Solar Physics

, Volume 155, Issue 1, pp 45–55 | Cite as

Small-scale clusters of photospheric network bright points and their dependence on the solar cycle phase

  • V. N. Dermendjev
  • R. Muller
  • M. S. Madjarska


The tendency of network bright points (NBPs) to form in their surface distribution non-random, small-scale clusters is studied by a 2-D nearest-neighbours test, based on observational data for the distance between separate NBPs. High-resolution photographs taken from long time series obtained atλ4308 Å with the 50-cm refractor of Pic du Midi Observatory are used. Three different epochs of the solar cycle were chosen. The results obtained suggest that the degree of clustering depends on the solar cycle phase. Supposing that the NBPs are good tracers of the kilogauss small-scale magnetic field, we use them to obtain information about the subphotospheric small-scale magnetic field organisation and its dependence on the solar cycle phase.


Magnetic Field Time Series Observational Data Solar Cycle Cycle Phase 
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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • V. N. Dermendjev
    • 1
  • R. Muller
    • 2
  • M. S. Madjarska
    • 3
  1. 1.Institute of AstronomyBulgarian Academy of SciencesSofiaBulgaria
  2. 2.Observatoire du Pic du MidiBagbères de BigorreFrance
  3. 3.Institute of AstronomyBulgarian Academy of SciencesSofiaBulgaria

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