieth century, together with by-product copper and lead. The deposit consists primarily of veins that cut an altered igneous body that we interpret to be a dacitic volcanic dome and its underlying tuff ring and explosion breccia. The deposit is compositionally and thermally zoned, having a core of cassiterite, wolframite, bismuthinite, and arsenopyrite surrounded by a peripheral, lower-temperature mineral assemblage consisting principally of sphalerite, galena, lead sulfosalt, and silver minerals. The low-temperature assemblage also was superimposed on the high-temperature assemblage in response to cooling of the main hydrothermal system. Both the dacite dome and the ore fluids were derived from a larger magmatic/hydrothermal source at depth. The dome was repeatedly fractured by recurrent movement on the fault system that guided its initial emplacement. The dome was extruded at 13.8±0.2 Ma (2σ), based on U-Th-Pb dating of zircon. Mineralization and alteration occurred within about 0.3 my of dome emplacement, as indicated by a 40Ar/39Ar date of 13.76±0.10 Ma (1σ) for sericite from the pervasive quartz-sericite-pyrite alteration associated with the main-stage, high-temperature, mineralization. The last thermal event able to reset zircon fission tracks occurred no later than 12.5±1.1 Ma (1σ), as indicated by fission-tract dating. Minor sericite, and magmatic-steam alunite veins, were episodically formed around 11 Ma and between 8.3 and 5.7 Ma; the younger episodes occurring at the time of extensional fracturing at Cerro Rico and widespread volcanism in the adjacent Los Frailes volcanic field. None of these younger events appear to be significant thermal/mineralizing events; the exceptionally flat thermal release pattern of 39Ar from sericite and the results of the fission-tract dating of zircon show that none of the younger events was hot enough, and lasted long enough, to cause significant loss of Ar or annealing of zircon fission tracks. U-Th-Pb dating of zircon cores indicates a Precambrian progenitor for some zircons, and REE analyses of dated samples of hydrothermally altered dacite show the presence of a prominent positive Eu anomaly, which constrains interpretations of the origin and evolution of the magmatic/hydrothermal system. Received: 14 October 1995/Accepted: 29 January 1996  相似文献   
109.
Sütterlin  P.  Wiehr  E. 《Solar physics》2000,194(1):35-42
We have applied the technique of speckle masking to spectra. The observation of elongated solar structures avoids the problem of missing information in one-dimensional spectra. Image motion perpendicular to the slit was diminished by a one-dimensional image stabilization system. The remaining influence of the Earth's atmosphere was removed by a modified speckle-masking algorithm, adapted to the single spatial dimension occurring in the spectra. The reconstructed spectra achieve the diffraction limit of the telescope and the spectrograph.The first application of this technique to observations of spicules and penumbral filaments reveals more details and also yield line profiles which differ from those before reconstruction. The H emission in spicules shows line-of-sight velocities two times larger than in the unprocessed spectra. The non-magnetic line Fe 709.03 nm shows penumbral line widths, reflecting mostly the line asymmetry from the Evershed effect, which are tightly correlated to the continuum intensity fluctuations. Our reconstruction increases the coherence between both from 0.6 to 0.8.  相似文献   
110.
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