Thermal maps of sunspots and the quiet sun

Conference · Wed Jan 01 04:00:00 EST 1992 · American Astronomical Society, Bulletin; (United States)

OSTI ID:6654469

Livingston, W; Kopp, G; Gezari, D

We present images of sunspots, surrounding plage, quiet Sun, and the solar limb made at 4.8, 12.4, and 18 [mu]m. These are basically thermal maps, the infrared intensity being nearly linearly proportional to temperature at these wavelengths. We believe these to be the most detailed thermal images to date of the solar photosphere. Thermal structure within sunspot penumbrae and the surrounding plage is evident in several images, although umbrae appear homogeneous, at least down to the approximately 2'' diffraction limit of the telescope at 12 [mu]m. We find the temperature of penumbrae to be roughly 5% less than that of the quiet Sun, and umbrae to be about 25% less. Images of the quiet Sun show spatial thermal fluctuations of about 2% in patterns that change slowly with time. The measurements were made with the NSO's windowless, filled-aperture 1.6 m McMath-Pierce Solar Telescope, which fed the infrared image to a cryogenially-cooled 58 [times] 62 Si:Ge camera system built by D. Gezari.

• OSTI ID: 6654469
• Report Number(s): CONF-930189--
• Conference Information: Journal Name: American Astronomical Society, Bulletin; (United States) Journal Volume: 24:4
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
DATA
DIAGNOSTIC USES
EXPERIMENTAL DATA
IMAGES
INFORMATION
MAPPING
NUMERICAL DATA
PHOTOSPHERE
PLAGES
SOLAR ACTIVITY
SOLAR ATMOSPHERE
STARSPOTS
STELLAR ACTIVITY
SUNSPOTS
TELESCOPES
TEMPERATURE MEASUREMENT
USES