Variation of lunar sodium emission intensity with phase angle (Paper 94GL01702) 2263
Variation of lunar sodium emission intensity with phase angle (Paper 94GL01702) 2263
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月球钠发射强度随相位角的变化（论文 94GL01702）2263
DOI：
10.1029/94gl01702
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
B. Finlayson‐Pitts
中科院分区：
文献类型：
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作者：
A. Potter;T. J. Morgan;B. Tsurutani;C. W. Ho;E. Smith;M. Neugebauer;B. Goldstein;J. Mok;J. Arballo;A. Balogh;D. Southwood;W. Feldman;J. Gosling;D. McComas;J. Phillips;L. A. Weiss;V. Pizzo;R. Forsyth;T. Hada;A. Barakat;L. A. Barghouthi;S. Mende;G. Swenson;S. Geller;K. Spear;T. L. Palmer;D. Fritts;Ø. Andreassen;I. Lie;R. Vogt;B. Finlayson‐Pitts
我们报告了在月球表面上方的视线中看到的钠发射强度的新测量结果。这些数据显示了对月相的强烈依赖。发射强度从m_xirnRtll在上弦月附近（相位角90 o）到满月附近（相位角0 o）的非常小的值。这表明，钠蒸气从月球表面产生的速率在日下点最大，在接近终结点时变小。然而，接近满月时钠的排放量福尔斯低于太阳光子驱动过程的预期。当月球在满月附近进入地球磁尾时，太阳风通量显著减少，而太阳光子通量却没有减少，因此我们认为太阳风溅射是钠产生的主要过程。月球穿越地球磁尾时的钠外逸层密度。在满月或接近满月时，月球完全被太阳照亮，但它沉浸在地球的磁尾中。然后，地球磁层的屏蔽作用减少了太阳风粒子到表面的通量，但光子通量不受影响。因此，ff溅射是钠产生的主要过程，钠浓度应在满月或接近满月时降低。该测试应用于一组测量。当时的初步结论是，溅射可能不是很重要，因为当月球位于磁尾时，钠密度只下降了大约两倍。我们进行了额外的观察来测试这个概念。我们测量了钠的发射强度附近的hmar表面在一些不同的hmar相位角。这些测量大多是在月球赤道上方进行的，但也有一些是在月球两极上方进行的。这些数据支持太阳风溅射是一个重要的源过程的假设。
We report new measurements of the sodium emission intensity seen in a line of sight just above the surface of the Moon. These data show a strong dependence on lunar phase. The emission intensity decreases from a m_xirnRtll around first quarter (phase angle 90 o) to very small values near full Moon (phase angle 0o). This suggests that the rate of sodium vapor production from the lunar surface is largest at the subsolar point and becomes small near the terminator. However, the sodium emission near full Moon falls below that which would be expected for solar photon-driven processes. Since the solar wind flux decreases substantially when the Moon enters the Earth's magnetotail near full Moon, while the global solar photon flux is undiminished, we suggest that solar wiml sputtering is the dominant process for sodium production. sodium exospheric density as the Moon traverses the Earth's magnetotail. At, or near full Moon, the Moon is fully illuminated by the Sun, but it is immersed in the Earth's magnetotail. Then, the flux of solar wind particles to the surface is reduced by the shielding action of the Earth's magnetosphere, but photon flux is unaffected. Consequently, ff sputtering is a major process for sodium generation, sodium density should be reduced at or near full Moon. This test was applied to one set of measurements. The tentative conclusion at that time was that sputtering was probably not very significant, because the sodium density decreased only about factor of two when the Moon was in the magnetotail. We have performed additional observations to test this concept. We measured the sodium emission intensity near the hmar surface at a number of different hmar phase angles. Most of these measurements were made above the ltmar equator, but a few were done above the lunar poles. These data favor the hypothesis that solar wind sputtering is an important source process.