The procedure for proposal preparation in the Data Flow system will differ from the current procedure in particular by the introduction of a Phase II proposal preparation. In Phase I, proposals are submitted electronically to ESO which forwards them to the Observing Program Committee (OPC). After the OPC selection has taken place, Phase II preparation is mandatory for service observing mode and is based on Template forms which allow to program a finite set of standard instrument modes and configurations. Feasibility checks of the proposals will be performed by the User Support Group and will include instrument configuration control, exposure time control using the ETCs. The use of Templates and generic Templates will be mandatory in classical observing mode unless it does not allow to achieve the scientific aims of the observing program. Generic Templates will offer a wide variety of configurations and will therefore not be suited for pipeline processing.
Observation preparation tools will be available during Phase I and Phase II. There will be generic systems like finding chart generators or guide star selection systems, and instrument related tools like exposure time calculators. Access to these tools will be supported over the World Wide Web only since it allows users to access easily the latest versions of software while facilitating the distribution and maintenance for the observatory. During prototype development Phase II tools will be developed both with the VLT Panel Editor and Web based technologies.
For each exposure time calculator a database of instrument description files and characteristic data will be maintained by a Data Flow Instrument Responsible located in Garching. A generic framework for the development of the exposure time calculators is being developed in the DMD. The driving design goal of this framework is to minimize the effort to create exposure time calculators for new instruments, while providing a common framework for all ETCs developed for the DFS.
Target information is also provided in Phase II and the Template sequences are defined within Observation Blocks. At the end of Phase II, Observation Blocks parameters have been defined and are submitted to the Observation Block Repository. The interface between P2PP and the VCS is described in [5].