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With the flexible scheduling used at the APEX telescope, several projects are scheduled at a time. Usually, a project is not finished within one observing session. The average project has to be observed during several nights, in order to optimize the telescope efficiency. In order to keep track of the status of a project, a proper progress monitoring is needed, to make sure that the amount and quality (i.e. signal-to-noise ratio) of the data is sufficient to reach the scientific goals of the project, and, on the other hand, not to overobserve one project on the cost of others. We have implemented two monitoring tools for this purpose.

1 TWiki Project Pages

The first monitoring tool implemented at APEX are TWiki pages. TWiki is a Wiki software used to create a web-based collaboration platform. While the APEX TWiki is mainly used for that purpose, it also serves as a tool to organize and monitor observing programs.

The initial version of the TWiki project pages are created upon project submission. In this stage the pages contain all information necessary to start the observations of this project, like source and line names, observing patterns, or special instructions for the APEX staff entered into the submission form by the PI.

During the submission two tables are created on these pages, one is supposed to contain information about the status of the observations, the other summarizes the already performed observations and provides links to observing log files created by the control system. After a first data verification and preliminary data reduction is done by the APEX astronomer (ideally still during the same observing night), these tables are filled out with all necessary information to indicate the current status of the project (see Fig. 3).

Upon completion of a project, these project pages are converted to standard HTML format and sent to the PI, together with the data and the observing log files.

Figure: The lower part of a typical TWiki project page used at APEX for progress monitoring. The two tables visible are created automatically, and filled out by the APEX staff during and after the observations.
\includegraphics[angle=0, width=15cm]{twiki2.eps}

2 Observing database

A second monitoring tool is the APEX observing database. This data base is a modified version of the pool observing database used successfully for several years now at the IRAM 30-m telescope[3].

Upon project submission, a database account with the project name is automatically created. The software also fills in details about target sources, instrumental requirements, and general project information. The instructions entered by the PI into the web submission form are also used to fill the corresponding database fields.

The APEX control system has direct access to this database. When a project with an existing database account is observed, information about target sources, observing pattern, scan numbers, and observing time are transmitted to the data base. This database therefore can also serve as a tool to follow the progress of a given project. Up to now, however, no data reduction tools have been implemented. As a result, while the total observing time can be tracked, it is not possible to verify the data quality using this database. Thus it is mainly used for scheduling purposes.

Michael Dumke, 19 May 2009. Article © SPIE