Abstract
We present high sensitivity H91α and 3.5 cm radio continuum observations toward the planetary nebula NGC 3242. The electron temperature determined assuming local thermodynamic equilibrium is consistent within ∼ 10% with that derived from optical lines and the Balmer discontinuity. The line emission and the continuum emission have a very similar spatial distribution, suggesting that at this wavelength there is no other continuum process present in a significant manner. In particular, we conclude that emission from spinning dust is not important at this wavelength. In this radio recombination line the nebula presents a radial velocity structure consistent with that obtained from observations of optical lines.
