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排序方式： 共有6647条查询结果，搜索用时 15 毫秒
961.
Richard C. Altrock Laurence J. November George W. Simon Robert W. Milkey Simon P. Worden 《Solar physics》1975,43(1):33-37
Heights of formation of lines that do not exhibit Zeeman splitting are calculated using an LTE, partial non-LTE, and full
non-LTE approach. Non-magnetic (g=0) lines are valuable for velocity investigations in quiet-Sun magnetic field regions, and a knowledge of their formation
heights is useful for obtaining three dimensional velocity profiles in these regions.
Presently at Sacramento Peak Observatory.
Operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. 相似文献
962.
963.
Verification tests of linear wave propagation models for cases of waves propagating through a refractive focus typically overpredict peak amplitudes in the vicinity of the focus. Using a parabolic equation model for the combined refraction-diffraction of weakly-nonlinear waves [valid for Ursell number Ur < O(1)], we show that, in a particular experiment, much of the discrepancy between laboratory measurements and linear wave model predictions can be accounted for by including the effect of nonlinearity, which is important in the region of the focus. 相似文献
964.
The response function defines the response of line profiles to a depth variation of such atmospheric parameters as velocity, magnetic field and turbulence. The properties of this function are derived and compared with the so-called contribution function.Operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation. 相似文献
965.
966.
A spectrum scanning Stokes polarimeter 总被引：1，自引：0，他引：1
967.
Pressure and temperature dependence of the elastic properties of polycrystalline trevorite (NiFe2O4)
Robert C. Liebermann 《Physics of the Earth and Planetary Interiors》1972,6(5):360-365
Ultrasonic pulse-superposition measurements at 298 K as a function of hydrostatic pressure to 3 kb for polycrystalline trevorite (NiFe2O4; 1.0% porosity) yield values of the isotropic elastic properties as shown in the table to the right. 相似文献
968.
969.
970.
Robert W. Milkey 《Solar physics》1970,14(1):62-76
A geometrical optics technique developed in order to study energy transport by weak fast-mode hydromagnetic shock waves in a non-homogeneous, anisotropic medium has been applied to the problem of the heating of the chromosphere in the regions of intensified magnetic field which occur above the boundaries of supergranular cells. The results of the calculation indicate that there should be a temperature enhancement in the regions of the chromospheric network. This temperature enhancement is advanced as a possible mechanism for the origin of the observed calcium emission network.Publications of the Goethe Link Observatory, Indiana University, No. 106.Presently at Los Alamos Scientific Laboratories, Los Alamos, New Mexico. 相似文献