Coma Parameters

The commission discussed the confusion that arises when researchers try to compare water production rates reported by different investigators due to the use of different models and different parameters for the models. It was noted that the problem is more widespread than just indices for release of water, involving a lack of a standard way of reporting release of dust and also the lack of any standard for determining the nuclear magnitude of a comet. After a proposal to create a special working group, it was decided that the Working Group on Comets, augmented as seen fit by the chairman of the working group, should be charged with addressing this problem and the commission passed, unopposed, the following resolution as a charge to the working group:

IAU Commission 15, noting the great confusion that arises when comparing molecular production rates from various papers in the refereed literature and noting that much of this confusion is due to the wide range of models and parameters used therein to interpret the fluxes from emission features, resolves that the Working Group on Comets should appoint a subgroup charged with proposing a standard set of parameters for deducing a water release index. This group is charged with considering both the physical correctness of the parameters and the ease of application by astronomers in all situations. The working group should also consider whether other parameters, such as nuclear magnitudes, indices of dust release, and indices of gas/dust ratio, should similarly be standardized. This group will report back to Commission 15 in time to consider resolutions for adoption at the 24th General Assembly.