Observations of the forward scattering Hanle Effect the Ca I 4227 Å Line
Informazioni aggiuntive
Autori
Bianda M.,
Ramelli R.,
Anusha L.,
Stenflo J. O.,
Nagendra K.,
Holzreuter R.,
Sampoorna M.,
Frisch H.,
Smitha H.
Tipo
Articolo pubblicato in rivista scientifica
Anno
2011
Lingua
Inglese
Abstract
Chromospheric magnetic fields are notoriously difficult to measure. The chromospheric lines are broad, while the fields are producing a minuscule Zeeman-effect polarization. A promising diagnostic alternative is provided by the forward-scattering Hanle effect, which can be recorded in chromospheric lines such as the He i 10 830 Å and the Ca i 4227 Å lines. We present a set of spectropolarimetric observations of the full Stokes vector obtained near the center of the solar disk in the Ca i 4227 Å line with the ZIMPOL polarimeter at the IRSOL observatory. We detect a number of interesting forward-scattering Hanle effect signatures, which we model successfully using polarized radiative transfer. Here we focus on the observational aspects, while a separate companion paper deals with the theoretical modeling.
Rivista
Astronomy and Astrophysics
Volume
530
Pagina inizio
L13
Parole chiave
irsol-refereed-scientific-papers
