Dual Flows with Supersonic Velocities in the Sunspot Transition Region
Wilhelm, K.; Kjeldseth-Moe, O.; Brynildsen, N.; Maltby, P.
Norway, Germany
Abstract
Observations of sunspot transition region lines that deviate significantly from a Gaussian shape are presented. Attention is given to ``dual flows,'' a line profile phenomenon in which two distinct velocities are observed within the same spatial resolution element. In 5 out of 12 sunspots we observe dual flows. Several emission line profiles are well represented by two Gaussian line components, one with a subsonic and one with a supersonic line-of-sight velocity.