A Target-of-Opportunity (ToO) programme is one for which observations of a rare or transient event are required at short notice, and they can be justified by the unique scientific opportunity these observations represent.

PIs of ToO observations that can be anticipated at the semestral subsmision deadline for regular proposals, please refer to the latest announcement of opportunity. Triggering teams of allocated programmes, can submit their ToO requests using a phase-2 catalogue format, which ING will use to generate the observing blocks. The reduced observations will be available on the WEAVE Operational Repository.

For observations of unanticipated ToOs of high scientific impact, the ING Director should be contacted with a brief science case justifying the need for the urgency, and the observations requested. Phase-2 preparation is similar to ToO observations above.

Time-critical observations (at a certain time) and monitoring programmes (repeated observations over a period of time executed at a given cadence) are possible. For discussion on feasibility and instructions on how to proceed, please contact for details:

weave_open_time_supporting.iac.es

A filler proposal is one that it will be attempted under poor conditions, and hence, PIs of filler proposals should expect that their observations could be executed not necessarily in short time (proposal lifecycle is 3 years). These are the requirements for a filler proposal:

• It will be observed in conditions with OBSTEMP=XEFEG, equivalent to

  Seeing ≤3.0"
  Transparency ≥0.4
  Elevation: ≥25.0° (X≤2.4)
  Moon distance: Unconstrained
  Sky brightness: ≥17.7 V_mag/arcsec² (bright)

• LIFU mode only.

Community fibres (access to fibres not used in another observer or survey configuration) are likely to be offered (at least some of these, depending on demand) once the WEAVE observations are running smoothly.