Comparison of model calculations and photometric observations of bright magnetic regions

Since 1981, several attempts to build series of semiempirical models designed to represent, in addition to the quiet Sun, the various types of magnetic regions across the solar disk (network, faculae and sunspots), have followed one another. Here we test the capability of those calculated by Fontenla et al. ([CITE]) to reproduce different experimental data, comparing the computed spectra with the observations made by the PSPT of the Rome Observatory. In particular, we study the average center-limb variation of the network and facular contrast. In this way, we are able to single out the models best reproducing the different photospheric structures operationally identified by the PSPT observations and data analysis. We show also that it would be possible, with slight modifications of the models, to further improve the agreement with the experimental data.

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