Wave propagation in the solar chromosphere: some new results from CaII K, CaII 8542 and HeI 10830 observations
Time series of spectra taken simultaneously in the three chromospheric lines Ca II 8542 A, Ca II K, and He I 10830 AA are analyzed to study the wave propagation behaviour in the solar chromosphere. The V-V phase difference between the three chromospheric lines stays close to 0 deg in the whole frequency range observed and thus confirms previous observations of a non-propagating component dominating the acoustic wave spectrum in the solar chromosphere. In particular, the dominant 3-min oscillations observed in the core displacement of the Ca II 8542 and Ca K line are highly correlated, contrary to the numerical NLTE radiating shock dynamic simulations of Carlsson and Stein (1993) which revealed a significant phase delay between the two lines. The oscillation amplitude observed in the He 10830 line (RMS ~ 1100 m/s) is only about half the velocity amplitude derived from the core displacement of Ca K3. We also present a first He 10830 k-omega diagram.
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