Access strategy and open access

Observations made by CTA are expected to serve a user community of at least 1000 people. Therefore, CTA must deal efficiently with a large number of internal and external proposals for the observation which is expected to be oversubscribed by a large factor. CTA plans to follow the practice of other major observatories and will announce calls for proposals at regular intervals. These proposals will be peer-reviewed by a group of international experts that will change on a regular basis. Different classes of proposals (targeted, surveys, coordinated multi-wavelength campaigns, time-critical, target of opportunity, and regular programmes) are foreseen. Depending on the science under investigation, sub-array operation may be required and each site can run several different observation programmes concurrently. The Czech node will be able to serve as a local contact when needed. It shall be able to efficiently distribute the calls among the national institutions, to help the external proponents with formal and informal contacts with relevant scientists abroad. The theoreticians and astrophysicists all around the world will not only submit their proposals but they will also follow published results and papers from the CTA core programme.

User access and workflow is planned to be organized as follows: the proposals are evaluated, prioritized and selected by the science operation centre, then the operation centre schedules and executes the operation and finally the data centre reduces and distributes the data products to the user. All centres shall stay in contact during the procedure to efficiently react and optimize the scientific output of the observation.

The observational time will be divided between the core CTA program (surveys, etc.) and open access where anybody from a country participating in the infrastructure can apply for observational time. The ratio between the time allocated to the core program and to the open access will evolve in time and shall guarantee reward to the major institutions that helped to build the infrastructure at the beginning. At the same time the policy will allow substantial time for any other scientist via open access when he/she submits a really excellent proposal. After several years of operation the open access time will reach ca. 50 percent. The detailed distribution of the observational time and CTA data between the open access and core science programmes is being intensively discussed. Several preliminary documents are already prepared. Schemes for scientific proposals and their evaluation are being prepared as well. The size of the Czech community that will be able to submit reasonable proposal to open access is about 40 people - most of them will participate also in the guaranteed core program. The size of the international community already amounts to 1400 people and is still growing.