A major IT maintenance will take place at ESO between Saturday, 20th April 2024 at 08:00 CEST and Sunday, 21st April 2024 at 24:00 CEST. From 08:00 CEST on Saturday all ESO IT services  could be subject to intermittent outages. You may thus encounter some difficulties using the p2 interface to edit your Observation Blocks, downloading data from the Science Archive or accessing our Help Portal at support.eso.org. We apologize for the inconvenience.

OB Execution Overheads

The time allocated to your program is total execution time, i.e., integration time + overheads. Therefore, the total execution time of the Observation Blocks (OBs) you submit should be less than or equal to the total time allocated, with the only possible exception of Target of Opportunity runs. The option of submitting OBs for an execution time exceeding the allocation and terminating the programme when the allocation time is exceeded is not currently supported in Service Mode.

To determine total execution time, please use the the Execution Time report function in the web-based p2.

To enable flexible scheduling in Service Mode the OB execution times must be below 1 hour. Long OBs are more difficult to schedule and execute within the specified constraints because of the unpredictable evolution of the observing conditions. For this reason, OBs taking more than one hour to execute are accepted by ESO only in exceptional cases and provided that a Phase 2 Waiver Request is submitted and approved. In such cases, ESO will consider the OB successfully executed if the constraints were fulfilled during the first hour of execution, even if conditions degrade after that time.

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