The Gemini Observatory International Time Allocation Committee Process

The Gemini Observatory, a program of NSF's NOIRL ab, provides the astronomical communities in five participant countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country's contribution. In this paper we present an overview of the Gemini International Time Allocation Committee (ITAC) process whose purpose is to merge the successful proposals to create a single combined list of programs for execution on the two Gemini telescopes. The process of merging the successful programs from the National Time Allocation Committee (NTAC) is a complex process with many variables and considerations. This paper describes in detail the how-to (at the time of writing) of the main goals of the process, which are fairness and efficiency; ensuring that the telescopes are being used efficiently, and are never sitting idle when they could be executing a program of interest for one of the participants, as well as the users from the communities are not wasting time writing filler proposals that will never get executed. The success of this process is measured in executing the maximum number of highly ranked scientific programs within these constraints.