Overhead time of HSC Queue-mode observation

The overhead time of HSC queue-mode observations is divided into the following two items.

  1. Overhead time par object frame: 40 sec/frame

    This is the time needed between the exposures, including data transfer, moving the telescope to the next dithering position, and so on. Total time needed for integration, data readout and slewing (T1) is expressed as follows;

    T1 = (Exptime1 + 40 sec) * N1 + (Exptime2 + 40 sec) * N2 + ...

    Nx is the number of shots with Exptimex (sec) integration time.
  2. Overhead time of the queue-mode operation: 1.2 hours/night

    The average overhead time caused by focusing, filter-exchange, obtaining calibration frames (T2) is 1.2 hours per night for HSC queue observation. The available observation hours per night is 10.0 hours (yearly average). Therefore, every (10.0 - 1.2) = 8.8 hours of T1, we charge 1.2 hours as the overhead time to operate queue-mode observation.

    T2 = T1 / (10.0 hours -1.2 hours ) * 1.2 hours

Therefore, the total required time including all overhead time can be caluculated as follows. Please write this total required time as the request hours at "Observing Run" of your proposal.

The total required time = T1 + T2 ~ 1.137 * T1

© 2020 Subaru Telescope, NAOJ