Photospheric Hanle diagnostic of weak magnetic dipoles in stars
Abstract
Aims: We propose and explore a new diagnostic technique based upon the linear polarization emitted in Hanle-sensitive lines in disk-integrated stars where a dipolar magnetic field breaks the rotational symmetry of the resonance scattering polarization
Methods: A star with a simple dipolar field and a 1-0 spectral line were used to compute polarization amplitudes and angles.
Results: Predicted amplitudes are low but within reach of present instruments
Conclusions: A new application of the Hanle effect is proposed and analyzed as a tool that allows measuring of some of the weakest stellar magnetic fields.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 2011
- DOI:
- 10.1051/0004-6361/201015388
- arXiv:
- arXiv:1011.6288
- Bibcode:
- 2011A&A...527A.120L
- Keywords:
-
- techniques: polarimetric;
- techniques: spectroscopic;
- methods: observational;
- stars: magnetic field;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 6 pages, 3 figures. Accepted for publication in A&