Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields

Details Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields

2008-11-04

arxiv.org/abs/0811.0512v1

Astrophys.J.701:L43-L46,2009

Astronomy and Astrophysics

Astrophysics

Scientific paper

10.1088/0004-637X/701/1/L43

For about a decade, spectro-polarimetry of HeI 10830 has been applied to the magnetic diagnostics of the solar chromosphere. This resonance line is very versatile, as it is visible both on disk and in off-limb structures, and it has a good sensitivity to both the weak-field Hanle effect and the strong-field Zeeman effect. Recent observations of an active-region filament showed that the linear polarization was dominated by the transverse Zeeman effect, with very little or no hint of scattering polarization. This is surprising, since the HeI levels should be significantly polarized in a conventional scattering scenario. To explain the observed level of atomic depolarization by collisional or radiative processes, one must invoke plasma densities larger by several orders of magnitude than currently known values for prominences. We show that such depolarization can be explained quite naturally by the presence of an unresolved, highly entangled magnetic field, which averages to give the ordered field inferred from spectro-polarimetric data, over the typical temporal and spatial scales of the observations. We present a modeling of the polarized HeI 10830 in this scenario, and discuss its implications for the magnetic diagnostics of prominences and spicules, and for the general study of unresolved magnetic field distributions in the solar atmosphere.

Affiliated with

Also associated with

No associations

Rating

Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polarimetric Diagnostics of Unresolved Chromospheric Magnetic Fields will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-184317