No abstract available

[en] A possibility of studying the solar activity and solar cosmic rays in the past by means of cosmogenic isotopes is considered. Attention is paid to a considerable increase in the accuracy of the radiocarbon method. A revealed correlation between the solar sunspots and the cosmic ray flux makes it possible to study the time history of the latter. Neutron production and the rate of ¹⁴C generation in the Earth atmosphere, the intensity of cosmic rays at minima of solar activity and an increase in the ¹⁴C concentration in the atmosphere of the Earth are discussed. Time characteristics of the exchange reservoir of radiocarbon in the atmosphere of the Earth are considered as a part of the general problem

[en] Study of cosmic ray intensity on the basis of the cosmogeneous radiocarbon concentration in the Earth's atmosphere is presented for various time period. The period considered are: modern time, the extremely low solar activity periods, thousands and tens of thousand years time scale. The solar activity effect on the cosmogeneoUs radiocarbon abundance and the possibility to determine the characteristics of 11 year and secular solar activity cycles are considered. It is shown that dynamical characteristics of the solar activity and cosmic ray intensity can be derived from radiocarbon abundance during maximum-minimum transition of the geomagnetic field

[en] Harmonic spectral analysis of change of radiocarbon concentration on the Earth atmosphere during the last 7000 years, including time intervals of both high and low intensity of the Earth magnetic field, was conducted. The effect of geomagnetic field on a harmonic amplitudes and frequencies in variations of radiocarbon concentration, conditioned by solar activity, was shown

[en] Stationary models of ¹⁴C distribution in the troposphere and stratosphere have been investigated. Main photochemical reactions in atmosphere are taken into account. One-dimensional transport of molecules by vertical turbulent diffusion is supposed. The expected ¹⁴CO and ¹⁴CO₂ concentrations in the Earth atmosphere have been evaluated with account for biosphere and ocean as ¹⁴CO₂ sources and drains. Two cases are considered and compared: oxidation of the atomic cosmogenic ¹⁴C up to ¹⁴CO₂ through the ¹⁴CO cycle and instant oxidation of ¹⁴C up to ¹⁴CO₂. In the case of instantaneous oxidation of ¹⁴C up to ¹⁴CO₂ the ''cosmogenic'' ¹⁴CO₂ content in the troposphere is less and in the stratosphere is more than in the case of oxidation through the ¹⁴Co cycle. The ''cosmogenic'' ¹⁴CO content in atmosphere at all altitudes prevails over the ''biosphere'' ¹⁴Co content. It is concluded on the possibility of studying cosmic source by means of ¹⁴Co measurements in atmosphere to day

[en] The connection of content varieties of ¹4^C dependence from changing ofgeomagnetic field intensity was investigated in this article by authors

[en] Presented are the results of studying the effect of long-term cyclic variations in the solar activity on the level of radiocarbon (¹⁴C) concentration in the earth atmosphere. Changes in the concentration (Δ ¹⁴C) over the past 4000-7000 years are considered using data on the ¹⁴C concentration in samples of a known age. Estimates are given for the correlation function and for the spectrum of the power of the correlation function of the Δ ¹⁴C series. The results of the study confirm the existence of a secular cycle in the variations of the radiocarbon concentration in the atmosphere of the Earth over the past 4000 - 7000 years. The amplitude of a secular cycle reached 4%. It is concluded that the periodicity of Δ ¹⁴C is due to the effect of 80-90-year solar activity

No abstract available

[en] Radiocarbon content variations in the earth atmosphere were studied using a mathematical model. The so-called exchange reservoir was considered consisting of layers, and the radiocarbon exchange rate at the interfaces between these layers was supposed to be constant. The process of ¹⁴C mixing and exchange in a dynamic system is described by a system of nonhomogeneous 1st order differential equations. The model also accounts for the change in rate of radiocarbon formation in the earth atmosphere due to cosmic and geophysical effects (solar activity, solar cycle, etc.). (J.P.)

[en] Peculiarities of Δ¹⁴C fluctuations of the radiocarbon content in annual rings of trees of several dosens up to the hundreds years in a 8000-year scale are considered. It is shown that in certain melliniums there are considerable periods of Δ¹⁴C extreme variations. Δ¹⁴C cyclic variations with the periods of dosens to hundreds years are singled out. The cycles have the asymmetric rythm: the ¹⁴C content level growth in the samples proceeds quicker than its decrease. The relation of the ¹⁴C concentration variations to the solar activity is discussed