| Presenter: | Reza Rezaei |
| Affiliation: | Kiepenheuer-Institut für Sonnenphysik |
| Title: | Temporal evolution of magnetic elements |
| Authors: | R. Rezaei, R. Schlichenmaier, W. Schmidt, and C. Beck |
| Form: | talk |
| Abstract: | We study the structure and evolution of the magnetic field of the quiet Sun by investigating weak spectro-polarimetric signals. To this end, we observed a quiet region close to the disk center with the German VTT in Tenerife, July 07, 2006. We recorded 38 scans of the same area. Each scan was 8 arcsec wide and recorded within about 100 sec. The POlarimetric Littrow Spectrograph (POLIS) was used to simultaneously observe full Stokes profiles of the neutral iron lines at 630.15 and 630.25\,nm, the Stokes $I$ profile of the Ca~{\sc{ii}}~H line at 396.8\,nm, and a continuum speckle channel at 500\,nm. In this way, we gathered magnetic field information at photospheric level, chromospheric emission, and high spatial resolution continuum images. We present data in which we witness cancellation of two small-scale opposite-polarity magnetic fluxes, followed by an enhanced chromospheric emission. We trace the propagation of the released energy from the photosphere to the chromosphere. The cancellation site was the vertex of a few intergranular lanes. The Stokes $V$ profiles at the neutral line had abnormal shapes through the time-series. The two opposite-polarity patches gradually became smaller and, within a quarter of an hour, the smaller one completely disappeared. The larger patch also diminished significantly. Our results indicate that the time-scale of the evolution of the polarization signal is significantly smaller than the granular time-scale, and may be even shorter than our temporal cadence. |
| Session: | 3. Nature of solar magnetic fields as revealed by polarimetry |
| Presentation date: | Tuesday 18th September |
| Presentation time: | 14:00:00 |