Evidence for non-potential magnetic fields in the quiet Sun

A comparison of BBSO H centerline filtergrams and videomagnetograms was made to investigate the existence of non- potential magnetic fields in the quiet Sun near magnetic network. We use the fibril structure in the H images as a proxy for the horizontal chromospheric magnetic field which we compare with the horizontal field obtained by potential extrapolation of the observed, line-of-sight photospheric field. The quiet-Sun field was found to be consistently and significantly non-potential in each of the three fields of view studied. A transient extreme ultraviolet (EUV) brightening, known as a blinker, occurred during the observations of a region where the field is highly non-potential, suggesting a connection between magnetic reconnection and non-potentiality.