English

Simultaneous visible and infrared spectro-polarimetry of a solar internetwork region

Astrophysics 2009-11-10 v1

Abstract

We present the first simultaneous infrared (IR) and visible spectro-polarimetric observations of a solar internetwork region. The Fe I lines at 6301.6 A, 6302.5 A, 15648 A, and 15652 A were observed, with a lag of only 1 min, using highly sensitive spectro-polarimeters operated in two different telescopes (VTT and THEMIS at the Observatorio del Teide). Some 30% of the observed region shows IR and visible Stokes V signals above noise. These polarization signals indicate the presence of kG magnetic field strengths (traced by the visible lines) co-existing with sub-kG fields (traced by the infrared lines). In addition, one quarter of the pixels with signal have visible and IR Stokes V profiles with opposite polarity. We estimate the probability density function of finding each longitudinal magnetic field strength in the region. It has a tail of kG field strengths that accounts for most of the (unsigned) magnetic flux of the region.

Keywords

Cite

@article{arxiv.astro-ph/0309727,
  title  = {Simultaneous visible and infrared spectro-polarimetry of a solar internetwork region},
  author = {J. Sanchez Almeida and I. Dominguez Cerdena and F. Kneer},
  journal= {arXiv preprint arXiv:astro-ph/0309727},
  year   = {2009}
}

Comments

ApJL, accepted