TEMPERATURES OF THE JOVIAN AURORAL-ZONE INFERRED FROM 2-MU-M H-2 QUADRUPOLE LINE OBSERVATIONS

We have observed 2-μm H2 quadropole lines, S1(0), S1(1), and S1(2), in the southern auroral zone of Jupiter. From the observed intensities, we derived a rotational temperature of 730°K plus 490°K and minus 200°K in the 1 to 0.01 μbar pressure range. We conclude that the derived rotational temperature should represent the local neutral kinetic temperature. Furthermore, we found that H2(ν = 1) population in the auroral zone is at least 500 times greater than the normal Boltzmann population, indicating that nonthermal emission is dominant for these lines. We also calculated both nonthermal and thermal intensities of the pure H2 rotational quadropole lines and found the opposite result-that the thermal emission dominates over the nonthermal emission-for those lines in the longer wavelength region (>5 μm). © 1990.