Photospheric supergranular flows and magnetic flux emergence

A recent study carried out on high sensitivity SUNRISE/IMAX data has reported about the existence of areas of limited flux emergence in the quiet Sun. By exploiting an independent and longer (4 hours) data set acquired by HINODE/SOT, we further investigate these regions by analysing their spatial distribution and relation with the supergranular flow. Our findings, while confirming the presence of these calm areas, also show that the rate of emergence of small magnetic elements is largely suppressed at the locations where the divergence of the supergranular plasma flows is positive. This means that the dead calm areas previously reported in literature are not randomly distributed over the solar photosphere but they are linked to the supergranular cells themselves. These results are discussed in the framework of the recent literature.

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