Hillock and cloud model for faculae

Journal Article · Mon Dec 01 04:00:00 EST 1986 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/164786· OSTI ID:6513097

Schatten, K H; Mayr, H G; Omidvar, K; Maier, E

A hillock model is used here to explain facular contrasts, allowing faculae to emit more energy than the surrounding unmagnetized photosphere. For downflows, horizontal motions converge near the photosphere and many fibril flux tubes are drawn together to form a large dark area, the sunspot. For upflows, the motions diverge near the photosphere and fibril flux tubes are dispersed over a larger area associated with faculae. The upflows transport material and energy, resulting in hotter than normal temperatures, which in turn cause the gas to expand compared with its surroundings. Buoyancy thus causes a network of patchy hillocks, clouds, or geysers to form which allows the sun to reradiate the energy deficit associated with sunspots by locally increasing the effective surface area of the sun beyond that of a sphere. The consequences of this model for the physical form of the facular manifestation, the appearance of faculae from earth, and the energy balance in active regions are addressed. 34 references.

• Research Organization: NASA, Goddard Space Flight Center, Greenbelt, MD
• OSTI ID: 6513097
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 311; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
ATMOSPHERIC CIRCULATION
FACULAE
MAGNETIC FIELDS
MASS TRANSFER
MATHEMATICAL MODELS
PHOTOSPHERE
SOLAR ACTIVITY
SOLAR ATMOSPHERE
STARSPOTS
STELLAR ACTIVITY
SUNSPOTS