Center-to-limb-variation of the G-band lines at 430.5 nm
Kiepenheuer–Institut für Sonnenphysik, Schöneckstr. 6, 79104 Freiburg, Germany
Corresponding author: K. Langhans, firstname.lastname@example.org
Accepted: 8 November 2001
We measure the center-to-limb-variation of the CH lines in the wavelength range from 430.40 to 430.61 nm (G-band) for both quiet sun and for the cooler atmophere of sunspot umbrae at different heliographic positions. The limb effect of the CH lines is about 650 ms-1 at with a slope similar to weak Fe lines. We investigate the behaviour of the CH abundance in the range of optical depth ( to ) that is accessible by center-to-limb observations. The CH abundance decreases with height in accordance with recent numerical models.
Key words: Sun: atmosphere, photosphere
© ESO, 2002