Unlike current instruments, CTA will be operated as a proposal-driven open observatory. Observations will be carried out by observatory operators, then the data will be calibrated, reduced and, together with analysis tools, made available to the principle investigator in FITS data format. After a proprietary period, data will be made openly available through the CTA data archive.
The modes of user access to CTA will be:
- The Guest Observer (GO) Programme – by which users can obtain access to proprietary observation time, submitting proposals in response to Announcements of Opportunity (AOs).
- The Key Science Projects (KSPs) – are large programmes that ensure that some of the key science issues for CTA are addressed in a coherent fashion, with a well-defined strategy.
- Director’s Discretionary Time (DDT) – a small fraction of observation time may be reserved for, e.g., unanticipated targets of opportunity, or outstanding proposals from non-member countries.
- Archive Access – under which all CTA gamma-ray data will be openly available, after a proprietary period.
Beyond astronomy and astrophysics, anticipated user communities include cosmology, particle physics and plasma physics. During the first phase of operation, observation time will be split between guest observer time and KSPs, such as large-scale surveys aimed at providing legacy data sets.