This paper reports the results of a survey of Doppler shift oscillations measured during solar flares in emission lines of S xv and Ca xix with the Bragg Crystal Spectrometer ( BCS ) on Yohkoh .
Data from 20 flares that show oscillatory behavior in the measured Doppler shifts have been fitted to determine the properties of the oscillations .
Results from both BCS channels show average oscillation periods of 5.5 \pm 2.7 minutes , decay times of 5.0 \pm 2.5 minutes , amplitudes of 17.1 \pm 17.0 km s ^ { -1 } , and inferred displacements of 1070 \pm 1710 km , where the listed errors are the standard deviations of the sample means .
For some of the flares , intensity fluctuations are also observed .
These lag the Doppler shift oscillations by 1 / 4 period , strongly suggesting that the oscillations are standing slow mode waves .
The relationship between the oscillation period and the decay time is consistent with conductive damping of the oscillations .