Bibcode
Centeno, R.; Trujilo-Bueno, J.; Uitenbroek, H.; Collados, M.
Referencia bibliográfica
Solar Polarization 5: In Honor of Jan Stenflo ASP Conference Series, Vol. 405, proceedings of the conference held 17-21 September, 2007 at Centro Stefano Franscini--Monte Veritá, Ascona, Switzerland. Edited by Svetlana V. Berdyugina, K. N. Nagendra, and Renzo Ramelli. San Francisco: Astronomical Society of the Pacific, 2009., p.297
Advertised on:
6
2009
Número de citas
5
Número de citas referidas
4
Descripción
One of the most useful spectral windows for spectropolarimetric
investigations of the solar chromosphere is the one provided by the
spectral lines of the He I 10830 Å multiplet, whose polarization
signals are sensitive to the Hanle and Zeeman effects. However, in order
to be able to carry out reliable diagnostics of the dynamic and magnetic
properties of the solar outer atmosphere it is crucial to have a good
physical understanding of the sensitivity of the observed spectral line
radiation to the various competing triggering mechanisms. Here we report
a series of on-disk and off-the-limb non-LTE calculations of the 10830
Å absorption and emission profiles, focusing our investigation on
their sensitivity to the EUV coronal irradiation and the model
atmosphere used in the calculations. We show in what respects the
on-disk case sensitivity of the polarization signals induced by the
Zeeman effect to the EUV coronal irradiance, and investigate whether or
not inversions based on the Milne-Eddington model are reliable.
Concerning the off-the-limb case we demonstrate that the intensity ratio
of the blue to the red components of the He I 10830 Å multiplet is
a sensitive function of the amount of EUV coronal illumination.
Therefore, measurements of this observable as a function of the distance
to the limb and its confrontation with radiative transfer modeling might
give us valuable information on the physical properties of the solar
atmosphere and on the amount of EUV radiation penetrating the
chromosphere from above.