Inference of the magnetic field in spicules from spectropolarimetry of He I D
THEMIS. C/ Vía Láctea s/n, 38200 La Laguna, Tenerife, Spain e-mail: email@example.com
2 High Altitude Observatory, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000, USA
Accepted: 28 January 2005
We present observations of spicules in the D3 line with full-Stokes spectropolarimetry, which were done with the Advanced Stokes Polarimeter at the Dunn Solar Telescope of the Sacramento Peak Observatory. The line profiles appear to be significantly broadened by non-thermal processes, which we interpret using the hypothesis of a distribution of velocities inside the spicule. The possibility of inferring the magnetic field in those conditions is tested on synthetic data, and the results are generalized to the interpretation of the observed data. We conclude that the magnetic field is aligned with the visible structure of the spicule, with strengths above in some cases (for heights between 3000 and above the photosphere).
Key words: Sun: chromosphere / Sun: magnetic fields
© ESO, 2005