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Astronomy Reports - A comparison of the virial parameters of galaxies and galaxy clusters (radius, density, and entropy function) in a wide range of masses, $${{10}^{6}} \leqslant... 相似文献
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For perfectly aligned heliostats and coelostats tracking at the solar rate and half the solar rate, respectively, the solar beam has no translational motion. But, particularly in the field at eclipses, it is not possible to align heliostats and coelostats with infinite precision. We derive the effect of small misalignments on the translational motion of the beam, and give tables to allow the calculation of the accuracy to which the instruments must be mounted and adjusted to attain a desired accuracy over a given duration. Further, we show how to derive the necessary adjustments to improve alignment, given measurements of the tracking error. 相似文献
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