The 3.2–3.6 μ m emission features in comet P/Halley: spectral identifications and similarities

摘要: Ground-based spectroscopic observations of emission features near 3.3 μm in comet Halley are reported. At a resolution ∆λ/λ) = 0.012 the emissions consist several components between 3.2 and 3.6 μm, probably superpositions C—H group bands. The grains responsible for 3–20 thermal do not appear to be site band emitter, but either molecular or small particle is possible. shape differs from those interstellar emitting substances having strong longward This extra structure may due alkyl side-chains compounds characteristic low formation temperatures. Emission at 3.52 ±.02 could evidence oxygen containing molecules, possibly formaldehyde.