CFHT Call for Proposals


The 2021A CFHT call for proposals is now closed.
The 2021B Call for Proposals will open around Feb 18 2021.

CFHT adapted the Northstar Phase 1 tool written initially for the Radionet community. Northstar has been ported to CFHT and modified in house to handle our specific requirements. You can access the CFHT Phase 1 tool here during the call for proposals period or if you are interested in submitting a Director Discretionary time proposal.

Information on 2021A (for reference only)      [1 Feb 2021 - 31 Jul 2021]
New tutorial on the SITELLE ETC.
SPIRou notes.
Double-blind peer review of proposals
Estimated time allocations.
Approximate RA pressure from Large Programs.
Approximate availibility of bright and dark time.
Large Programs Completion Policy.
Delay in reporting observation's metadata.
SNR-QSO mode.
ETC values into PH1 proposal.
Snapshot programs.
WIRCam staring mode.
More details on Large Programs.

New tutorial on the SITELLE ETC.

A new tutorial on the usage of the SITELLE ETC is now available on the instrument's ETC webpage.

SPIRou notes.

  • The QSO Team may have to skip one or more PI transits, regardless of the grade and rank of the program(s), to avoid scheduling PI transits on consecutive nights. See SAC recommendation #3 of the May 2020 meeting for more details.
  • Some targets are reserved for the SPIRou Legacy Survey and cannot be accessed by other programs with the same science as the SLS. The list of the SLS targets can be found here. Please make sure that your proposal does not include those targets. Duplicate targets with the SLS will not be available for observing.

  • The overheads of the instrument are now 28s per exposure in spectral mode and 35s per exposure for polar sequences. Please see the QSO page for more details.

  • If your targets can either be observed with SPIRou or ESPaDOnS, please make sure you make a note of it in your Technical Justification.

Double-blind peer review of proposals.

For Canadian proposals, any information that leads to the knowledge of the name of the investigators will be withheld from the proposals sent to the Canadian TAC in order to avoid gender and other possible biases. We ask that Canadian applicants make every effort to ensure that their proposals are prepared in a way that does not give away their identity. The Space Telescope Science Institute has posted guidelines for HST proposals. We encourage PIs from all agencies to follow those.

Estimated time allocations.

The 2021A share of observing time is not firmly established yet. This allocation assumes that the associate partners, China and Taiwan, use all their available nights.

  • Canada: A minimum of 25 nights (outside the Large Programs)
  • France and Opticon:
    • A minimum of 17 nights (outside the Large Programs) for the CNRS PIs.
    • CNRS allocated 4 nights to the Opticon ORP program through the OPTICON proposal system.
  • University of Hawaii: A minimum of 22 nights (outside the Large Programs).
  • ASIAA: Up to 5 nights.
  • NAOC: Up to 15 nights.

Approximate RA pressure from Large Programs.

During the 2021A semester, the Large Programs will be using the RA ranges in the table below:


Approximate availibility of bright and dark nights for PI programs.

During the 2021A semester, PI programs have access to a total of 88 nights, 47 with the Moon illumination less or equal to 50% (Dark time), and 41 nights when the Moon illumination is greater than 50% (Bright time). The dark time is split between MegaCam and SITELLE and the bright time between ESPaDOnS, WIRCam and SPIRou. The 47 nights of dark time available to PIs corresponds to approximately 282h of validated time and the 41 nights of bright time correspond to approximatively 266h of validated time.

The r-band portion of the CFIS Large Program requests IQ<0.8" and grey skies, whereas the u-band portion required dark skies and an IQ<1" as measured in the r band. The VESTIGE Large Program requests IQ<1.0" and grey skies. PI programs targeting similar RA and at the same time requesting similar sky conditions will get into conflict with the Large Programs, decreasing the chance of getting observed.

Large Programs Completion Policy

The CFHT Board of Directors adopted a recommendation from the SAC about the completion of the Large Programs. The detailed policy can be found here.

Delays in reporting your observation's metadata.

In Recommendation 4 of the November 2017 meeting, SAC recommended that PIs have the option of requesting a delay in the reporting of the metadata with appropriate justification in their proposals. This can be done via Northstar by checking Yes to the Exception to the Community/World proprietary periods and metadata release in the Observing request tab and writing your justification in the box that appears. The metadata includes the name and coordinates of the targets. Unless the release date for the metadata is extended, they will become available immediately at CFHT and CADC.

SNR-QSO mode.

SNR-QSO is now the default mode for MegaCam and ESPaDOnS and PIs who want to opt-out of this mode must justify it in their proposal. SAC recommendation #6 of the May 2016 report states: SNR-QSO should become the default mode for MegaCam and ESPaDOnS starting 2017A. Program requesting classical mode should justify their request.

For more information about the SNR-QSO mode, please see the SNR-QSO web page.

Other references to the SNR-QSO mode:
  • SPIE 2016 paper, Devost et al.
  • SF2A paper on Espadons by Moutou et al., section 2 covers SNR-QSO
  • ADASS 2013 paper, Cuillandre et al.
  • ETC values into PH1 proposal.

    The PH1 system has been changed to have users include the values of the exposure time calculators into their proposals. Proposals cannot be submitted if this field is not filled. This is not counted toward the page charge. Please include at least a representative set of ETC calculations with your proposal.

    Snapshot programs.

    All agencies are invited to encourage their community to submit snapshot programs. These programs must be able to accept an Image Quality worse than 1.2" or significant levels of extinction. Snapshot programs are used not only during bad weather conditions but also to fill gaps in the queues when no A, B or C program are available or suitable. Snapshot programs are not counted toward an agency's allocation.

    WIRCam staring mode.

    For investigators interested in using the staring mode with WIRCam, please be advised that systematics may be present that limit the achievable accuracy using differential photometry. RMS values <= 0.1% are possible but reaching 0.01% is challenging. See Croll et al (2015) and Martioli et al (2017) for details. Also, experiments switching back and forth between two filters should be considered risky.

    More details on Large Programs.

    Starting in 2020A, CFHT will be executing four Large Programs; CFIS, VESTIGE, SIGNALS and the SLS. These programs are part ot the 2018B-2022A Large programs.

    CFHT will flag any proposal which has conflicts in RA and observing conditions with an existing LP. For information about the relative priority of PI programs and Large programs, please see the recommendation from the SAC (Nov. 2009).

    Information on previous semesters
    If you wonder about the pressure on telescope time, the relative requests on the main instruments, you can have a look at some graphs for past rounds of proposals here.


    Good luck and clear skies!