Solar cycle changes in the high frequency spectrum

Details Solar cycle changes in the high frequency spectrum Solar cycle changes in the high frequency spectrum

Mar 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994soph..150..389r&link_type=abstract

Solar Physics, vol. 150, no. 1-2, p. 389-392

Physics

21

Calcium, Chromosphere, Frequency Shift, K Lines, Line Spectra, Luminous Intensity, Mathematical Models, Oscillations, Photosphere, Solar Corona, Solar Cycles, Spectrum Analysis, Error Analysis, Fourier Transformation, Helioseismology, Interference, Line Shape, Power Spectra, Spherical Harmonics, Temperature Gradients, Time Series Analysis, Turbulence Effects, Wave Propagation

Scientific paper

We present observations of high frequency, intermediate degree, Ca-K line solar intensity oscillations. We compare the peak frequencies determined from these 1991.4 observations with the peak frequencies from 1987.9 South Pole observations (Duvall et al., 1991) in that portion of the spatio-temporal diagram where the two datasets overlap (degrees between 30 and 150 and frequencies between 4 and 6.6 mHz). We find that temporal changes are detectable in the high frequency spectrum and are particularly large near 5.4 mHz. The m-averaged high frequency peaks decreased in frequency in 1991.4 compared to the peak frequencies measured in 1987.9. The magnitude of the frequency shift is of the order of 10 micro-Hz near 5.4 mHz, increases with degree, and decreases to near zero both above and below 5.4 mHz. It is unlikely that these temporal changes in the high frequency spectrum are due to a change in the height of the subphotospheric acoustic source layer. A physical mechanism for these frequency shifts has not yet been identified.

Affiliated with

Also associated with

No associations

Rating

Solar cycle changes in the high frequency spectrum does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Solar cycle changes in the high frequency spectrum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solar cycle changes in the high frequency spectrum will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1587691