Solar Physics Division Meeting 2000, June 19-22
Session 1. Helioseismology, Magnetic Fields, Chromosphere and Transition Region
Display, Chair: C. U. Keller, Monday-Thursday, June 19, 2000, 8:00am-6:00pm, Forum Ballroom

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[1.32] Quiet Sun Oscillation Packets

J. Ireland (ESA External Fellow at NASA Goddard Space Flight Center), S. W. McIntosh (High Altitude Observatory, NCAR), B. Fleck (ESA Space Science Department, NASA/GSFC)

This paper combines the novel techniques of wavelet analysis and genetic algorithms to exploit SOHO-SUMER (Solar Ultraviolet Measurements of Emitted Radiation) data in a new way. The data consists of time series in O I 1306.03Å, Si II 1309.28Å, C I 1311.36Å, C II 1334.53Å, He I 584Å, O I 1152Å\, and C III 1176Å\ tracking specific pieces of quiet Sun westward across the disk.

To analyse this data, genetic algorithms (McIntosh et. al, A.& A. Suppl.\ Ser., 132, 145, 1998) are used to fit quiet Sun emission spectra, allowing the unbiassed determination of spectral properties such as total line intensity and Doppler velocity. Time series of line intensity and Doppler velocity are formed which are then analysed using wavelet techniques, permitting the distinguishing of distinct oscillation wave packets in the time series. Correlations of wave packets between different lines and physical quantities are discussed, as are the distributions of oscillation packets seen.

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