EDP Sciences
Free access
Volume 436, Number 2, June III 2005
Page(s) L27 - L30
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:200500114

A&A 436, L27-L30 (2005)
DOI: 10.1051/0004-6361:200500114


Magnetic flux in the internetwork quiet Sun

E. V. Khomenko1, 2, M. J. Martínez González1, M. Collados1, A. Vögler3, S. K. Solanki3, B. Ruiz Cobo1 and C. Beck4

1  Instituto de Astrofísica de Canarias, 38205 C/ vía Láctea, s/n, Tenerife, Spain
2  Main Astronomical Observatory, NAS, 03680 Kyiv, Zabolotnogo Str. 27, Ukraine
    e-mail: khomenko@iac.es
3  Max-Planck-Institut für Sonnensystemforschung, 37191 Katlenburg-Lindau, Germany

4  Kiepenheuer-Institut für Sonnenphysik, 79104 Freiburg, Germany

(Received 1 March 2005 / Accepted 26 April 2005 )

We report a direct comparison of the amplitudes of Stokes spectra of the Fe I 630 nm and 1.56 $\mu$m lines produced by realistic MHD simulations with simultaneous observations in the same spectral regions. The Stokes spectra were synthesized in snapshots with a mixed polarity magnetic field having a spatially averaged strength, $\langle B \rangle$, between 10 and 30 G. The distribution of Stokes V amplitudes depends sensitively on $\langle B \rangle$. A quiet inter-network region was observed at the German VTT simultaneously with TIP (1.56 $\mu$m) and POLIS (630 nm). We find that the Stokes V amplitudes of both infrared and visible observations are best reproduced by the simulation snapshot with $\langle B \rangle = 20$ G. In observations with 1 resolution, up to 2/3 of the magnetic flux can remain undetected.

Key words: Sun: MHD -- Sun: magnetic fields -- Sun: infrared -- Sun: polarization

© ESO 2005