%0 Journal Article %T The Na i and Sr ii Resonance Lines in Solar Prominences %+ Institut d'Astrophysique de Paris (IAP) %A Stellmacher, G. %A Wiehr, E. %< avec comité de lecture %J SOLAR PHYSICS %V 292 %8 2017 %D 2017 %Z 1705.02475 %Z 2017SoPh..292...83S %R 10.1007/s11207-017-1103-6 %K Prominences %K models %K Spectral line %K broadening %K Astrophysics - Solar and Stellar Astrophysics %Z Sciences of the Universe [physics]Journal articles %X We estimate the electron density, ne, and its spatial variation in quiescent prominences from the observed emission ratio of the resonance lines Na i 5890 Å (D2) and Sr ii 4078 Å. For a bright prominence (τ_{α}≈25) we obtain a mean ne≈2×10^{10} cm^{-3}; for a faint one (τ _{α }≈4) ne≈4×10^{10} cm^{-3} on two consecutive days with moderate internal fluctuation and no systematic variation with height above the solar limb. The thermal and non-thermal contributions to the line broadening, T_{kin} and V_{nth}, required to deduce ne from the emission ratio Na i/Sr ii cannot be unambiguously determined from observed widths of lines from atoms of different mass. The reduced widths, ΔλD0, of Sr ii 4078 Å show an excess over those from Na D2 and Hδ 4101 Å, assuming the same T_{kin} and V_{nth}. We attribute this excess broadening to higher non-thermal broadening induced by interaction of ions with the prominence magnetic field. This is suggested by the finding of higher macro-shifts of Sr ii 4078 Å as compared to those from Na D2. %G English %L insu-03747452 %U https://insu.hal.science/insu-03747452 %~ INSU %~ CNRS %~ IAP %~ SORBONNE-UNIVERSITE %~ SU-INF-2018 %~ SU-SCIENCES %~ SU-TI %~ ALLIANCE-SU