Carrington Maps of the Upper Photosphere

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

7

Interplanetary Medium, Sun: Activity, Sun: Magnetic Fields, Sun: Photosphere

Scientific paper

We have used images of the Sun's disk, obtained in the 6767 Å continuum with the Michelson Doppler Interferometer (MDI) on the Solar and Heliospheric Observatory (SOHO), to make Carrington maps of the upper photosphere during the years 1996-2005. Each map is constructed from observations near the limb where the continuum radiation originates relatively high in the photosphere and faculae have their greatest visibility. Consequently, the Carrington maps resemble spectroheliograms in temperature-sensitive photospheric lines and show the global distribution of faculae and all but the smallest sunspots (which are obscured by overlying faculae). A time-lapse sequence of the combined east-limb and west-limb maps shows the emergence of active regions and the evolution of large-scale patterns of faculae with an average temporal resolution of 14 days during the sunspot cycle. Also, a longitudinally averaged butterfly diagram of these maps shows that in each hemisphere there is a facula-free zone separating the old-cycle polar field from trailing-polarity flux that is migrating poleward from the sunspot belts. These facula-free zones coincide with the neutral zones of the axisymmetric component of photospheric magnetic field and their arrival at the poles in 2001 marks the reversal of the polar fields. We think that this mapmaking technique can be applied to white-light images obtained daily at the Mount Wilson Observatory since 1905 and that the resulting Carrington maps will provide details about the polar-field reversal process during past sunspot cycles when high-quality magnetograms were unavailable.

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

Carrington Maps of the Upper Photosphere 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 Carrington Maps of the Upper Photosphere, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carrington Maps of the Upper Photosphere will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1158285

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