Call for proposals – Semester 2017A

The deadline for the submission of proposals for Spanish CAT night observing time for semester 2017A is Tuesday, 4 October 2016, at 17 h Canarian local time. The call for collaborative proposals between Spanish and Mexican astronomers at the GTC (Spanish/Mex Time, see below) is also open, with the same deadline.

  • We recall that every proposal within the Spanish CAT scheme must be led by a principal  investigator (PI) affiliated to a Spanish Institution. GTC Spanish/Mex proposals can have either a Spanish or Mexican PI, and must include co-Investigators (co-Is) from both communities (see below).
  • The start and end of the semester change with telescope as illustrated next:
    • WHT, INT, Mercator, Stella:   February – July.
    • NOT, TNG:   April – September.
    • GTC:   March – August.
    • Liverpool (LT):   January – August (a two-month overlap period is adopted at the start and end of each semester, when proposals from both semesters may be observed in order to reduce problems with under-filled observations queues).
  • Large programs are not accepted for GTC in semester 2017A. Large program proposals extending over two semesters (2017A and 2017B) are accepted for WHT and INT (see below for details). Large program proposals extending up to four semesters (2017A through 2018B) with TNG, NOT, LT, Mercator, and/or Stella can be submitted. See below.

Please, read carefully the following information and recommendations made for each telescope and for large programs. There are changes with respect to previous calls for proposals.


Detailed information about the feature of GTC for this semester can be found on the GTC call for proposals. Please note that:

  • OSIRIS and CIRCE are offered in this call. Canaricam is no longer offered.
  • In semester 2017A, no Large Programs are accepted. Large Programs will be offered starting in 2017B, once EMIR has been commissioned.
  • OSIRIS modes “imaging” (broad-band, SHARDS filters, tunable filters),  “spectroscopy” (long-slit, MOS), and “frame transfer and fast photometry” are offered. Multi-Object Spectroscopy (MOS) observations will be part of the observing queue only if the proposals are ranked in the top half (first and second quartiles) of the Spanish CAT final list. However, any proposal in the third and fourth quartiles that has the MOS masks already fabricated from previous semesters will be also included in the observing queue. Applicants must indicate whether their MOS masks are to be fabricated or are available from previous semesters.
  • CIRCE “imaging” and “fast photometry” modes are offered. 
  • Visitor programs are welcome, but will only be admitted whenever they fall in the top half of the ranked proposal list. The applicants must clearly indicate they are applying for visitor mode. A backup program (in visitor mode) should be defined in the case the observing conditions for the main program are not met.
  • Target-of-opportunity proposals are accepted.
  • Approved CAT proposals ranked in the first quartile, will be granted an extended life-time of three semesters, or until their completion, whichever comes first. Note that all phase II information must be submitted to the GTC at the deadline corresponding to the semester in which the proposal is accepted.

FILLER PROPOSALS: In order to have an efficient queue-scheduled observations scheme for the GTC, it is useful to have a set of “filler” programs that can be executed under adverse observing conditions (bad seeing, poor sky transmission, etc.) and with targets spanning a wide range in right ascension (RA). Proposers may request filler status for their program, and during the proposal selection process CAT will evaluate their suitability for this category. Such proposals can request a large number of observing hours. In order to be considered as filler proposals they must fulfil the following requirements:

  • Their observing requirements should be very relaxed, i.e. little or no restrictions on seeing or cloud coverage. 
  • The chosen observing mode should be a frequently used mode, specifically broad/narrow-band imaging and long-slit spectroscopy for OSIRIS, and broad-band imaging for CIRCE.
  • There is a scientific gain even if only a small fraction of the requested observations are executed.
  • A list of targets with a broad RA coverage is provided or,  if only few targets are included, they must have good visibility during the semester.

Note that filler proposals have generally been highly successful in the last semesters.

SPANISH/MEX TIME: Up to 2.5% of the GTC observing time is reserved for collaborative proposals between Spanish and Mexican astronomers. To send proposals under this agreement, select the Special Agreement“Spanish/Mex Time 2017A” in the CAT application tool

WHT, INT (ING proposals)

Detailed information provided by the ING Observatory can be found in the ING call for proposalsAll potential applicants must become familiar with the series of changes in instrument availability and of observing time at the WHT and INT driven by the arrival of new survey instruments. The changes are summarized here

The main changes for 2017A are:

  • AF2 will be offered.
  • INTEGRAL will not be available, and the WHT’s PF imager is no longer offered.
  • See the complete list of offered instruments here
    • INT: IDS, WFC.
  • Large program proposals requiring WHT and INT observing time over two semesters (2017A and 2017B) can be submitted. Any instrument, except for AF2, can be requested in this category. The number of nights available for large programs on the WHT and INT are indicated below.
  • Applicants are encouraged to submit proposals for large time allocations, even within one semester.
  • At the INT, service observations of approved CAT programs are offered through collaboration with the INT student support astronomers. Details are provided in page 3 of the ING call for proposals.

