There are different schemes for proposals as indicated below:
- The standard call for proposals: Telescope time for GTC, WHT, INT, TNG, NOT, Mercator, and Liverpool on La Palma and Stella on Tenerife is allocated twice a year in periods of 6 months. Regular and large proposals are accepted according to the conditions described in the standard call for proposals every semester. Allocation periods run as follows:
| Semester | Telescope | Period |
|---|---|---|
|
Semesters A Due date: beginning of October. CAT meeting: end of November. |
Liverpool* WHT, INT, Stella GTC NOT, TNG, Mercator |
January – August* February – July March – August April – September |
|
Semesters B Due date: beginning of April. CAT meeting: end of May. |
Liverpool* WHT, INT, Stella GTC NOT, TNG, Mercator |
July – February* August – January September – February October – March |
*A two month overlap period is adopted at the start and end of each period, when proposals from both semesters may be observed, in order to reduce problems with under-filled observation queues.
- DDT. Up to a few per cent of the general observing time may be used for the IAC Director’s Discretionary Time (DDT) Proposals on GTC, WHT, INT, TNG, and NOT. See DDT GTC and DDT WHT, INT, NOT, TNG for further details on conditions and for application forms. DDT proposals can be submitted at any time.
- GTC. Approved DDT proposals can be executed in either visitor or queue mode according to the Principal Investigator’s requirement.
- WHT, INT, TNG, and NOT. The CAT DDT nights are known a priori for each semester. Interested applicants must submit their proposals asking for specific nights ideally 20 days (strict limit is 10 days) before the scheduled CAT DDT nights. DDT proposals are to be executed in visitor mode.
- INT, TNG, and NOT. DDT proposals are accepted for every night allocated as Service Time. Applicants must indicate in their proposal that they are applying for a DDT program.
- Service Time. A fraction of the general observing time is also offered in the form of Service time on WHT, INT, NOT, LT, and TNG. Service proposals can be submitted at any time (see next), and will be “active” for a period of 1 year.
- INT, NOT, TNG. The CAT service nights are known a priori for each semester. Interested applicants must submit their proposals asking for specific nights ideally 10 days before the scheduled CAT service nights. Service observations on the INT, NOT, and TNG will always be executed by the team of IAC support astronomers. For the three telescopes, you can find the list of approved CAT service proposals and the list of available CAT DDT and service nights.
- WHT. The service time is shared by all TACs. Service observations on the WHT are executed by ING staff. WHT service proposals can be submitted at any time.
- LT. Service mode on the LT (“LT reactive time”) is recently implemented within the CAT (semesters 2016A and 2016B). Observations run in queue mode and are executed by LT staff. No LT reactive time is available in 2017A.
- Other schemes. Other schemes for proposals are available, which result from various agreements between Institutions.