Molecular parentage of radical species in the comae of comets.

摘要

Understanding the chemical composition of comets is of great interest to the scientific community. In this work, an integral field unit (IFU) spectrograph is used to detect emissions of C2, C3, CH, CN, and NH2. The azimuthal average profile (line integral of the column density as a function of radial distance from the center of the nucleus) is simulated by the Haser model. The Haser model simulates the outgassing and photo-dissociate of molecular species in the coma. In this work, the lifetime of the parent molecule in the photo-dissociation chain is set as a free parameter. The best fit parent lifetimes for observations of comets 4P/Faye, 10P/Tempel 2, and C/2009 P1 Garradd are obtained. The results are compared to parent lifetimes cited in other studies. HCN as a likely dominant parent for CN is eliminated. Constraints on likely parent molecules for C3 and NH 2 are discussed.