Nature of Quiet Sun Oscillations Using Data from the Hinode, TRACE, and SOHO Spacecraft

G. R. Gupta, S. Subramanian, D. Banerjee, M. S. Madjarska, J. G. Doyle

Figure 1. The quietòÀÓSun region observed with the TRACE 1550 Å passband on 9 April 2007. Contour levels show the line-of-sight magnetic field strength ≥ |30| G obtained from the corresponding MDI image. SOT FOV is over-plotted as a rectangular box.

Abstract

We study the nature of quietòÀÓSun oscillations using multi-wavelength observations from TRACE, Hinode, and SOHO. The aim is to investigate the existence of propagating waves in the solar chromosphere and the transition region via analyzing the statistical distribution of power in different locations, e.g. in bright magnetic (network), bright non-magnetic and dark non-magnetic (interòÀÓnetwork) regions, separately. We use Fourier power and phaseòÀÓdifference techniques combined with a wavelet analysis. Two-dimensional Fourier power maps were constructed in the period bands 2òÀÓ4 minutes, 4òÀÓ6 minutes, 6òÀÓ15 minutes, and beyond 15 minutes. We detect the presence of longòÀÓperiod oscillations with periods between 15 and 30 minutes in bright magnetic regions. These oscillations were detected from the chromosphere to the transition region. The Fourier power maps show that shortòÀÓperiod powers are mainly concentrated in dark regions whereas longòÀÓperiod powers are concentrated in bright magnetic regions. This is the first report of longòÀÓperiod waves in quietòÀÓSun network regions. We suggest that the observed propagating oscillations are due to magnetoacoustic waves which can be important for the heating of the solar atmosphere.

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Last Revised: 2012 September 26th