PESSTO Survey Strategy

As the ESO approved time was stretched out over 5 years, we must either reduce the density of our observing runs (and still cover 12 months of every year), or reduce the annual survey period and keep the cadence and spectroscopic density coverage the same. The Survey Director recommends that the we reduce the annual survey period to approximately 9 months (actually 9 lunations) and schedule 10N per lunation broken into three runs of 4N, 3N and 3N.

In each calendar year PESSTO runs 1 Jan - 31 May and 1 Sept - 31 Dec i.e. it skips the three months June - August.



Overall, the main consideration has to be a direct coordination with the two southern surveys (given the uncertain futures of PTF and PS1 beyond 2012-2013) and optimising the number of likely clear nights together with young target selection. Hence the suggestion of 9 months (removing June - August).

In each of 9 lunations the following observing strategy, where one "Run" consists of three separate sub-runs :

Example of the three sub-runs during a lunation (Mar/Apr 2012 taken as an example) - see here for higher resolution pdf version : Lunation-Strategy.pdf

Observing management strategy:

Clearly, providing coverage with experienced observers for 90 nights per year is a significant challenge. This requires the commitment of institutions to provide the manpower to cover the observing runs and data reduction. We are proposing the following strategy.

Target alert and OB preparation

The observing team are responsible for coordination with the Target and Alert Team to define and prepare the night plan and the instrument OBs. We will run the observing time in Queue mode fashion, with the OBs normally being defined XX days before each run starts. However we want to ensure that rapid response can occur and we will instigate our own ToO mode - targets can be supplied by the Target and Alert Team directly to the observers and can request immediate observation. e.g. if surveys are producing targets rapidly enough that fast transients can be identified on the same night, then we will allow our own ToO type of over-ride.

Data reduction strategy:

Specific requirements and responsibilities :

outstanding questions on data reduction strategy

NTT pipeline