Magnetic, basal, and radiative-equilibrium components in Mount Wilson Ca II H + K fluxes

Technical Report · Thu Jun 15 04:00:00 EDT 1989

OSTI ID:5428685

Schrijver, C J; Dobson, A K; Radick, R R

Mount Wilson Ca II H + K flux measurements of cool dwarf stars are analyzed comparing the fluxes with stellar Mg U H + K fluxes, variability amplitudes, rotation rates, and solar data. The authors conclude that the Mount Wilson Ca U H + K fluxes comprise three principal parts: (1) a photospheric contribution in the line wings, (2) a basal chromospheric component that appears to be unrelated to stellar magnetic activity and is therefore possibly nonmagnetic in origin, and (3) a chromospheric component that they associate with magnetically active regions and the (quiet and active) network. The basal chromosphere appears to cover the entire surface of magnetically inactive stars. The basal Ca II H + K flux density for solar-type stars equals the average emission observed in the center of solar supergranulation cells, where the magnetic flux density is small.

• Research Organization: Air Force Geophysics Lab., Hanscom AFB, MA (USA)
• OSTI ID: 5428685
• Report Number(s): AD-A-211736/4/XAB; AFGL-TR--89-0214
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALKALINE EARTH METALS
ATMOSPHERES
CALCIUM
DWARF STARS
ELEMENTS
EMISSION SPECTRA
FLUX DENSITY
MAGNETIC FIELDS
METALS
MOTION
ROTATION
SPECTRA
STARS
STELLAR ATMOSPHERES
STELLAR CHROMOSPHERES