Large-Scale Velocity Fields and Small-Scale Magnetic Fields During the Maximum of Solar Cycle 22

Abstract

The key accomplishments from the research during FY 1991 were: (1) the finding by K. Harvey and P. Foukal that the photospheric network is the third significant component that accounts for observed variations in the total solar irradiance; (The first previously recognized component is the temporary decreases due to sunspots and the second is variation due to plage brightness.) (2) the K. Harvey results from studying magnetic flux over the solar cycle: (a) increases in the total magnetic flux by a factor of 4 to 5 from solar minimum to solar maximum with the variation from active regions flux (>25 Gauss) by more than a factor of 20 from cycle minimum to maximum while the variation from quiet sun fields (<25 Gauss) was no more than a factor of 2. (b) interpretation of (a) as meaning that more than 70% of the magnetic flux in active regions disappears without dispersing, (c) slower decreases of weak fields in phase with the decrease in strong fields, and (d) irregular pulses of new flux which appear to be primarily associated with active region complexes.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1992
Accession Number
ADA258172

Entities

People

  • K. L. Harvey
  • Sara F. Martin

Organizations

  • California Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Astronomy
  • Atmospheres
  • California
  • Coronal Mass Ejections
  • Observatories
  • Photosphere
  • Physics
  • Solar Activity
  • Solar Atmosphere
  • Solar Cycle
  • Solar Observatories
  • Solar Physics
  • Southern Hemisphere
  • Stratified Fluids
  • Sun
  • Sunspots

Fields of Study

  • Physics

Readers

  • Mathematics or Statistics
  • Solar Physics