Solar convection and oscillation interaction
Hanslmeier A.1, Kucera A.2, Rybak J.2,
Wöhl H.3, Gömöry P.1,2
1 IGAM/Kanzelhoehe Observatory, Institute of Physics, Universiteat Graz,
Universiteatsplatz 5, A-8010 Graz, Austria
2 Astronomical Institute of the Slovak Academy of Sciences,
SK-05960 Tatranská Lomnica, Slovakia
2 Kiepenheuer-Institute fur Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg, Germany
Abstract:
In this paper we investigate bisectors of solar photospheric lines. The bisectors reflect vertical
velocity gradients over the height of line formation and therefore reveal important information
about the dynamics in these layers. Their shape and shift is influenced by (a) convective motions,
(b) oscillatory motions that can act differently at different photospheric heights. The bisectors
are selected from different locations that show mainly a granular evolution or an intergranular
evolution. Two selection criteria were applied: continuum intensity (enhanced for granular bisectors,
reduced for intergranular bisectors), and full width at half maximum values (enhanced for intergranular
bisectors). The results demonstrate how oscillatory motions influence the bisectors as a whole. In
the example given a smaller amplitude of oscillations over intergranular areas is indicated.