Weak Emission Lines in the Wings of Solar H and K

作者：Livingston W^*; Wallace L; White O R

来源：Solar Physics, 2011, 270(2): 485-491.

DOI：10.1007/s11207-011-9779-5

• Solar spectrum
• Emission lines
• Chromosphere
• Photosphere
• Cycle variability

The rare-earth ions cerium II, lanthanum II, dysprosium II, and additionally zirconium II and iron II, are seen as weak emission features in the wings of the solar Ca II H and K lines. The strength of these emission lines increases on the disk toward the limb. We provide recent high-resolution observations at disk center and at the limb. The identity of the weak lines is re-worked. We point out the unique role of eclipse spectra in distinguishing between the photospheric and chromospheric origins of emission lines. It is then demonstrated from our full disk (Sun-as-a-Star) and center disk archives, 1974 - 2010, that no activity cycle related signal is evident (save for the H and K lines themselves).

• 出版日期2011-6