Atmosphere above a large solar pore

Eclipse on the Coral Sea: Cycle 24 Ascending

物理学;天文学

Sobotka, M.^1 ; Vanda, M.^1,2 ; Jurák, J.^1 ; Heinzel, P.^1 ; Moro, D. Del^3

Astronomical Institute, Academy of Sciences of the Czech Republic (V.v.i.), Friova 298, CZ-25165 Ondejov, Czech Republic^1

Charles University in Prague, Faculty of Mathematics and Physics, Astronomical Institute, V Holeovikách 2, CZ-18000 Prague 8, Czech Republic^2

Department of Physics, University of Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Roma, Italy^3

关键词: Acoustic power;    Chromospheric oscillations;    Doppler signals;    Dynamical properties;    Filamentary structures;    Long time series;    Solar telescope;    Spectral scans;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/440/1/012049/pdf
DOI  :  10.1088/1742-6596/440/1/012049

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

A large solar pore with a granular light bridge was observed on October 15, 2008 with the IBIS spectrometer at the Dunn Solar Telescope and a 69-min long time series of spectral scans in the lines Ca II 854.2 nm and Fe I 617.3 nm was obtained. The intensity and Doppler signals in the Ca II line were separated. This line samples the middle chromosphere in the core and the middle photosphere in the wings. Although no indication of a penumbra is seen in the photosphere, an extended filamentary structure, both in intensity and Doppler signals, is observed in the Ca II line core. An analysis of morphological and dynamical properties of the structure shows a close similarity to a superpenumbra of a sunspot with developed penumbra. A special attention is paid to the light bridge, which is the brightest feature in the pore seen in the Ca II line centre and shows an enhanced power of chromospheric oscillations at 3-5 mHz. Although the acoustic power flux in the light bridge is five times higher than in the "quiet" chromosphere, it cannot explain the observed brightness.