AAS 195th Meeting, January 2000
Session 107. The Sun
Display, Saturday, January 15, 2000, 9:20am-4:00pm, Grand Hall

[Previous] | [Session 107] | [Next]


[107.04] Evaluation of Solar Activity in Multiple Spectral Lines, 1994-1998

J. C. Hall, G. W. Lockwood (Lowell Observatory)

We present a method for evaluating solar and stellar activity in terms of the ensemble behavior of many related spectral lines, rather than using just the classic chromospheric proxy lines such as Ca II H&K. Manifestations of solar and stellar activity that are undetectable in a single spectral line become apparent when many lines are used in tandem. The resulting activity indices (1) allow us to examine solar activity with greater precision than would otherwise be possible and (2) allow us to make meaningful comparisons between the Sun and individual solar analogs. In this poster, we show how these indices have reliably tracked solar activity through the Cycle 22/23 minimum. This work is supported by a grant from the National Science Foundation.


[Previous] | [Session 107] | [Next]