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1.
We determine empirical damping constants for 73 selected Fe i lines following the method of Gurtovenko and Kondrashova (1980), employing high-quality observations and the accurate list of Fe i oscillator strengths by Gurtovenko and Kostik (1980).The results show: (i) No increase of the enhancement factor to van der Waals broadening with excitation potential, as predicted by Edmunds (1975), and with the frequency of the transition (Figure 1); (ii) a substantial part of the commonly-used enhancement factor for weaker lines is not due to collisional damping (Figure 2), but to a misrepresentation of the inhomogeneous structure of the deep photosphere. This false damping effect is not seen in the stronger lines which yield an average damping constant : 1.36 1.5 6. 相似文献
2.
E. A. Gurtovenko 《Solar physics》1971,16(2):413-416
Unusual and intense emission in the D
1, D
2 lines has been registered photoelectrically in an undisturbed region near the center of the solar disk on 28 July, 1966. Various aspects of the possibility that the emission might originate in either artificial or natural comets by processes of resonance scattering or flu orescence have been analyzed. It is shown that the observed emission can only be located on the solar surface. Some aspects of the problem are discussed briefly. 相似文献
3.
The Goldberg-Unno method is analysed. Accounting for the instrumental profile correction reduces the derived microturbulent velocities only slightly. A similar effect may be caused by an unresolved macroturbulence. The method of accounting for the damping effect is considered. The correction for the influence of the damping effect does not change substantially the general trend of the variation of
t with 0. The microturbulent velocity
t is reduced appreciably.An attempt to analyse the microturbulent velocities by the Goldberg-Unno method under deviation from LTE is made.The main conclusion is that the Goldberg-Unno method, especially in its modified form, is valid and useful. 相似文献
4.
E. A. Gurtovenko 《Solar physics》1975,45(1):25-33
Brief consideration is given to the conception of the total photospheric motion field. A synthesis of the most thorough investigations is made and the radial (V rad) and tangential (V tg) components of the velocity amplitude of the total photospheric motion field are deduced. At depth logτ5 = ?3.0 V rad and V tg have average values of 1.2 and 1.7 km s?1 respectively. They increase smoothly with depth and reach their maximum values of V rad=3.0, V tg=3.4 km s?1 at depths logτ5= ?0.2 and logτ5 = +0.4 respectively. In the deep photospheric layers both components seem to decrease with depth. 相似文献
5.
The spectrum of the solar corona obtained during the eclipse of 7 March, 1970 has been studied. From the analysis of the line halfwidths it is concluded that the emission of coronal lines of various groups arises in different volumes of the corona. The lines 5303 and 4231 are analyzed in detail and by the use of the equations of excitation and ionization balance. The distribution of electron temperature T
e and density n
e vs height in the solar corona has been found. The usually adopted n
e and T
e are noticeably less than those values obtained in present analysis. This discrepancy may be due to the fact that the considered area of the corona seems to be in an unusual condition. 相似文献
6.
7.
A new crossing method for the study of turbulent velocities in solar and stellar photospheres is considered. The method does not need knowledge of the abundance and oscillator strengths for determining the microturbulent velocity, if the macroturbulent velocity is adopted; or it allows investigation of the micro- and macro-velocities simultaneously, if the abundance and oscillator strengths are known. Using the crossing method for 200 lines of neutral iron we obtain microturbulent velocities for a large range of depths in the solar photosphere. The distribution of macroturbulent velocities with depth is also investigated. The total velocity field calculated from the obtained micro- and macro-velocities agrees with previous results from independent methods. This demonstrates the reliability of using the crossing method for separate determination of the micro- and macroturbulent velocities in solar and stellar atmospheres. 相似文献
8.
By the analysis of the profiles of 20 weak lines observed at five centre-to-limb positions on the solar disk, radial and tangential components of the velocity amplitude of the photospheric motion field are derived in the range of optical depth - 3.0 ? lgτ5 ? +0.5.
相似文献9.
The effective depths of formation of some typical Fraunhofer lines, calculated by the methods suggested by Gurtovenko et al. (1974), Beckers and Milkey (1975), and Makita (1977) are compared. 相似文献
10.
E. A. Gurtovenko 《Solar physics》1967,1(3-4):389-396
A peculiar brightening was observed near the centre of the D2 line of Nai on July 28, 1966, in a position where no activity could be seen in the H line but where a new important active region formed during the next rotation of the sun. The brightening, first observed at 06:30 UT, progressively faded and disappeared before 07:10 UT. 相似文献