Investigators wishing to submit proposals to use an established WHT visitor instrument (GHaFaS, PAUCam, PN.S) should follow the instructions given in the ING call for proposals.

About 35% of the observing time at the WHT is managed by CAT. Starting from semester 2013B, 20% of the time is distributed to the best-ranked proposals from the Spanish community, and the remaining 15% will be reserved for proposals led by PIs affiliated to the IAC.


Offered instruments are available here. In semester 2017A, GIANO is offered on a shared-risk, best effort basis: it has a new configuration with an optical relay instead of a fibre connection, improving throughput and radial velocity precision. 

Starting in 2017A, TNG semesters are shifted with respect to previous calls for proposals (see Table above). Applicants should pay attention to time constraints and preferred periods when preparing their proposals.

Regarding Large Programs requiring TNG, see below.

Other telescopes

Offered instruments in 2017A can be found on the following web sites:
Check the restrictions and guidance notes for the Liverpool Telescope.
Regarding Large Programs requiring NOT, Mercator, Liverpool or Stella, see below.


Large programs are expected to accommodate projects that require long-term or synoptic coverage, and large-size projects. They must  satisfy these four requirements: 

  • involve novel ideas, opportunities for great advance, or legacy programs, 
  • span between two and four semesters, 
  • publicly release their final high-level products in an appropriate format, and 
  • be led by a Spanish institution (a large fraction of the team should be affiliated to a Spanish institution).

Considering the time allocated to on-going large-programs, in 2017A the following time is available for Large Programs:

  • TNG: 6 nights in 2017A, 10 nights in 2017B and subsequent semesters. 
  • WHT: 8 nights in 2017A and 8 nights in 2017B (only two semesters).
  • INT: 11 nights in 2017A and 26 nights in 2017B (only two semesters).
  • NOT: 10 nights per semester.
  • Mercator: 15 nights per semester.
  • Liverpool: 20 h in 2017A, 50 h in 2017B, and 100 h in 2018A and 2018B.
  • Stellar-SES and Stella-WiFSIP: 100 h per robotic telescope and per semester.

All large programs will be evaluated by the CAT and advised by external expert referees, based on the above criteria. Yearly progress reports are expected, and a final report to the CAT is due at the end of the project.  Raw data from long-term programs will follow the same proprietary period as regular proposals. Up to 66% of the time distributed by the CAT on the Liverpool (LT), Mercator, STELLA, and INT, up to 33% of the time on NOT and TNG, and up to 15% of the time on the WHT may be assigned to large programs.

How to submit

Applicants must ensure that their proposals comply with the required page limits and layout indicated below. The use of English is recommended. Large program proposals must be written in English. To send proposals, use the night time CAT application tool at  A simple manual to learn how to deal with this application is available in this pdf document. To submit a proposal, the PI and co-Is need to be registered. If you are already registered but you do not remember your password, please do NOT register twice (in order to avoid confusions for statistical purposes). You can find instructions about how to reset your password in the same webpage.

Remember to use the latest LaTeX style, which is available at The form is also available in Word format at Please note that applications forms are different for LARGE (long-term) and REGULAR programs. Note also that the time request in the on-line application tool has changed, as one should now specify the  time requested for each semester by creating as many “Observations” as needed.

In the evaluation of proposals, CAT will take into account the publications derived from previous observations with the CAT telescopes. Therefore, in the BIBCodes menu of the application tool, remember to update the fields Comment and Bibliographic code  for all proposals approved in the last two years.

Before the deadline expires, please check that the uploaded pdf file contain the latest version of your proposal, and that it prints correctly. No replacement or updating of the proposal content will be made after the deadline, and those proposals which do not correctly print out or lack relevant sections will be automatically withdrawn from the evaluation process. Those proposals where the font size (10pt) has been reduced or the text of the scientific justification exceeds limitations (one page for common/regular proposals and two pages for large programmes) will also be withdrawn. Figures and Tables cited in the scientific justification should fit a maximum of one page (normal proposals) and two pages (large programs). It is advised to follow the instructions described at


UPDATED on 6 Sep 2016.

Contact e-mail: catiac at