𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Center to limb variation of penumbral Stokes V profiles

✍ Scribed by M. Franz; R. Schlichenmaier

Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
191 KB
Volume
331
Category
Article
ISSN
0004-6337

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

We investigated the horizontal and the vertical component of the Evershed flow (EF). To this end, we computed average Stokes V profiles for various velocity classes in penumbrae at different heliocentric angles. Our results show that for blueshifted profiles an additional lobe with the same polarity as the spot is present in the blue side of the average Stokes V profile. The amplitude of the additional lobe grows with increasing blueshift and with increasing heliocentric angle. For small redshifts, the profiles show an additional lobe with the opposite polarity as the spot on the red side of the average Stokes V profile. Even at disk center, the original polarity of the average Stokes V profile is reversed for strong redshifts. The transition between the different types of Stokes V profiles is continuous and indicates that not only the vertical, but also the horizontal EF is a magnetized stream of plasma in a magnetic background field (Β© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

πŸ“œ SIMILAR VOLUMES

Center to limb variation of solar granul
Center to limb variation of solar granulation
✍ R. Jain; R. Muller πŸ“‚ Article πŸ“… 1989 πŸ› Springer 🌐 English βš– 518 KB

From high resolution white light photographs it is determined that the surface density of solar granulation decreases towards limb. A schematic model is proposed to interpret both decrease of surface density and size of granules in the upper photosphere.

On the center-to-limb variation of sunsp
On the center-to-limb variation of sunspot brightness
✍ W. Mattig πŸ“‚ Article πŸ“… 1969 πŸ› Springer 🌐 English βš– 232 KB

A preliminary analysis of recent measurements of the brightness ratio spot-photosphere of various authors leads to the result, that the limb-darkening of the umbra is considerably less than that of the photosphere. The small value of the center-to-limb variation implies a very small temperature grad

The center-to-limb variation of the phot
The center-to-limb variation of the photospheric wave spectrum
✍ M. Stix; H. WΓΆhl πŸ“‚ Article πŸ“… 1974 πŸ› Springer 🌐 English βš– 696 KB

Using photoelectric observations in the Fe 5576/~ line we obtained line-of-sight velocities at nine different positions on the solar disk, as functions of one horizontal co-ordinate and time. With the help of the Fast Fourier Transform algorithm we calculated two-dimensional power spectra (horizonta