The ob tab

This tab defines the complete OB, by gathering all the information defined in previous tabs. One line is one OB. Only in this tab the PIs may introduce new lines (but not columns) for comments. In this case, the line should be placed in column A and should start with a hash #.

Code is the name of the OB. It will be used by the scheduler and telescope control system, so it should be defined as uniquely as possible. The drop-down menus should be used to fill the next 6 columns, by choosing the codes of the targets, instrument, telescope (“p_opt2” only) and environmental configurations defined in previous tabs. The same target can be observed in various configurations, and a separate line (=OB) is required for each combination. The columns calib_tgtcfg and calib_inscfg have been added to the spreadsheet since S18A. These refer to the standard star fields. “Default” calib_tgtcfg means that the standard star field is at the same coordinate as the main target, which is the case if the main target is located inside the SDSS coverage. In case no calibration is required, the field should be left blank, otherwise desired calibration field code needs to be chosen from the drop-down menu. The same conventions hold for the calib_inscfg column. In case of “default”, the same configuration as that of the main target is used and a 30s exposure will be taken. In case of narrow-band observations, setting calib_tgtcfg and calib_inscfg as “default” means using a spectrophotometric standard star provided by the observatory, as described above.

If one decides to split the dithering into two configurations, one should prepare separate OBs for each of them. The On-src Time and Total Time (in seconds) are automatically calculated for the chosen inscfg. These columns should not be edited. In Phase 2 the readout overheads need to be included in the OBs.

Finally, OBs can be prioritized by giving them appropriate numbers in the column Priority. The lower the number (the lowest is 1), the more important the OB is, and will most likely be executed earlier. Several or even all OBs may have the same Priority. Prioritizing may be useful in case of programs where more targets were defined in Phase 1 than are expected to be observed.

The table on the right summarizes the total on-source time that has been programmed (sum over all values of the On-src Time column), the total required time3.6 including on-source time, overhead time per frame, and overhead time required for the queue-mode operation, and compares it with the total time allocated by the TAC (automatically loaded from the proposal tab). From S21A, the allocated time includes all overhead time. If the total required time exceeds the allocated time, a warning message is shown in the red field to the right, but such a situation is allowed. These fields should not be modified.