A study of hydrogen density in emerging flux loops from a coordinated trace and Canary Islands observation campaign

During an international ground-based campaign in Canaries coordinated with Space instruments (TRACE, Yohkoh) we have observed an active region on September 10, 1998 with high spatial and temporal resolution. New emerging flux has been observed in magnetograms of the GCT, Tenerife and the SVST, LaPalma. The arch-filament systems are well developed in H alpha (VTT/DPSM, SVST) The multi-wavelength observations (SXT/Yohkoh, TRACE) allow us to analyse the behaviour of 3D loops visible in transition region and coronal temperatures. We discuss on different physical quantities: i.e temperature, hydrogen column density. The arch filament systems (AFS) correspond to low emission regions observed in wavelengths 171 Angstrom and 195 A due to absorption by hydrogen and helium in the cool prominence plasma. The emitting plasma around and above the AFS is at a measurably higher temperature than the large extended loops.