Accession Number : ADA185432
Title : The Appearance and Disappearance of Magnetic Flux on the Quiet Sun.
Descriptive Note : Final rept. 1 Oct 81-31 Dec 86,
Corporate Author : CALIFORNIA INST OF TECH PASADENA SOLAR ASTRONOMY GROUP
Personal Author(s) : Zirin, Harold ; Martin, Sara F
PDF Url : ADA185432
Report Date : Jul 1987
Pagination or Media Count : 19
Abstract : This project yielded the following significant new discoveries and findings about solar magnetic fields: The majority of magnetic flux on the sun is observed to disappear when magnetic fields of one polarity migrate into or develop in juxtaposition with fields of opposite polarity. The cancellation of magnetic fields can be interpreted as: (a) submergence (b) reconnection or (c) dissipation (annihilation) of magnetic fields. Large-scale filaments are observed to form in the chromosphere immediately above the boundaries between areas of network magnetic field of opposite polarity where network cancellation occurs. Small-scale filaments develop in association with small-scale cancelling magnetic fields at the rate of hundreds per day. Magnetic fields associated with large-scale solar convection cells, known as intranetwork magnetic fields, can be detected everywhere on the visible disk of the sun by using the videomagnetograph to integrate successive, 1/15 sec. magnetic field images for intervals of 1 to 10 minutes. The intranetwork field appear to be a few seconds of arc in diameter, and have field strengths of the order of a few Gauss to tens of Gauss. The intranetwork fields appear to originate at the centers of supergranules and flow to the boundaries of the cells in approximately radial patterns.
Descriptors : *SOLAR ACTIVITY, *MAGNETIC FIELDS, CHROMOSPHERE, TIME STUDIES, CONVECTION, SOLAR FLARES, FORECASTING
Subject Categories : Astrophysics
Distribution Statement : APPROVED FOR PUBLIC RELEASE