The scattering mean free path in the Uranian atmosphere

New measurements of the equivalent widths of the 4-0 S(0) and S(1) H"2 quadrupole lines in the Uranian spectrum have been obtained using high dispersion (4.12 Å/mm) image-tube spectrography. The measured equivalent widths are 62 +/- 19mÅ and 58 +/- 13 mÅ for the S(0) and S(1) lines, respectivel...
Ausführliche Beschreibung

New measurements of the equivalent widths of the 4-0 S(0) and S(1) H"2 quadrupole lines in the Uranian spectrum have been obtained using high dispersion (4.12 Å/mm) image-tube spectrography. The measured equivalent widths are 62 +/- 19mÅ and 58 +/- 13 mÅ for the S(0) and S(1) lines, respectively. Curve-of-growth analysis in terms of a reflecting layer model yields an H"2 column-density of 780"-"3"3"0^+^9^4^0km amagat and a temperature of 78"-"2"4^+^8^0^oK. Interpretation using a semi-infinite, homogeneous, isotropically scattering model for line formation yields a scattering mean free path at λ6400 Å of 550 +/- 250 km amagat. Quoted errors for both the H"2 column-density and the scattering mean free path include the effect of uncertainty in the choice of atmospheric temperature. The results are discussed in terms of current models for the Uranian atmosphere. Ausführliche Beschreibung