Detalles de publicación
PP 010071
Interpretation of HINODE SOT/SP asymmetric Stokes profiles observed in quiet Sun network and internetwork
(1) ESA/ESTEC, (2) Universita di Roma Tor Vergata, and (3) IAC
Stokes profiles emerging from the magnetized solar photosphere and observed by SOT/SP aboard the HINODE
satellite present a variety of complex shapes. These are indicative of unresolved magnetic structures that have been
overlooked in the inversion analyses performed so far. Here we present the first interpretation of the Stokes profile
asymmetries measured in the Fe i 630 nm lines by SOT/SP, in both quiet Sun internetwork (IN) and network regions.
The inversion is carried out under the hypothesis of MIcro-Structured Magnetized Atmosphere (MISMA),
where the unresolved structure is assumed to be optically thin. We analyze a 29.52'' ×31.70'' subfield carefully selected
to be representative of the properties of a 302'' × 162'' quiet Sun field-of-view at disk center.
The inversion code is able to reproduce the observed asymmetries in a very satisfactory way, including the 35 %
of inverted profiles presenting large asymmetries. The inversion code interprets 25 % of inverted profiles as emerging
from pixels in which both positive and negative polarities coexist. These pixels are located either in frontiers between
opposite polarity patches or in very quiet regions. kG field strengths are found at the base of the photosphere in both
network and IN; in the case of the latter, both kG fields and hG fields are admixed. When considering the magnetic
properties at the mid photosphere most kG fields are gone, and the statistics is dominated by hG fields. According to
the magnetic filling factors derived from the inversion, we constrain the magnetic field of only 4.5 % of the analyzed
photosphere (and this percentage reduces to 1.3 % when referred to all pixels, including those with low polarization
not analyzed). The rest of the plasma is consistent with the presence of weak fields not contributing to the detected
polarization signals. The average flux densities derived in the full subfield and in IN regions are higher than the ones
derived from the same dataset by Milne-Eddington inversion.
The existence of large asymmetries in HINODE SOT/SP polarization profiles is uncovered. These are
not negligible in quiet Sun data. The MISMA inversion code reproduces them in a satisfactory way, and provides a
statistical description of the magnetized IN and network which partly differs and complements the results obtained so
far. From this it follows the importance of having a complete interpretation of the line profile shapes.
satellite present a variety of complex shapes. These are indicative of unresolved magnetic structures that have been
overlooked in the inversion analyses performed so far. Here we present the first interpretation of the Stokes profile
asymmetries measured in the Fe i 630 nm lines by SOT/SP, in both quiet Sun internetwork (IN) and network regions.
The inversion is carried out under the hypothesis of MIcro-Structured Magnetized Atmosphere (MISMA),
where the unresolved structure is assumed to be optically thin. We analyze a 29.52'' ×31.70'' subfield carefully selected
to be representative of the properties of a 302'' × 162'' quiet Sun field-of-view at disk center.
The inversion code is able to reproduce the observed asymmetries in a very satisfactory way, including the 35 %
of inverted profiles presenting large asymmetries. The inversion code interprets 25 % of inverted profiles as emerging
from pixels in which both positive and negative polarities coexist. These pixels are located either in frontiers between
opposite polarity patches or in very quiet regions. kG field strengths are found at the base of the photosphere in both
network and IN; in the case of the latter, both kG fields and hG fields are admixed. When considering the magnetic
properties at the mid photosphere most kG fields are gone, and the statistics is dominated by hG fields. According to
the magnetic filling factors derived from the inversion, we constrain the magnetic field of only 4.5 % of the analyzed
photosphere (and this percentage reduces to 1.3 % when referred to all pixels, including those with low polarization
not analyzed). The rest of the plasma is consistent with the presence of weak fields not contributing to the detected
polarization signals. The average flux densities derived in the full subfield and in IN regions are higher than the ones
derived from the same dataset by Milne-Eddington inversion.
The existence of large asymmetries in HINODE SOT/SP polarization profiles is uncovered. These are
not negligible in quiet Sun data. The MISMA inversion code reproduces them in a satisfactory way, and provides a
statistical description of the magnetized IN and network which partly differs and complements the results obtained so
far. From this it follows the importance of having a complete interpretation of the line profile shapes.