Speaker
Hiva Pazira
(Stockholm University, ISP)
Description
The strongest line in the IR oxygen triplet is at 777.2 nm. Observations at this
wavelength with SST/CRISP reveal chromospheric features outside the solar limb.
Therefore, this line provides a new way to diagnose the chromosphere among the few
that can be observed with ground based telescopes. We conducted series of
simulations to understand what processes are in important in the formation of this
line and which chromospheric properties it samples. We used the RH code in spherical
geometry mode and the FAL model as atmospheric model. So far our results have shown
that the morphology of the O I 777.2 emission is set by variations of the line
opacity and not of the source function. The lower excited state of 777.2 nm is the
higher level of the 135.6 nm line which is observable with IRIS. Our next goal is to
combine observations with SST and IRIS, and simulations to asses how both oxygen
lines can be used as diagnostics in the chromosphere.
Primary author
Hiva Pazira
(Stockholm University, ISP)
