A Procedure for the Automated Detection of Magnetic Field Inversion in SOHO MDI Magnetograms

نویسندگان

  • Stanley S. Ipson
  • Valentina V. Zharkova
  • Sergei I. Zharkov
  • Ali Benkhalil
چکیده

Magnetic inversion lines are generally constructed from line-of-sight magnetic field data which have been smoothed to reduce the resolution scale of the data. This eliminates the fine details of the magnetic inversion lines found in regions of strong magnetic field. The paper presents a new approach to constructing magnetic neutral lines, based on a distance transform, which aims to construct neutral lines retaining fine detail in regions of strong magnetic field while reducing the detail elsewhere. The method of implementation is described and results obtained are compared with those obtained by applying Gaussian smoothing to solar magnetograms and with filaments visible in an Hα image for 2002 July.

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تاریخ انتشار 2004