Polarization Studies at 3.8 CM of McMath Region 12417 of 1973,

Abstract

The strong active region McMath 12417 (SFC 158) of 1973 was observed as it moved from the east to the west limb of the sun. The observations were carried out at 3.8 cm in both left and right circular polarization with an antenna beam width of 4.4 arc min. The circular polarization of the region started as negative (-10%) near the eastern limb, reached a peak value of -23% close to the central meridian, became zero around 40 deg W and ended as positive (+7 deg) near the western limb of the sun. Drift scans through the active region indicate that the leading spot, with negative magnetic polarity, was the dominant source of radio emission beyond 40 deg W longitude. This result leads us to conclude that the dominant negative polarity emission from the leading spot was reversed due to transverse propagation through the coronal magnetic fields in a region of moderate to weak coupling. The peaking of the polarization near central meridian can be accounted for by quasi-longitudinal propagation conditions over the leading spot with dominant emission.

Document Details

Document Type
Technical Report
Publication Date
May 01, 1977
Accession Number
ADA042849

Entities

People

  • Michaēl D. Papagiannēs
  • Ronald M. Straka

Organizations

  • Boston University

Tags

DTIC Thesaurus Topics

  • Circular Polarization
  • Couplings
  • Depolarization
  • Emission
  • Longitude
  • Magnetic Fields
  • Observation
  • Peak Values
  • Polarity
  • Polarization
  • Transverse

Readers

  • Mathematics or Statistics
  • Solar Physics
  • Space/Atmospheric Physics.