Spectroscopy of solar prominences simultaneously from space and ground Spectroscopy of solar prominences simultaneously from space and ground Stellmacher, G. et al. 2003, Sol. Phys. 217, 133. S. Kamio 2004.04.12 Solar Seminar

Prominence Co-existing (unresolved) hot and cool plasma Higher charged ions (O IV, N V, S V, …) Neutral or singly charged ions (H I, He I, Ca II, …) (i) Cold threads surrounded by hot transition layer (ii) Isothermal threads of different temperatures

Instruments VTT/Tenerife (Vacuum Tower Telescope) Filter image: Hβ4862Å, Ca II 8542Å GCT/Tenerife (Gregory Coude Telescope) Spectrum: Ca II 8542Å, He I 10830Å SUMER/SOHO Cool lines(N I, C I, Si I), Lyman lines, Hot lines(O IV, S V, N V, …) TRACE Lyman α, 1600Å, and 171Å

Observation Prominences above the limb E/70N E/42N 1600Å 171Å Lymanα SUMER slit is indicated 1600Å 171Å Lymanα

He I 10830Å triplet Total optical thickness (τ0) can be derived from red/blue component ratio 1Å blue red components He I spectrum on the limb (by courtesy of I. Tohmura)

Excitation temperature Tex was estimated from observed intensity andτ Tex=3750K (mean) 4100K (peak for E/42N) 3850K (peak for E/70N)

Line width Estimated kinetic temperature and non-thermal broadening Brighter prominence (E/42N) is cooler T Vnth T(K) V(km/s) E/70N 8000-9500 3-6 E/42N 7500-9000 <7

Lyman series Oscillator strength versus line width τ>100 for prominence plasma (optically thick) Lyman lines may be emitted from outer part of prominence 19  k  5

Spatial distribution Hot lines (2x105K) S V, O V, … Cool lines (104K) Fe II, Si II, … Difficult to determine prominence models

Temperature and width E/70N E/42N Line width increases with formation temperature Large non-thermal velocity of E/70N is due to low density and magnetic field?

Summary 2 prominences were observed in different temperature lines. Optical thickness is derived from He I 10830Å red/blue ratio. Lyman lines may be emitted from outer part of prominence. Spatial distribution in hot and cool lines are different. Line width increases with formation temperature

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