Observed IRIS Profiles of the h and k Doublet of Mg II and Comparison with Profiles from Quiescent Prominence NLTE Models

0461290 - ASÚ 2017 RIV NL eng J - Článek v odborném periodiku
Vial, J. C. - Pelouze, G. - Heinzel, Petr - Kleint, L. - Anzer, U.
Observed IRIS Profiles of the h and k Doublet of Mg II and Comparison with Profiles from Quiescent Prominence NLTE Models.
Solar Physics. Roč. 291, č. 1 (2016), s. 67-87. ISSN 0038-0938. E-ISSN 1573-093X
Institucionální podpora: RVO:67985815
Klíčová slova: Mg II lines * non-LTE diagnostic * Sun prominences
Kód oboru RIV: BN - Astronomie a nebeská mechanika, astrofyzika
Impakt faktor: 2.682, rok: 2016

We aim at comparing unique observations obtained in the Mg II h and k lines of a polar crown prominence with the radiative outputs from one-dimensional models built with non-local-thermodynamic equilibrium codes. We characterize the profiles obtained through thorough calibration procedures, with attention paid to the absolute values, full-width at half-maximum, and the ratio of k to h intensities. We also show that at the top of some structures, line-of-sight velocities of about 9 kms(-1) can be detected. We find a range of static, low-pressure, low-thickness, low-temperature models that could fit k or h observed values, but that cannot satisfy the low observed k/h ratio. We investigate whether these low values might be explained by the inclusion of horizontal flows in small-scale threads. These flows are also necessary in another class of models, where the pressure is kept low but thickness and temperature are increased up to the observed thickness and up to 15000 K.
Trvalý link: http://hdl.handle.net/11104/0260918