SIMBAD references

Emission lines in the eV and keV range by certain stellar candidates from their recent analysis invoke the question of their possible origin. The stars under consideration are 4U0614+091 (0.65, 0.86 and 1.31 keV), 2S 0918-549 (0.8 keV with width 55 eV), 4U 1543-624 (0.7 keV), 4U 1850 -087 (0.7 keV) and 4U 1820-30 (0.6 and 0.9 keV) and also the 0.6-keV excess emission in RX J170930.2-263927. Recently, it has been suggested that the resonance absorption at ∼ 0.7, 1.4, 2.1 and 2.8 keV in 1E1207-5209 and 0.35, 0.7 and 1.4 keV in RX J1856.5-3754 are due to harmonic surface vibrations in strange stars. We propose that these harmonic vibrations may also be responsible for emission lines in the above mentioned compact stellar candidates.