Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-05-22
Solar Phys. 2001, 202, 229
Astronomy and Astrophysics
Astrophysics
12 pages, 14 figures, to appear in Solar Physics. Also available at http://www.uso.ernet.in/~sushant
Scientific paper
Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum. However, the determination of this peak frequency on a spatial scale of a single pixel (8 arc seconds for the GONG data) is limited by the stochastic variations in the power spectrum presumably caused by the stochastic nature of the excitation process. Averaging over a large number of spectra (100 spectra from a 10 $\times$ 10 pixels area) produced stabler spectra. The peak frequencies of 130 such locations were found to be distributed with a FWHM of about 130 $\mu$Hz. A map of the spatial variation of this peak frequency did not show any strong feature with statistically significant deviation from the mean of the distribution. Likewise, the scatter in the peak frequencies masked the detection of magnetic field induced changes in the peak frequency. On a much larger scale, the N latitudes showed a slightly lower value of the peak frequency as compared to the S latitudes, although the difference (25 $\mu$Hz) is barely larger than the {\it rms} spread (20 $\mu$Hz).
Kumar Brajesh
Tripathy Sushant C.
Venkatakrishnan Parameshwaran
No associations
LandOfFree
Search for Spatial Variability in the Solar Acoustic 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 Search for Spatial Variability in the Solar Acoustic Spectrum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Search for Spatial Variability in the Solar Acoustic Spectrum will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-353666