Local Fractional Frequency Shifts Used as Tracers of Magnetic Activity

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

38

Scientific paper

Using data from SOI-MDI (Haber et al., 2000), we compute the local frequencies of high-degree p modes and f modes. The frequencies are obtained through ring-diagram mode fitting. The Dense-Pack data set consists of a mosaic of 189 overlapping tiles, each tracked separately at the surface rotation rate over 1664-min time intervals during the Dynamics Programs. Each tile is 16° square and the tile centers are separated by 7.5° in latitude and longitude. For each sampling day and for each tile, we have computed the frequency shift measured relative to the temporal and spatial average of the entire set of frequencies. The motion of active regions as they rotate across the solar disk is vividly traced by these measurements. Active regions appear as locations of large positive frequency shifts. If the shifts are averaged over the solar disk and are scaled down to the appropriate wave number regime, the magnitude and frequency dependence of the shifts are consistent with the measured changes in global oscillation frequencies that occur over the solar cycle. As with the frequency shifts of low-degree global oscillations, the frequency dependence of the shifts indicates that the physical phenomena inducing the shifts is confined to the surface layers of the Sun.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Local Fractional Frequency Shifts Used as Tracers of Magnetic Activity 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 Local Fractional Frequency Shifts Used as Tracers of Magnetic Activity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local Fractional Frequency Shifts Used as Tracers of Magnetic Activity will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1824589

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.